Author: Joseph LeDoux

Topics: Neuroscience, Evolution, Anthropology

All information is attributed to the author. Except in the case where we may have misunderstood a concept and summarized incorrectly. These notes are only for reference and we always suggest reading from the original source (this book contains amazing diagrams).

Contents

Prologue: Why on Earth?

Part 1: Our Place in Nature

Chapter 1: Deep Roots

Chapter 2: The Tree of Life

Chapter 3: Kingdoms Come

Chapter 4: Common Ancestry

Chapter 5: It’s a Livin’ Thing

Part 2: Survival and Behavior

Chapter 6: The Behavior of Organisms

Chapter 7: Beyond Animal Behavior

Chapter 8: The Earliest Survivors

Chapter 9: Survival Strategies and Tactics

Chapter 10: Rethinking Behavior

Part 3: Microbial Life

Chapter 11: In the Beginning

Chapter 12: Life Itself

Chapter 13: Survival Machines

Chapter 14: The Arrival of Organelles

Chapter 15: The Marriage of LUCA’s Children

Chapter 16: Breathing New Life into Old

Part 4: The Transition to Complexity

Chapter 17: Size Matters

Chapter 18: The Sexual Revolution

Chapter 19: Mitochondrial Eve, Jesse James, and the Origin of Sex

Chapter 20: Colonial Times

Chapter 21: The Selection Two-Step

Chapter 22: Flagellating Through the Bottleneck

Part 5: … And Then Animals Invented Neurons

Chapter 23: What Is an Animal?

Chapter 24: A Humble Beginning

Chapter 25: Animals Take Shape

Chapter 26: The Magic of Neurons

Chapter 27: How Neurons and Nervous Systems Happened

Part 6: Metazoan Bread Crumbs in the Ocean

Chapter 28: Facing Forward

Chapter 29: Tissue Issues

Chapter 30: Oral or Anal?

Chapter 31: Deep-Sea Deuterostomes Link Us to Our Past

Chapter 32: A Tale of Two Chords

Part 7: The Vertebrates Arrive

Chapter 33: Bauplan Vertebrata

Chapter 34: The Life Aquatic

Chapter 35: On the Surface

Chapter 36: The Milk Trail

Part 8: Ladders and Trees in the Vertebrate Brain

Chapter 37: Neuro-Bauplan Vertebrata

Chapter 38: Ludwig’s Ladder

Chapter 39: The Triune Temptress

Chapter 40: Darwin’s Muddled Emotional Psychology

Chapter 41: How Basic Are Basic Emotions?

Part 9: The Beginning of Cognition

Chapter 42: Cogitation

Chapter 43: Finding Cognition in the Behaviorist Bailiwick

Chapter 44: The Evolution of Behavioral Flexibility

Part 10: Surviving (and Thriving) by Thinking

Chapter 45: Deliberation

Chapter 46: The Engine of Deliberative Cognition

Chapter 47: Schmoozing

Part 11: Cognitive Hardware

Chapter 48: Perception and Memory Share Circuitry

Chapter 49: The Cognitive Coalition

Chapter 50: Rewired and Running Hot

Part 12: Subjectivity

Chapter 51: Being There

Chapter 52: What Is It Like to Be Conscious?

Chapter 53: I Want to Take You Higher

Chapter 54: Higher Awareness in the Brain

Part 13: Consciousness Through the Looking Glass of Memory

Chapter 55: The Invention of Experience

Chapter 56: Ah, Memory

Chapter 57: Putting Memories in Their Place

Chapter 58: Higher-Order Awareness Through the Lens of Memory

Part 14: The Shallows

Chapter 59: The Tricky Problem of Other Minds

Chapter 60: Creeping Up on Consciousness

Chapter 61: Kinds of Minds

Part 15: Emotional Subjectivity

Chapter 62: The Slippery Slopes of Emotional Semantics

Chapter 63: Can Survival Circuits Save the Day?

Chapter 64: Thoughtful Feelings

Chapter 65: Emotional Brains Run HOT

Chapter 66: Survival Is Deep, but Our Emotions Are Shallow

Epilogue: Can We Survive Our Self-Conscious Selves?

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Prologue: Why on Earth?

Seth Grant found parallels in plasticity-related genes between rodents and sea slugs. Then realized that some of the same genes even exist in single-cell protozoa. Animals and protozoa share a common ancestor that lived over a billion years ago. The logical conclusion is that behavior, learning, and memory don’t actually require a nervous system.

When animals engage in defensive, energy management, fluid balance, and reproductive behaviors by freezing/fleeing, eating, drinking, and mating, we often describe these activities as an expression of underlying psychological states – fear, hunger, thirst, and sexual pleasure. Because humans consciously experience feelings when we engage in our survival behaviors, we intuit that these feelings and their respective behaviors must be related, with feelings as the cause. In reality, the behaviors and feelings occur simultaneously because their respective systems are responsive to the same stimuli.

Part 1: Our Place in Nature

Chapter 1: Deep Roots

Books to follow up on:

• • • From Bacteria to Bach and Back by Daniel Dennett
    • The Strange Order of Things: Life, Feeling, and the Making of Cultures by António R. Damásio
    • The First Minds: Caterpillars, ‘Karyotes, and Consciousness by Arthur Reber

The core survival requirements were solved by the first successful living organism billions of years ago, and that passed on to every organism that followed. Behavior is not a tool of the mind. First and foremost it is a tool of survival.

We need to be clearer about which aspects of human behavior are related to processes inherited from various other organisms, so that we can better understand those that are not.

Chapter 2: The Tree of Life

Human “exceptionalism” is for many people an unquestioned assumption. For the religious, it is a god given fact. For humanists, it is a celebration of our special powers of thought and feeling. If by special we mean different, then sure. However, this assumption has led to many “social truths” being heavily anthropomorphic. As a result, the foundation of certain unquestioned ideas in the current zeitgeist are extremely hard to clear up without disturbing the status quo.

Chapter 3: Kingdoms Come

The invention of the microscope in the seventeenth century led to the discovery of microbes. The six Kingdoms are unicellular – protista, bacteria, archaea and multicellular – fungi, animals, and plants. 

Chapter 4: Common Ancestry

Nick Lane (The Vital Question): the ancestor of life on earth is a cell that arose between 4-3.8 billion years ago, about half a billion years after earth was formed. LUCA – Last universal common ancestor. Not likely to be the first instance of life. RNA, DNA, and proteins likely formed primitive forms called protocells.

Natural selection drives organisms toward a better fit for their environment. If resources change, the organisms that are better adapted to suit the new environment will survive. A group that has done really well in the past may become vulnerable with the introduction of a predator they aren’t adapted to avoid. Besides selection and migration, genetic mutation is also a key source of variability. Genetic drift: random changes in the frequency of certain genes in a population. Like a hurricane wiping out a certain trait in a population with no regard to the actual trait itself. Less numbers, less likely to reproduce.

Differences based on common ancestry are said to be homologous, while those that are not based on common ancestry are merely analogous.

Chapter 5: It’s a Livin’ Thing

An organism is a living thing, an entity that functions as a physiological unit, the component parts of which operate with a high degree of cooperation and a low degree of conflict to help ensure well-being and sustain the life of the overall entity and to reproduce itself so that its kind can continue.

Its objective is to acquire nutrients and energy so that growth can occur and life can be sustained to at least the point of reproduction. Viability (the ability to grow and persist) and fecundity (the ability to reproduce) are key characteristics of organisms. They both require metabolism. Living things make and use energy in the process of living, while nonliving things are acted on by energy.

Part 2: Survival and Behavior

Chapter 6: The Behavior of Organisms

While an organism’s traits are useful in the quest to survive, their behavior is a decisive factor in natural selection. Behavior is a feature of all organisms, not just those that have nervous systems or muscles. BF Skinner defined it as “that part of the functioning of an organism which is engaged in acting upon or having commerce with the outside world.”

A reflex is the simplest form. An innate stimulus-response reaction that occurs by way of nerves, that directly connect sensory input systems with muscles. Automatically elicited by certain stimuli and are not dependent on volitional control.

Fixed reaction patterns are complex hardwired responses that are similar to reflexes as they may be inborn. Complex sequences of behavior like a mother goose extending the neck when an egg is out of the nest to retrieve it. Universal survival activities like eating and drinking too. Although, species specific. They can be influenced by environmental factors, so not necessarily innate.

Chapter 7: Beyond Animal Behavior

What a Plant Knows – Daniel Chamovitz. Plants follow the sun by bending stems and aligning their leaves to get maximum exposure to light and to promote growth.

Brilliant Green – Stefano Mancuso and Alessandro Viola. Plants possess sight, touch, smell, hearing, and mineral detection, moisture, magnetic signals, and gravitational pull. Even though people don’t like thinking about plants as being alive (no neurons), they breathe, digest, and move (behave). They have intelligence, as long as the definition means the ability to solve problems through behavioral interactions with the environment.

Even protozoa have taxic responses and behavior. Unicellular organisms can change behavior and even learn and remember.

Chapter 8: The Earliest Survivors

By 3.5bya bacteria had emerged. They run or tumble to get around. Motility has both costs and benefits. It requires flagella, and flagella movement is metabolically expensive. On a positive note, it adds leverage in food acquisition and avoiding harm. Their movements are called taxic behaviours – toward useful or away from harmful substances. Chemo and photo receptors. Less tumbling occurs when an attractant is detected. Straight towards the substance. With repellants, tumbling increases, changing direction and withdrawing. Electrolytes and water are also balanced within the cell to prevent excess or deficiency.

When animals have low electrolytes they seek out salt. When they have too much they seek water to clear. Animals also have thermoregulation inside and behavior. Bacteria do this by reconfiguring certain biochemical processes to adjust their physiology and to match their external temperature.

Sex evolved as a modification of cell division in single-cell protists and would not exist without the asexual solution to reproduction that bacteria have used for billions of years. They may not have sex but they can be social. In the case of creating biofilm, they can communicate by generating electrical signals, which they use to coordinate feeding and reproduction and to attract new members.

Bacteria can acquire information about the world and use it to change future behavior. They form internal molecular representations of environmental conditions (temp, O2 levels) and use them to predict environmental conditions later.

Chapter 9: Survival Strategies and Tactics

Approach and withdrawal may be universal simply because they are subject to the laws of physics, not because they reflect psychological motivations (polarity, temperature, entropy, etc?). The evolution of nervous systems in animals provided novel options for approach and withdrawal beyond simple taxic responses. They can be implemented in a more precise way and the added complexity resulted in behavioural quirks. We withdraw from danger and are attracted to sexual desire and food. Emotional states should not be called upon to explain behavior. They are mediated by different brain circuits.

Chapter 10: Rethinking Behavior

Our everyday vernacular arose and still persists because it enables discourse about the inner lives of people as they interact with one another. Great for survival, but not so much for scientific discourse. We easily convince ourselves of the connection between behavior and mental states. Over time, the more subtle distinctions are lost and we end up thinking that names/terms are literal. Folk psychology often serves as a starting point for scientific inquiry into the mind and behavior. Because it is entwined into our vernacular language regarding the mind, our mental-state words provide labels for meaningful categories of experience. Behavior did not emerge to serve the subjective mind. It came about to enhance fitness-to keep organisms alive so reproduction can occur.

Part 3: Microbial Life

Chapter 11: In the Beginning

Big bang (13.7bya)->First galaxies (10bya)->Solar system (4.6bya)->Molten earth (4.5bya)->Earth cools (4.2bya)->Life (~3.8bya)

Water provided a medium for chemical compounds to dissolve and be reconfigured as other compounds. Water + heat + carbon. The compounds carbon create are highly stable and don’t readily come apart in water unless the temperature goes up to facilitate breakdown. Sunlight, volcanoes, underground magma, and lightning can fulfil that requirement. Through regular chemistry, atoms can be combined to make complex carbon-based molecules. With just carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur you can create carbon-based molecules that play crucial roles in cells. Proteins, lipids, and carbs.

Proteins are the foundation of cell function, act as receptors that detect useful chemicals or transport chemicals in and out of the cell, or as enzymes that regulate chemical reactions, such as those underlying metabolism. They also contribute to forming an internal scaffold that gives a cell shape.

Carbohydrates also contribute to cell structure but are more important for energy metabolism and energy storage.

Lipids form the casing or membrane that surrounds the cell and separates it from the outer world, and also store energy and insulation.

Replicative chemistry also involves these interactions. Nucleic acids, DNA and RNA, can self replicate.

Chapter 12: Life Itself

Gerald Joyce believes RNA was developed first, which jump-started evolution, but needed to create DNA to support a large genome.

Self-replicating RNA and DNA molecules, according to this model, were initially free-floating, but were later compartmentalized. Allowing protein products of DNA and RNA to be confined and used by the structures inside. Perhaps first in the pores of a rock, not sustainable, until a lipid structure was created. This allowed them to move, replicate, and evolve. Possibly these early cells would collect resources, which would facilitate reaching a threshold where the whole cell would divide due to a limit within the lipid casing. Might be polarity or pressure.

Alternatively, RNA/DNA could appear after biological entities could support metabolism. Günter Wächtershäuser proposed a version of this metabolism-first theory in which hot water from volcanoes flowed over mineral-rich rocks to ignite (catalyze) chemical reactions that fused simple carbon-based compounds into larger ones. The reforming of materials could have formed a basic protocell. This was met with critique saying the volcano vents would be too hot for life, but Mike Russell and Bill Martin solved this problem with the alkaline hydrothermal vent theory. It is widely accepted that the early oceans were cold and acidic due to abundance of positively charged chemicals. The water would go through cracks to the mantle, get heated, and flow over carbonate and pyrite vents making it more alkaline – creating a negative charge. This alkaline fluid would get trapped in the vents, separated from the acidic ocean by a foam barrier consisting of iron sulfide. Hydrogen and carbon dioxide could construct formaldehyde or acetate with iron sulfide as a catalyst. Once it could leave the pore as a lipid encased protocell it could self-replicate.

Either theory could be the case, or in tandem. Regardless, they both provide reasoning behind the importance of a negative charge inside cells and lipid membranes.

Chapter 13: Survival Machines

Life as we know it began about 3.8billion years ago. By 3.5bya, LUCA’s descendants had diverged to form bacteria. Archaea then branched off. One reason for their longevity is they are able to live under many different climatic conditions. They survive on land, air, and water. Bacteria thrive in moist, warm recesses of our body, but also snow and ice, and in deep-sea vents. Some archaea can survive up to 200degrees Fahrenheit, in waters of high salt concentration, and even acid.

The survival and wellbeing of any cell depends on the active exchange of molecules between the outside world and the cytoplasm, by passage of the cell membrane. The membrane is selective and this discretionary permeability is dependent on the molecular composition of the membrane.

Once inside the cytoplasm, externally acquired ingredients contribute to the complex chemical reactions that make enzymes and other proteins used in energy generation, maintenance of fluid and ion balance, regulation of inner temperature, and control of cell movements in acquiring nutrients and defending against harm. Metabolism generates waste that must be excreted through the cell membrane, often with the help of transporters.

Bacteria and archaea have a cell wall as well as membrane to protect them. The wall allows more chemicals through, except large toxins, to move freely through. Its rigid shape prevents the cell from collapsing when water leaves, and from exploding when it enters.

The cell membrane maintains the balance of charge between inside and out. This chemical balance (acid out, alkaline in) is essential for sustaining the inner workings of metabolism.

Tyler Volks point out that cells are self-generated dynamic entities that at any given moment are always on the cusp between persisting and perishing. They manage to survive by using metabolism to stay ahead of the game. When metabolic waste is expelled, the result is a loss of molecules. To compensate, cells also use metabolism to grow new molecules. If the exchange is at least equal, the cell can persist in its present form. More molecules = growth and protection against perishing. But a cell can only grow so much, as a larger cell requires more nutrients, and the cell runs up against a basic principle of physics. As a sphere gets bigger, its interior increases to a greater degree than its surface area. This makes it harder for the surface to keep the flow of nutrients enough to sustain the ever-larger interior. So, it divides and starts again. Mitosis. Vertical gene transfer involves passing genes from parent to offspring. Horizontal gene transfer takes genes from other organisms. Genetic mutations also contribute to variability.

Using antibiotics to destroy the membrane of a bacteria can only work as long as they aren’t using horizontal gene transfer and undergoing mutations.

Chapter 14: The Arrival of Organelles

2bya Eukarya appeared. In bacteria and archaea, DNA floats freely within. Eukaryotes, it is isolated from the rest of the cytoplasm. Eukarya = true kernel. Nucleus is surrounded by a nuclear membrane. Membrane enclosed structures inside are called organelles. One of these organelles is mitochondria. Dedicated energy machines that are more efficient than the energy producing capacities available to prokaryotes.

The endoplasmic reticulum and golgi apparatus are involved in the manufacture and regulation of proteins made under instructions from the DNA in the nucleus.

Because Eukaryotes don’t have a rigid cell wall they require a system of filaments, made of proteins, that form an inner scaffold called the cytoskeleton. Prokaryotes have a cytoskeleton but it is less elaborate, as it doesn’t need to form the cell shape. The EK uses it as a chemical transport system that facilitates communication between the different parts of the cell. They are large so need the communication. They also needed other changes that are related to metabolism to support their larger cell volume. Which is the role mitochondria play.

Chapter 15: The Marriage of LUCA’s Children

It is believed the change occurred with in-folding the cell membrane in archaeal cells to create a nucleus. Making the nucleus the control center, DNA instructing RNA to undergo protein synthesis. Also, the archaeal cell engulfed a bacteria without the bacteria being digested. The long term relationship became mutually beneficial – or symbiotic. This became the Last Eukaryotic Common Ancestor (LECA).

Nick Lane suggests that prior to this, Archaeal cells lived on gases – hydrogen and C02. Once it had the bacteria, it was able to utilize the energy produced. The endosymbiotic theory (Lynn Margulis).

Chapter 16: Breathing New Life into Old

Animals obtain energy from carbon containing compounds by consuming and digesting other organisms (animals, plants, fungi). Fungi get energy by releasing digestive chemicals externally, then consuming. The end result being glucose, which is delivered to cells for mitochondria to use oxygen to break down into energy. Cellular respiration.

Plants mainly make energy using chloroplasts, which capture sunlight, in a process called photosynthesis. Water is absorbed from the roots and CO2 extracted by leaves are broken down to yield glucose, which is stored as starch and used as fuel. Plants also have mitochondria to make energy in darkness.

The by-product of photosynthesis is oxygen. When photosynthetic organisms multiplied rapidly, the atmosphere contained sufficient oxygen to foster a growth spurt of O2 dependent organisms. Tyler Volk calculated that the recycling of CO2 between O2-breathing and photosynthetic organisms increased global photosynthesis by 200-fold vs when it was supplied by volcanoes and rock weathering. Protista also fall under the multicellular category.

Part 4: The Transition to Complexity

Chapter 17: Size Matters

EK’s ability to increase in size created the first true predators and prey. Lane suggests there is a limit on energy produced per gene and that EK can generate 200,000x more per gene than PK (Energy demand vs cell size limit). Preventing them from growing. Mitochondria to the rescue y’all. The first major bump in O2 occurred 2bya, before the arrival of EK. Thought to have resulted, in part from Photosynthetic PK. The second rise was 800mya. Making it possible for even larger, energy demanding multicellular organisms (animals, plants, and fungi) and contributed to diversification. Mitochondria solved the energy problem, the cytoskeleton solved the structure problem, and the transporter proteins the carriage problem.

Most animal phyla have only been around 500my and distinct animal species tend to only last 1-4 my before becoming extinct. So, PK wins out. PK diversified biochemically, enabling them to adapt to environmental changes without having to change structurally.

Chapter 18: The Sexual Revolution

Sex began with unicellular protists – the entire organism essentially a free-roaming sperm or egg cell. Genetic markers of sexual reproduction indicate that the genetic capacity for sex is universal in EK. Some that don’t have sex now may have the lost the ability over time. There are energetic costs to sexual reproduction.

When the sperm and egg meet up, they physically fuse so that the sperm can fertilize the egg. Genes are mixed via recombination. New cells divide and replicate and get differentiated with chemical signals to make skin, muscle, organs, etc (somatic cells).

Horizontal gene transfer can occur in EK. GMO issues are based on the concern that genes from food may be transferred to us and alter our genome.

Asexual reproduction is continuous and fast compared to sexual reproduction. Sex is also inefficient – producing many gametes that get wasted and the recombination process. The advantages are genetic variability during environmental changes. The population as a whole can adapt. As humans we tend to attribute sexual motivation as a psychologically stimulating event when it is not necessarily so in other organisms.

Chapter 19: Mitochondrial Eve, Jesse James, and the Origin of Sex

Most DNA is contained in the nucleus, some is in the mitochondria. In sexual reproduction the nuclear genes are mixed but the mitochondria DNA is passed mainly from one parent (usually mother). Creating the Mitochondrial Eve Hypothesis.

A negative aspect of taking in bacteria, or mitochondria, is the extra free radical release. The fact that transmission is limited to just the female parent may reduce the free radical damage, eliminating physiological conflict, making it easier for two genomes to exist. Sperm are more behaviorally active than eggs and produce more free radicals, potentially damaging mitochondria over time.

Chapter 20: Colonial Times

Colonies are not true multicellular organisms, as their cells are not officially components of a single unitary body. But a certain type of colony launched multicellularity. They adhere to one another and use chemical secretions to stay attached (adhesion molecules) and to communicate with one another (signaling molecules).

Kelp and seaweed are examples of EK colonies. Slime molds (amoeba) have the ability to move across the landscape using highly efficient routes. Colonies form because group existence offers advantages over unicellular life. Safety in numbers, moving as a unit, protection against predators. Survival chores can also be divvied up and specialized. Suppressing the expression of genes that aren’t needed saves energy.

Defectors are a problem in colonies. Moochers take what they need and give nothing back and migration means the new colony needs to express genes to protect themselves again.

Cells in different tissues depend on each other and can’t survive without the cooperation. Survival of the individual cell becomes subsidiary to survival of the overall organism, and mandatory cooperation results. Colonies are the transitional step between unicellular and multicellular organisms. Clonal colonies eliminated defection compared to aggregating colonies with different parents. Karl Niklas believes the jump to clonal colonies was created plants, fungi, and animals.

Chapter 21: The Selection Two-Step

Two key requirements for multicellular life are cell to cell adhesion and cell to cell communication. The reason unicellular colonies can’t achieve this status is because of the lack of sustained cooperative relationship between individual cells. According to Niklas, two evolutionary steps are required to progress to a multicellular organism. First, an alignment of fitness phase has to occur in which genetic similarity among cells prevents conflict between them, thus enhancing cooperation. A unicellular bottleneck. It starts as a single cell and all others are generated from it (zygote). The export of fitness stage, fitness must become interdependent with minimal physiological conflict. Fitness is transferred from the individual to the organism as a whole. Functions are programmed in the genome. Defection cannot occur and it all hinges on sex and the way the egg is fertilized to make diverse genes from both parents.

To survive as a multicellular organism, the individual cells must give up their sovereignty and reproducibility (similar to human civilization except the offspring are given up as a tribute to the system at a deficit). Organisms with harmful genetic mutations tend to die before reproducing and genes are shuffled to lessening impacts from harmful ones.

Autoimmunity has some strong contrasts with a society that has given too much power to those who eliminate defectors. Self-destructive tendencies and false positives.

Chapter 22: Flagellating Through the Bottleneck

The leading explanation for animals is the Colonial Flagellating Hypothesis. Ernst Haeckel. Plants, fungi, and animals each have a protist ancestor. The protist ancestor of animals is an ancient extinct protozoan that is also believed to be the ancestor of protozoa called choanoflagellates.

Flagella movements, called beats, involve wavelike undulations. Cilia rotate rather than undulate. Choanoflagellates are predators, feeding off bacteria. They can control the motion of their movements towards nutrients or away from threats with flagellum by generating electrical signals that cause beating movements. They feed by creating water currents, pulling bacteria toward them and trapping within their collar made of membranes. Then absorbed into the cell.

Asexual reproduction is the norm but they also sexually do under certain conditions. When food supply is limited, cell survival is challenged, and asexually produced offspring that are smaller or larger than normal are produced. They become gametes. Small are sperm and large are eggs. When they fuse they can create genetically diverse offspring.

Cell to cell adhesion happens in colonies and communication is possible. The simplest choanoflagellate colony consists of individual cells forming a sphere, with flagella facing outwards. When cell bodies release chemicals inside, the flagella move in a coordinated beating fashion. Nutrients are then transported across adhesion bridges. One issue is cells can’t feed and divide at the same time. Since they are predators, they need to actively keep feeding. Cell specialization fixed this. Female gametes move to the center of the cell under bad conditions and sperm fertilize. They almost become multicellular but they don’t end up being interdependent.

Ancestral choanoflagellates used electrical signaling to move, like muscle contraction. Also to communicate to other cells like neurons. They also have the genes that animals use to form neurons. Sponges are believed to be the first animals but were unable to build a nervous system (didn’t need one).

Part 5: … And Then Animals Invented Neurons

Chapter 23: What Is an Animal?

Animals differ by consuming other organisms and are motile. Creating predator prey driven evolution. They also developed nervous systems and muscles, which greatly extended their behavioral options. 

Sponges are thought to be the first animals. Fossil records for them aren’t great though, since they have soft bodies that don’t fossilized well. They belong to parazoa with placazoa (also tissueless). Trichoplax is the only known placazoan left. All animals with tissues that form organs and systems belong to a metazoan subsystem called Eumetazoa. Two early ones were Ctenophora (comb jellies) and Cnidaria (hydra, jellyfish, sea anemone, and corals)

Today, more than 99% of animals are bilaterally symmetrical. Most are descended from the same flatworm ancestor (acoel 540mya). Last common bilateral ancestor (LCBA). The Cambrian Explosion between 540my-480mya expanded bilateral species. All sea dwelling.

Chapter 24: A Humble Beginning

The sponge has a choanocyte, similar to unicellular choanoflagellates (flagellum and collars). They line the outside and pinacocytes protect the body but are not tightly connected like our skin. Some sponges develop a shell made of calcium carbonate. The space between the outer surface and inner cavity is called the mesophyll, and contains an endoskeleton made of spongin. The endoskeleton in some sponges also has mineralized particles of calcium carbonate that add support. Since they are stationary, they release noxious chemicals into their surroundings, and with external calcified barbs to deter consumption. They also expel sediment and waste by inflating and collapsing to force it out. Controlled by myocytes. Thought of as precursors to muscles but without nerves.

Chapter 25: Animals Take Shape

Choanocytes capture and amoebocytes absorb and transport. Eumetazoan animals that followed had cells that formed digestive tissues, organs, and systems. The cnidarian descendants of sponges had a specialized mouth organ connected to a digestive system. Cavlier-Smith argues sponges are the only animal to evolve multicellularity without changing the absorptive feeding. Some must have evolved a new body plan for feeding. Specialized cells that formed appendages with sharp barbs that could catch and transfer food, through the mouth and into a specialized internal digestive organ – a gut, which formed by sealing the body pores.

Jellyfish use tentacles to search for food. They are home to cnidocyte cells. When contact is made, they activate, but only if the chemistry of the object is indicative of prey. A barb unfolds and attaches, injects toxins to immobilize, then delivers it to the mouth and gut. There, gastrodermal cells release chemicals to digest and make energy. Tentacles are used in sexual reproduction. The male hands the female sperm. They can also engage in hermaphroditic fertilization. Complex movements of tentacles and body require tissues that can rapidly respond to sensory information when engaging in survival activities. Muscle would help to contract faster but can’t activate fast enough with diffusion of chemicals. So, neurons evolved in tandem with muscles.

Chapter 26: The Magic of Neurons

Like all cells, neurons have a cell body, but additional nerve fibers. One is an axon, which extends out of the cell body and enables the cell body to send messages over long distances to other neurons. Dendrites extend out like antennae for short distances and receive messages transmitted from axons of other neurons. It adds an electrical step between the chemical one to transmit signals faster. In its most fundamental sense, a nervous system is a sensory-motor integration device. Inputs come in the form of messages from sensory receptors specific to key stimuli (light, sound, touch, odors, tastes) and the outputs involve motor effectors. The most basic job of a nervous system is to connect sensory receptors with motor effectors.

Chapter 27: How Neurons and Nervous Systems Happened

In a sponge’s youth, they are mobile. The outer body surface of larval sponges has cilia, which is used to move around. Swimming cells have short cilia and cover most areas. They beat constantly, causing random, undirected movements that keep it moving and afloat. Steering cells have long cilia, which are concentrated at one end. Sensitive to light, which causes it to bend, directing movement toward light sources. They probably evolved basic neurons to move quickly and then got rid of them at maturity. By having lots of cells they could divvy up roles. Possibly clustering muscle cells and sensory ones together for efficiency. Next, growing an extension of the sensory body outward. This could work with diffusion until too slow. Needed axons for rapid communication.

 

Sponges apparently have the genes necessary for synaptic vesicles but don’t have the molecular signals to activate them in a coordinated fashion in development. In humans, neurons and skin cells both arise from the ectoderm layer. A more complex neural net led to more complex and specialized behavior. A jellyfish neural net seems to display the early plans of complex bodies and brains.

It has been suggested that the key factor for the Cambrian explosion of animal bodies was the advent of the nervous system-based learning. Nervous systems made learning sophisticated and flexible. Leading to the ability to explore new niches. The evolutionary arms race would have accelerated, creating unprecedented changes to the body. Furthering Bauplan diversification.

Part 6: Metazoan Bread Crumbs in the Ocean

Chapter 28: Facing Forward

650mya animal life was dominated by aquatic organisms with asymmetric or radial bodies that lacked a nervous system, or at best had a simple one (cnidarians and ctenophorans). Then around 630mya, a new body style – bilateral symmetry appeared. They went on to acquire nervous systems that sported a collection of neurons in the head – a brain, which could evaluate the environment and behave in ways more complex than ever. During the Cambrian Explosion 543-480mya, brainy bilaterals were numerous and diverse. By 400mya, some invertebrates had invaded the land (in particular millipedes). 350mya they were joined by amphibians, the first vertebrates to live by breathing atmospheric oxygen.

Instead of having tentacles to grab floating nutrients, like a polyp, or drifting down randomly with the mouth facing down, like medusae, bilateral animals are mobile and have a preferred method of locomotion. Forward is a direction that emerges from the shape of a bilateral body.

Bilaterals were the first to have a head, and the direction that head faces is forward. It is also the location of key sensory organs (eyes, ears, nose) that guide forward moving behaviors in the search for food, drink, shelter, or mates and away from danger. Predator-prey interactions accelerated complexity in bilateral animals, allowing chase and escape.

Chapter 29: Tissue Issues

Eumetazoans, are animals with tissues (radial and bilateral) that are a result from specialized cells. Daughter cells divide, to give rise to identical cells that collect together in a single layer to form a hollow sphere called a blastula. This folds inwards to form the gastrula, with distinct layers of embryonic cells (where specialized cells are made from).

Radials are diploblasts, as they have two embryonic cell layers, while bilaterals are triploblasts, having three. In radials they are the ectoderm and endoderm. The outside covering or skin and the gut. They also have mesoglea, but it is not made of living tissue.

Bilaterals also have a mesoderm – which lies between the ectoderm and endoderm and generates additional cells. A coelom, where the gut and other inner organs reside.

Radials have one opening for the gut and anus. Bilateral eumetazoans have a separate input and output. There is also a nervous system. Cnidarians are basic and lacks or has minimal control over body movements. Some motor coordination but not by the way of central headquarters. This is where newer bilaterals developed a brain to integrate information from sensory organs, such as paired eyes, to movement.

Scientists believe the Last Common Bilateral Ancestor (LCBA) was a primitive worm. It is thought that the LCBA emerged as a modification of the cnidarian larval body, and inherited a diffuse nervous system and an incomplete gut.

Chapter 30: Oral or Anal?

During the early life of bilaterals, the blastula folds inward forming the gastrula, and the fold gives rise to an opening that becomes the digestive tract (protostomes – mouth first). Most invertebrates belong to this group. The rest are anus first (deuterostomes – mouth second). A unique set of invertebrates that are ancestors of vertebrates. By 580mya they had both appeared.

The proto-deutero ancestor (PDA), came after LCBA, which arose about 630mya from radial. The PDA is thought to be Nephrozoa, the clade when coelom appeared. Including proto and deutero – practically all existing animals.

Protostomes are divided into two groups: flatworms, annelids (segmented worms), and mollusks (clams, oysters), and the other arthropods (insects, arachnids, crustaceans) and roundworms. They are defined by whether it grows continuously or sheds its body and starts fresh at some point. Genetic analysis shows mollusks have more in common with deutero than arthropods and roundworms. Suggesting annelids and mollusks offer advantages as model systems for understanding human function and disease, despite worms and fruit flies being more popular in genetic studies.

Chapter 31: Deep-Sea Deuterostomes Link Us to Our Past

Starfish are deutero and are bilateral as larvae, but lose it as they mature. Larval states are more directly related to an organisms history than adult.

Even though we are closer related to urochordates than other groups, the groups have both diverged and their genomes have undergone extensive transformation. Meaning cephalochordates better represent the ancient chordate history and are a better model of vertebrate origins.

Chapter 32: A Tale of Two Chords

Chordates – No other organism has a notochord. A flexible, hollow rod made of cartilage that runs along the axis of the chordate body along its dorsal side, or back. A primitive skeleton that supports the body against the pull of gravity – the skin and some inner body parts hang from it. The gelatinous filling at its hollow center enables its body to be flexible and to engage in undulatory swimming movements. Annelid worms, ancestors of which were early protostomes, possess a longitudinal muscle, called the axochord.

Protostomes and cephalochordate deuterostomes inherited from the PDA a central nervous system consisting a brain and nerve cord, as well as a structural support chord (an axochord in protostomes, and a notochord in chordates). With evolution of vertebrates, the notochord gave way to the spine (vertebral column), and the dorsal nerve cord became the spinal cord.

In embryonic life, all vertebrates possess a dorsal notochord, which is then replaced by a vertebral column as the embryo matures. The gelatinous interior becomes the soft material inside the disks between the vertebrae. When a disk is herniated, the material squeezes out, and with the loss of this cushion, inflammation and compression of nerves can result, leading to sciatica and back pain.

Part 7: The Vertebrates Arrive

Chapter 33: Bauplan Vertebrata

There are approximately 28 bilateral phyla with distinct Bauplan features. 27 are invertebrates, including 23 groups of protostomes and 4 deuterostomes. One vertebrate phylum.

To hunt the ocean waters, while swimming, the capacity for fast, agile swimming, to catch prey and avoid being eaten is required. Having a vertebral structure that can move, provided the flexibility. The vertebral column is attached to the brain, anchors the rest of the skeleton, limbs, muscles, and organs. Just like the notochord did for invertebrate chordates.

An animal’s Bauplan unfolds in early life under the control of its genes. A family of genes called homeobox genes are major players in body construction. These are found in all multicellular organisms. The subset – hox genes, play roles in developing bilateral bodies. Hox genes direct the construction of basic structural features that all protostomes and deuterostomes, all bilaterals, share, such as symmetry along the anterior-posterior axis. They regulate other genes that initiate the construction of specific structures, such as legs and arms, at specific times in embryonic life. Also, organs and size of different body parts. Also nervous systems. Conservation of the Hox genes is what gives all bilaterals their common Bauplan features. The variation in expression of genes between different phyla that contribute to the unique body designs. Protostomes and invertebrate deuterostomes have one cluster of Hox genes, while vertebrates have four sets. This helped them develop complexity.

Chapter 34: The Life Aquatic

530mya a Haikouella preceded fish as the first vertebrate. It was transitional between a notochord and a primitive vertebral column – a notochord with segments.

Fish appeared 520mya during the Cambrian Explosion. The first fish didn’t have bones, but skeletons made of cartilage, making their subgroup cartilaginous fish. They initially lacked jaws. Mouth always open, with stationary primitive teeth as a filter. Active predators that ate while swimming forward (filter forward, filter sand, attach to other animals and sucking out nutrients). Breathed through gills to extract oxygen. Lampreys and hagfish haven’t changed much here.

510mya parts of the gills became a jaw with muscles and teeth.

The largest subset of jawed fish are the ones whose skeletons are made of bones. Appeared around 480mya, more varied diets, with some being carnivores, herbivores, and omni. Early bony fish diverged into animals commonly referred to as ray-finned fish. Bony fish use gills to breathe and fill their swim bladder with air, giving them buoyancy, meaning they can breathe stationary. Sharks must keep moving to keep oxygen over gills. Some sharks can take a break by staying stationary in a moving current of water. The other group is the lobe-finned fish. They split from ray-finned about 440mya and are mostly extinct, but are the kind of fish that subsequent vertebrates evolved from.

Lobe-finned fish have fins made of a single bone surrounded by hunks of muscle tissue. They had two paired sets of these lobes on the ventral side and could use them to walk across the ocean floor and plant their position in currents. This aided their ability to hunt aquatic invertebrates or other fish. The precursor to limbs.

Chapter 35: On the Surface

375mya a Fishapod (Tiktaalik) diverged. A lobe-finned fish equipped with some novel Bauplan accoutrements. Joints added to the stilt-like limbs, enabling smooth walking movements. In addition to gills, they possessed primitive lungs, allowing occupation of warm, shallow water with low O2. The first terrestrial tetrapods.

Amphibians were next and could inhabit both water and land. Frogs are familiar examples that start as tadpoles underwater as vegetarians who use gills, then they develop lungs as a carnivorous adult. However, they couldn’t leave the water without plants getting there first to release O2. Plants got there 50mya earlier as a by-product of photosynthesis.

The first animals to invade land were invertebrate protostomes, like millipedes, which were vegetarian. They lived off mossy growths on rocks. The amphibians would eat them. In response to protostomes eating the plants, they diversified, which was made possible by CO2 exhalation from animal respiration. With more plants to eat, terrestrial protostomes also diversified, in the form of insects and spiders. Amphibians reigned supreme without competition.

As vertebrate life diversified on land, carnivorous dietary options opened up, but so did the chances of being eaten. Amphibians needed to stay close to water to reproduce, but without sexual intercourse. Fish and amphibian eggs are encased in jellylike membranes and are laid in water. Males then release sperm upon them (external sexual reproduction).

By 330mya a new class of tetrapods emerged, amniotes. The fetus develops in an internal, fluid-filled sac and with lungs that extracted oxygen from the air rather than water. Maturing in the female these vertebrates could get away from water. The egg would be laid and hatch on land. This meant external genitalia was required. Genitalia bearing animals make up the remaining vertebrates – reptiles, birds, and mammals.

Reptiles first, their long limbs made them more mobile than amphibians. They split to give rise to birds and mammals. In both birds and mammals, their spatial range of foraging greatly increased, putting additional pressure on the brain to expand to accommodate the challenges involved.

Synapsids were the first group of reptiles to branch off from basal amniotes, about 310mya. These are mammal-like reptiles. They included fierce predators and herbivores. Some were large with fins on their backs and bony armor, others with saber teeth. A second group split off that were small sauropsids. They were no match until about 250mya, the Earth heated, and much of the animal and plant life on land and in the sea perished in a mass extinction.

The most important synapsids that survived were the cynodonts. The size of a large dog and features that showed more hints of mammals we know today (changes in skeletons, jaw, eye socket, ears, hair, and internal body temperature control). The first warm blooded animals. They split into herbivores and carnivores and expanded their territory into a variety of niches and climates. By 210mya they were true mammals.

Surviving sauropsids remained in the background until they spawned dinosaurs about 230mya. The oceans were a hospitable home and they became large sea predators. Eventually some returned to land and became the dominant terrestrial predators. Ancestors of alligators, crocodiles, lizards, snakes, as well as birds. Birds are basically flying reptiles with feathers.

Mammals got wrecked by dinosaurs and had to become nocturnal, surviving on less food and small to avoid them. Tiny shrew-like creatures, living in dense forests.

65mya, 50lb or heavier animals were wiped out. Probably a meteor which produced a cloud of dust which blocked the sun and disrupted photosynthesis. Smaller reptiles, birds, and mammals were impacted less because they needed less to survive. Christine Janis argues it was the small size resulting from not being able to compete that allowed them to survive. “A small animal could be flexible; it could swim, climb, dig, run, or jump as its conditions required. A larger animal had to specialize-and the greater the specialization, the harder it is to alter its body plan to adapt to a changing environment.”

The massive continental drift was around the extinction of dinosaurs, and mammals began to evolve separately and diversify. Further diversification occurred by way of a land bridge between Asia and North America.

Most mammals are of the placental variety (fetus in until breaks, releasing fluid), including rodents, felines, canines, farm animals, flying mammals, marine mammals, and primates.

Chapter 36: The Milk Trail

Reptiles replace teeth, while mammals are born without and replace once. Meaning they need to nurse with mammary glands since they can’t chew. It also meant they could protect the infants in a home area. Some other mammalian traits already existed from cynodonts – legs under instead of to the side to facilitate breathing while running (reptiles can’t). It also made oxygen available for metabolism, and internal heating. The first warm-blooded, or endotherms, able to maintain a core stable body temperature under variations in external temperature. They also probably had fur, which reduced some of the metabolic burden.

Also, converted the 3 chamber reptile heart to 4, they had a powerful O2 delivery system to the tissues to make energy. This internal temperature may have helped them survive the global cooling. Birds independently acquired a warm blooded body. Cynodonts had a double-jointed jaw, out of which hearing capacities developed.

Being nocturnal, early mammals had less need for color vision and developed night vision. Swapping color receptors (cones) for light receptors (rods). Of the mammals, only primates reclaimed complex color vision. Early mammals also developed expanded capacities for smell, facilitated by high oxygen intake though the nose, as well as sound processing enhancements. Reptiles and amphibians mainly hear low frequencies. All because of the jaw converting into a sophisticated eardrum and middle ear bones that helped turn sounds into neural messages to send the brain.

Olfactory and auditory processing systems changed to accommodate the increased importance of these modalities over vision in early mammals, and the visual system had to specialize for night vision.

Primates emerged roughly 70mya. Their diet included leaves, flowers, nuts, and fruits, and had the ability to grasp with hands and feet, enabling tree climbing. To forage and escape predators. Their eyes moved to the front of their face, making binocular vision and depth perception, which are important for leaping and grasping. Moved mostly with two legs, making arms available for swinging, steering and manipulating items.

Early primates were prosimians (lemurs and tarsiers). Two other groups were anthropoids (monkeys and apes) and hominids (humans). Anthropoids emerged to shift to day time feeding because of the fovea (region of the retina with a concentration of cone cells). Daytime was still risky but their high-acuity vision meant they could detect predators easily.

Getting bigger, they reverted to all fours again and needed more energy. Depending on fruit was high energy but unpredictable with competition. These pressures increased brain size, and new brain areas, enhancing cognitive capacities and making possible survival based on intelligence as much as brawn.

Humans 6mya had undergone considerable diversification. They could stand upright but were nothing special. Preyed on by large animals but preyed on smaller ones. Homo had sapiens, ergaster, neanderthalensis, and erectus. 10,000 years ago they were extinct and Homo sapiens were all that was left.

It’s thought that about 70,000-30,000ya genetic mutation allowed a rewiring for for abstract thought and language. Perhaps Neanderthals and sapiens both possessed the ability for symbolic thought and language.

Part 8: Ladders and Trees in the Vertebrate Brain

Chapter 37: Neuro-Bauplan Vertebrata

The canonical vertebrate nervous system consists of a central and peripheral nervous system. CNS is brain and spinal cord and they interact with the PNS. The vertebrate brain is responsible for peripheral sensory and motor function of the opposite side of the body. Each half brain has a hindbrain, midbrain, and forebrain.

Hindbrain is vegetative function like respiratory, circulatory, and digestive with smooth and cardiac muscle. Midbrain and their neurons control primitive sensory-motor behavioral reflexes expressed through skeletal muscles. Neurons in the forebrain are responsible for more complex skeletal-motor behaviors, including those based on innate programming and learning, as well as those that depend on cognitive deliberation and decision making, and in some species consciousness, including conscious emotions. Functions are not, strictly speaking, carried out by areas. They consist of circuits of ensembles of neurons in one area that are connected by nerve fibers or axons to ensemble in other areas, forming functional networks. No area is sufficient by itself. Necessary but not sufficient.

Chapter 38: Ludwig’s Ladder

Old outdated views of evolution and believing our brains are the pinnacle of evolution held back science. A very linear ladder structure originated by Aristotle and expanded on in Christian theology. The reality is evolution changes organisms to fit their environment through natural selection rather than the belief that we are the pinnacle of creation. Useful traits can become detriments. We are newer and different but not better. We have to guard against anthropocentric tendencies.

Chapter 39: The Triune Temptress

Triune theory is stupid. Another idea founded on the belief we are superior to all other animals. Just because we have emotions that are associated with human described schema does not mean that reptiles, birds, etc. don’t feel them. Feelings didn’t arrive to control innate behaviors. This is along the lines of how consciousness typically seems to be based on soul or identity when the reality is consciousness is more like our way of containing and evaluating a snapshot of collective electric signals that we believe are under our control.

Chapter 40: Darwin’s Muddled Emotional Psychology

Even emotions have been misinterpreted, and brain researchers have been fumbling around searching for emotions in the brain by using an outdated model as their foundation. Darwin argued that emotions are states of mind that humans inherited from mammalian ancestors to adapt, survive, and reproduce. He used behavior as a direct response about how an animal was feeling.

Chapter 41: How Basic Are Basic Emotions?

William James (behaviorist) proposed we do not run from a bear because we are afraid, we are afraid because we run. Responding to danger generates physiological signals that are interpreted as fear. By 1960s the behaviorists’ influence on psychology began to wane, and a new interest in emotions as mental states arose in parallel with the cognitive revolution. Emotion like fear is the result of the interpretation that one is in danger.

The author appears sick of these silly people. Using the amygdala as an example. When threats are presented subliminally to human participants, the subject’s heart beats faster, palms sweat, and muscles tense, but he’s not aware of the stimulus and doesn’t report fear. Someone with amygdala damage can report feeling fear, despite not being able to generate bodily responses. Meaning the amygdala contributes to detection and initiation of response to danger nonconsciously, but is not directly responsible for the conscious feeling of fear. It does help to create activation feedback to the brain, helping to focus attention and amplify experience. Similar circuits to areas that control behaviors related to feeding, fluid balance, thermoregulation, reproduction, and other life-sustaining activities. Not the source but contribute to experiences.

The question about whether animals experience emotion becomes conflated with the question of whether innate behaviors are the way to measure emotions. Behavior does not represent internal experience.

Recent trends in basic emotions include approaches in which affect programs continue to contribute to emotion but in a less restrictive way. James Coan treats emotions not as subjective experiences, but as emergent states that include amygdala activity, feedback from behavioral and physiological responses, and subjective experience. The author disagrees with the subjective part being an element and says the subjective experience – feeling – is the emotion. Cognitive evaluations of situations that affect personal wellbeing. They thus require complex cognitive processes and self-awareness.

Part 9: The Beginning of Cognition

Chapter 42: Cogitation

Cognition is used in relation to thinking, reasoning, planning, deciding, etc. Cognition will refer to processes that underlie the acquisition of knowledge by creating internal representations of external events and storing them as memories that can later be used in thinking, reminiscing, and musing, and when behaving. Its dependence on internal representations of things and events, in the absence of the external referent of the representation, is what makes cognition different from noncognitive forms of information processing.

Chapter 43: Finding Cognition in the Behaviorist Bailiwick

Pavlovian conditioning is present in all classes of vertebrates, as well as in many bilateral invertebrates, including deuterostomes and protostomes, and even radial cnidarians. Some evidence also exists that it is a capability of plants, protozoa, and even bacteria. They use molecular changes within their cells instead of synaptic plasticity.

Habits work well when the environment and resources are stable. When it is volatile and resources are unpredictable, it is useful to respond flexibly on the basis of opportunities available to satisfy current needs, depending on what worked recently in similar situations. The capacity to use internal representations of goals to flexibly respond to changing environmental situations is far more limited, only clearly having been shown in mammals, and to some extent, birds.

Chapter 44: The Evolution of Behavioral Flexibility

Trial and error learning enhances fitness by selecting adaptive behaviors in a single animal, much like natural selection enhances the fitness of the species through the genetic selection of adaptive body traits. Behaviors can be learned in novel situations when they have beneficial outcomes, such as obtaining food or drink when energy or fluid supplies are low, or preventing pain or other harm in the face of danger.

Hedonic states are tied to sensory receptors that detect particular kinds of stimuli. While pleasure and pain are often treated as emotions, they are actually different. There are no sensory receptors for fear, anger, sadness, joy, or other emotions – the content is determined by the brain. The stimulus suggests but does not determine an emotional experience.

The conscious feeling of pain or pleasure when receptors are active is one of many consequences of the sensory signals that reach the brain. They also elicit reflexes or other innate reactions, increase brain arousal, motivate instrumental behaviors, and reinforce learning. Distraction can cause less pain in chronic pain patients even though the nociceptors are still responding. Only subjective pain changes. Addictive drugs are causing compulsive use because they are hijacking the habit circuits, not because of the pleasure they feel. If the responses depend on the unconditioned stimulus being a valuable outcome at the moment, then the response is goal directed; otherwise, it is a habit.

Learning by consequence only requires that the learning agent has a way to create a representation of its last action, its state when it chose that action, and the payoff received (value of outcome). Value in this context is not an emotion or feeling, but simply a quantitative representation of the payoff. Dopamine strengthens connections in the brain during these situations.

Part 10: Surviving (and Thriving) by Thinking

Chapter 45: Deliberation

A new experience requires a new round of trial and error learning. However, when life and wellbeing is on the line, random, untested options may pay off or produce potentially fatal consequences. This led to the capacity of inner deliberation in mammals.

Deliberation allows one to envision possible response options and to use practical knowledge stored in memory to evaluate and choose the one that seems most likely to produce a useful outcome. Using disparate pieces of information they can rapidly reach a decision through many repetitions of trial and error simulated internally. If you were trapped by a bear and had never been before, you could draw upon practical reasoning based on general knowledge about a similar situation. Deliberative action is effortful rather than automatic. It is related o outcome-dependent actions, in that they are flexible and goal-orientated, but responses are not based on historical relation between firsthand experience. Instead it mentally simulates possible future outcomes when planning and strategizing about how to accomplish a goal. Some previous habits and actions may have to be suppressed if a novel action is to be taken.

Deliberation is said to utilize mental models. Spatial map models are useful for most animals when accumulating knowledge in relation to landmarks. In deliberate cognition, these maps are not passively followed. They can be used to generate and compare options. Humans get a cognitive boost to their deliberative cognition via language.

Chapter 46: The Engine of Deliberative Cognition

Executive functions are prospective – they make deliberative predictions about possible future states of the world in the process of achieving goals. The cognitive activities used to achieve goals often involved many steps, over time. This is done by selecting and integrating information, dynamically updating what is being processed depending on progress toward the goal, and making adjustments when unforeseen obstacles occur.

Two key features of working memory are its ability to temporarily maintain representations and to integrate diverse kinds of representations into new unified representations. The limit of items is low so you can bundle information to store greater quantities. Bundles of stored information (memories) about related items are called schema. Updating a schema to become more elaborate is a process called assimilation. If subsequent experience contradicts the theme of a schema, the schema will often change, or the contradictory event will be reinterpreted to be consistent with the schema; this is called schema accommodation.

Schema are closely related to mental models. People use schema to generate expectations about a given situation. They facilitate thought, reasoning, and decision making, enabling the assessment of opportunities and risks of different options. Aaron Beck proposed that in mental disorders, such as depression, one develops a mental model of being a sad or excessively worried person, and becomes focused on negative self-thoughts.

Schema take advantage of the ability of the brain to complete patterns from partial information, a process called pattern completion. Pattern separation is complementary to completion – knowing what something is not. We can also group broader subjects that are in relation to each other, like what a bird is to a nest.

Chapter 47: Schmoozing

Oliver Sacks in Seeing Voices, “It is through inner speech that the child develops his own concepts and meanings; it is through inner speech, finally, that he constructs his own world.” Language does more than simply name and categorize objects and events and organize their underlying conceptions. With language also comes syntax, or grammar, which structures our mental processes and guides their operation when we are thinking, planning, and deciding. Syntax enables humans to plan actions and evaluate their consequences by anticipating many steps ahead, without performing them (a form of hierarchal reasoning). Without bringing language into deliberation, thoughts remain static and crude.

Mark Mattson described language as the quintessential example of the superior capacity of the human brain for pattern processing: “Language involves the use of patterns (symbols, words, and sounds) to code for objects and events encountered either via direct experience or communication from other individuals.” Language is the cultural tool. Early language made it possible to share knowledge about food and foes, and also other humans. Who is trustworthy and who is not or what traits made a good mate. It also allows us to transcend competition and allow cooperation, to reason about the intentions and desires of others of our kind, and to communicate with one another linguistically. Incremental learning across generations (culture).

Oren Kolodny and Shimon Edelman recently proposed that language arose by being cobbled together in early humans by way of synaptic plasticity that coupled together neural mechanisms underlying existing traits, such as nonverbal communication, serial cognition, and tool use. Once these systems were coupled it could have resulted in enhanced pattern processing, conceptual thinking, and hierarchal deliberation; communication about internal states; mind reading; gossip; and culture. If a lion could speak we wouldn’t understand it because of its frame of reference.

Part 11: Cognitive Hardware

Chapter 48: Perception and Memory Share Circuitry

Human cognitive deliberation, mental models, schemas, pattern processing, conceptualization, hierarchical relational reasoning, language, and the like are products of the kind of brain we have. To visually recognize something, its features have to match stored templates within our brain acquired by experiences with objects of that type. Meaning, the visual system partners with memory systems (which also include systems from all other sensations).

Multimodal cortical convergence areas help to form abstract conceptual memories, including aspects of schema, that enhance and supplement processing by unimodal areas. Language also involves multimodal areas. Wernicke’s, in the parieto-temporal junction, and Broca’s in the frontal lobe.

Chapter 49: The Cognitive Coalition

The various unimodal and multimodal areas involved in perceptual processing, memory, conception, and language all connect with the prefrontal cortex, which is a major locus of information convergence in the brain. Because it receives input from the more posterior-located unimodal and multimodal areas, its executive functions can control behavior on the basis of sensory-specific information, stored memories, or highly abstract conceptual representations.

Executive control guides the construction of temporary unimodal and multimodal representations, and maintains them in an active state that can be used in thinking, reasoning, and behavioral control. Different subsets of circuits can be recruited, via the prefrontal cortex, to solve problems on a case-by-case basis.

The top-down loops allow executive attention to temporarily maintain selected representations in an active state in the secondary visual cortex while the object is being constructed via bottom-up processing. The prefrontal cortex also receives inputs from multimodal areas that store conceptual representations, and can use them to anticipate what the object identity is likely to be, and thereby facilitate pattern completion of that identity in the secondary areas faster than would be possible by bottom-up alone.

It is worth mentioning that the prefrontal cortex is not a unified mass. Within the lateral prefrontal areas, a gradient of processing from the posterior to anterior exists, with processing becoming less stimulus-specific and more abstract in progressively more anterior regions. The gradient is defined by bottom-up processes. The more posterior areas primarily receive inputs from unimodal secondary sensory areas. Intermediate regions, like the dorsal lateral and ventral lateral PFC, receive a combination of unimodal and multi inputs; these areas exert top-down control over their posterior inputs. The frontal area only receives inputs from multimodal convergence zones, and creates the most abstract conceptual representations in the brain; it allows maintenance of long-term goals for future planning, and contributes to reasoning and problem solving. It interacts with dorsal and ventral lateral PF regions, and these together allow executive control over both unimodal (sensory) and multimodal (conceptual) processing in posterior areas, as well as control of deliberative behavior by way of connections to the motor cortex.

On the medial side, the anterior cingulate cortex, orbital, ventromedial, and dorsal medial cortical areas receive inputs from medial temporal lobe memory circuits and also from subcortical areas that process body signals, such as the amygdala and hypothalamus. The insula also has similar inputs. The medially located anterior cingulate cortex also contributes to executive functions, especially attention and monitoring of information processing itself.

Chapter 50: Rewired and Running Hot

Neocortical tissue consists of 6 layers. Paleocortical is missing layer 4 – granule cells. Key areas involved in working memory, and thus deliberative cognition, including the dorsal and ventral lateral prefrontal cortex and the frontal pole (areas containing granule cells). The frontal pole is believed to be the area that distinguishes humans from apes. Etienne Koechlin “It enables cognitive branching; the ability to put on hold an alternative course of action… requiring simultaneous engagement in multiple options that are not organized into a pre-established superordinate plan, such as reasoning, problem-solving and multitasking.” Related to hierarchal relational reasoning. Goals set in the frontal pole can then influence the dorsal lateral region, which connects to the motor cortex in the control of deliberative behavior.

Only primates have granule cells in layer 4 of the prefrontal neocortex. Earl Miller – between-layer interactions in the granule PFC are important in coordinating top-down and bottom-up processing. Humans have unique spatial arrangements of cells and unique patterns of connectivity within and between cell layers. Neurons in human PFC are more strongly interconnected with neurons in other cortical areas. Greater connectivity between PFC and parietal and temporal, and also within the PFC itself. Also, novel patterns of gene expression in the PFC, especially in relation to energy metabolism and synapse formation. Todd Preuss, “Rewired and running hot.”

Some of the novel aspects of human cognition are prone to malfunction in conditions such as autism and schizophrenia. They have not fully been tested by natural selection for their fitness, and may be more susceptible to genetic perturbation than older, more established traits.

Broca’s and Wernicke’s are in apes but ours have the pattern and strength of connectivity between them. They are interconnected with multimodal areas in the parietal, temporal, and frontal lobes. As mentioned before, the ability to use language in hierarchal relational reasoning (cognitive branching) depends on working memory executive functions of the PFC. Language would have evolved in steps but required mammalian cognitive processes like being able to focus attention on external stimuli, form memories about them, and to use the memories as internal representations to guide behavior in the absence of the actual stimulus. Working memory gives a power boost to holding more info while deliberating.

In the end, we aren’t that different. We may prefer the way we live but in the end there is no scale, other than survivability. If species longevity is the measure, we will never do better than ancient unicellular organisms.

Part 12: Subjectivity

Chapter 51: Being There

The inner awareness of external stimuli – the knowledge of what is being perceived – is a prime example of what is called conscious experience. Consciousness allows us to experience the present and imagine the absent. To envision one’s past, present, and future to make possible the ability to transcend the survivability options bestowed upon our species by natural selection, and/or instilled in an individual by goal-directed in instrumental learning – both of which are based on behavioral strategies that were successful in the past.

Split brain patients can give verbal reports about information in the right half of visual space (language control in left hemisphere) but cannot name left hemisphere info. They can however, nonverbally respond to the stimuli by pointing or grabbing objects with the left hand. When blindfolded, they can name objects in their right hand but not left. Some patients would physically do stuff and confabulate the reason for why verbally. A form of cognitive dissonance. Mismatches between what one expects and what happens create a state of inner discordance, or dissonance. Because dissonance is stressful, it demands reduction in order to meet the human need for cognitive equilibrium. Also known as post-decision rationalization. 

Knowledge and Belief + Action (Inconsistent with belief) = Dissonance -> Change Knowledge/Belief OR Change Action OR Change Action Perception = Dissonance Reduction

Chapter 52: What Is It Like to Be Conscious?

If you pair an electric shock with subliminal stimulation, the subject will react to the subliminal unpaired stimuli as if they were getting the shock. Meaning they are unconsciously perceiving an image. As Freud said, consciousness is only the tip of the mental iceberg. When stimuli are reportable, areas of the visual cortex and areas of the general cognitive cortical network that underlies working memory are activated, especially areas of the PFC. When a verbal report can’t be made, only the visual cortex is. This indicates that in order to have a phenomenally conscious and verbally reportable experience of visual stimuli, sensory processing in the visual cortex has to be further processed by cognitive control networks underlying working memory.

The foci of some contemporary physicalist theories of consciousness:

• Attended intermediate representations (Jesse Prinz)
• Attention schema (Michael Graziano)
• Attentional amplification (Michael Posner)
• Autonoetic consciousness (Endel Tulving)
• Dissociable interacting systems (Daniel Schacter)
• Dynamic core (Gerald Edelman, Giulio Tononi)
• First-order representations (Ned Block, Victor Lamme)
• Global workspace (Bernard Baars)
• Global neuronal workspace (Stanislas Dehaene, Lionel Nacchache, Jean-Pierre Changeux)
• Higher-order representations (David Rosenthal)
• Higher-order representation of a representation – HOROR (Richard Brown)
• Integrated information (Giulio Tononi, Christof Koch)
• Microtubules (Roger Penrose, Stuart Hameroff)
• Operating system (Philip Johnson-Laird)
• Hierarchal predictive inferences (Karl Friston, Andy Clark, Anil Seth)
• Social interactions (Christ Frith, Uta Frith, Nick Shea)
• Supervisory executive system (Tim Shallice)
• Verbal interpreter (Michael Gazzaniga)
• Time-locked multiregional retroactivation (Antonio Damasio)
• Working memory episodic buffer (Alan Baddeley)

Our conscious mind is vain. It believes it is where the psychological action is. But we are more like the driver behind the wheel of a Tesla, where we can take control if needed, but the rest of the time we can consciously think about something else.

Conscious awareness is often missing the reason or motivation behind actions. We know what we did but not why. So, in the face of disunity, consciousness must have some sophisticated way of re-scripting one’s history to account for responses that it did not intentionally will. A defense tactic, a way of defining and protecting our understanding of our self.

Chapter 53: I Want to Take You Higher

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Chapter 54: Higher Awareness in the Brain

The frontal pole is well suited for high-level conceptual processing and is, in fact, generally considered to have the greatest capacity of any brain area for conceptual processing. Thus, dorsal lateral and ventral lateral PFC areas are higher-order anatomically with respect to posterior unimodal and multimodal processing areas, and the frontal pole is higher order with respect to all of these. Task specific goals are thought to be related to DLPFC and FP to long-term goals and in cognitive multitasking and hierarchal reasoning.

Part 13: Consciousness Through the Looking Glass of Memory

Chapter 55: The Invention of Experience

Hermann von Helmholtz, “experience, training, and habit influence our perceptions because they allow us to have “unconscious conclusions” about what is present that do not necessarily fully match with the sense data available.”

The predictive coding hypothesis: Top-down unconscious predictions based on retrieved knowledge, or memories shape what we consciously see.

Top-down predictions based on current mental models, corrections, and dissonance seem to have an emergent pattern in economics.

Chapter 56: Ah, Memory

Memories that can be verbally described are explicit or declarative. Implicit or procedural don’t require conscious awareness (conditioned response, habits, skills, or procedures). Explicit memories are not literally conscious memories until they are retrieved from storage and brought into working memory.

Semantic memories allow you to act appropriately with generally well understood objects like apples vs red marbles and cherries. Acquired through experience but not tied down to those specific experiences in any way. Episodic are linked to episodes from which they arise. They also include the experiencer in the memory and are personal. Consciousness of semantic memory requires noesis, an awareness of facts based on stored internal representations of objects and events. Consciousness of episodic requires autonoesis, an awareness of you, part of the experience. Mental time-travel. Remembering your place in the past allows projection of a similar experience in the future.

When you are aware of who you are, you are drawing from your self-schema, which is what underlies your self-concept. Your self-schema includes your skills and abilities; your foibles; your social roles; your psychological attributes; your self-worth; how you look; how you feel and act; how your body responds in certain situations; what you expect your future to hold; how you feel about your family, friends, enemies, colleagues, acquaintances, and even your possessions, and un-possessed but desired things of either the natural or man-made world. But your self-scheme is not static. You change over time and are different in different contexts or situations. A working self.

The concept of self is dependent on the psychological conceptions that are embedded in his or her culture and its native language. The unique human cognitive system is capable of suprapersonal representations that can be shared with others.

Chapter 57: Putting Memories in Their Place

Areas of the medial temporal lobe (perirhinal cortex, parahippocampus, entorhinal cortex, and hippocampus) play a role in explicit memory. The two perception memory streams from the visual cortex converge in the hippocampus, allowing objects to be perceived in the context of complex scenes. The what and where are a start towards episodic memory and the hippocampus also encodes the when. The MTL areas are also strongly connected to the MPFC.

The temporal pole, viewed as a neocortical semantic/conceptual hub that integrates across various unimodal and multimodal inputs to create general, abstract concepts and schema, analyzes similarities and differences between individual items to form generalizations and inferences about what something is and is not, and makes possible item recognition from its appearance, sound, taste, touch, small, and/or name. It is one of the first brain areas affected by Alzheimer’s disease and accounts for some of the early memory problems.

When episodic memories become semanticized, they lose dependence on the medial temporal lobe and come instead to be neocortically based.

Brain areas that have been implicated in self-processing overlap, to some extent, with areas of the so-called default mode network of the brain, which is active during passive mental states, such as undirected mind wandering.

Chapter 58: Higher-Order Awareness Through the Lens of Memory

Critics of HOT argue that the PFC lacks the fine-grain representation of our rich quality of perceptual experience. This falls through when consciousness is viewed as a top-down construction based on combinations of sensory, memory, and conceptual representations rather than purely sensory dictated perceptual experience.

The frontal pole, and its conceptual self-awareness, may underlie our ability to use knowledge about one’s self to understand the minds of others.

An issue with referring to one’s self as “I” is the assumption that you are operating at a higher order of consciousness and you are a part of and in control of the current operations. Rather than a mix of perception, memory, and mental models. The brain takes time to process, so you are never in control of the now.

At a minimum, a theory of consciousness ultimately has to account for at least the following kinds of states: those that are about fleeting and meaningless perceptual events (events such as a flash of light or a brief sound); lasting but still meaningless perceptual events (an unfamiliar stimulus in isolation, such as a street sign in a foreign language); meaningful perceptions shaped by memory (recognition of a common object alone or in the context of a scene, such as an apple in a bowl with other fruits, or a song from its opening line); absorbing episodes of daily life (a conversation with a friend, an unpleasant encounter with a superior, the taste of a delicious dessert, an engaging piece of music or a painting, contemplation of one’s own existence); consuming illness (chronic pain, pathological fear, anxiety, or depression); and perhaps many others.

Part 14: The Shallows

Chapter 59: The Tricky Problem of Other Minds

Every scientist is also a layperson and brings everyday assumptions into the lab. We study psychological processes because we have them and want to know more. But we have to go beyond these intuitions and analogies when being scientists. However, our language is inherently anthropomorphic, and as a result our concepts and thoughts tend to lean in this direction too. The attribution of human mental states to animals is believed to have played a key role in their domestication, which occurred during the agricultural revolution in the late Neolithic period, around 3000BC.

Our strongest biases are not freely available to our conscious mind. If you aren’t aware of a bias you can’t guard against it. The best way to demonstrate consciousness in animals should be to compare conditions under which the behavior is best explained as being dependent on consciousness, and cannot be reasonably explained in terms of some nonconscious process.

Chapter 60: Creeping Up on Consciousness

Heyes argues that animals don’t need a theory of mental consciousness to predict the behavior of other animals any more than they need a theory of toxicology when choosing not to eat rotting food – visual stimuli and odors are sufficient.

Chapter 61: Kinds of Minds

We have to remember that even in humans PFC activity is not a surefire way to implicate consciousness in behavior, since PF circuits process information both consciously and nonconsciously.

Part 15: Emotional Subjectivity

Chapter 62: The Slippery Slopes of Emotional Semantics

Scientists have been sloppy with the words for emotions. Fear, for example, describes the feeling of fear, physical responses of fear, motivation to perform avoidance behavior, cognitive appraisals, etc. Scientists typically approach their work from their personal vantage point, based on intuitions about some phenomena they are interested in understanding. Even though all scientists know that correlation does not equal causation, some things seem so obvious that a casual connection is simply presumed, and becomes a scientific truism, a fact, a dogma, and goes unquestioned.

Confirmation bias affects scientists too. For example, the amygdala is assumed to be the fear center. The connection was made in the 1950s, but the idea began to heat up as a result of research done by Bruce Kapp, Michael Davis, and the author, using Pavlovian fear conditioning in the 1980s. They found the amygdala was an essential part of the brain circuitry that controls behavioral and physiological responses elicited by the conditioned threat. Since they were studying “fear” conditioning, the idea naturally arose that a state of fear was what got conditioned, and that the amygdala is thus a fear center. It was responsible for the so-called fear response, not the generation of the conscious feeling of fear.

As a scientist it is extremely important to be careful of your wording and to predict potential pattern-completion in the media or hyperbole.

Chapter 63: Can Survival Circuits Save the Day?

To avoid confusion when talking about aversion and resource allocation, behaviors like fear should be replaced with survival behaviors, and the circuits labelled survival circuits. The circuits that control hardwired (instinctive) behaviors. This isolates the objective function from the presumed mental state (feelings).

It has long been assumed that when a medication alters defensive behaviors in animals it is because it changes the fear or anxiety circuits. This effort has been so unsuccessful at reducing fear and anxiety circuits in humans that pharmaceutical companies have ceased searching for new treatments.

Chapter 64: Thoughtful Feelings

To the author, human emotions are autonoetic conscious experiences that are cognitively assembled, much like any other autonoetic conscious experience. The idea of unconscious emotion is an oxymoron: If you don’t feel it, it’s not a feeling, not an emotion. Nevertheless, nonconscious factors contribute. Emotions are a type of constructed schema. Without the self being part of the experience, the experience is not an emotional one. Although, not every experience that involves the self is an emotional one. The noetic awareness that danger is present is not the same as a state of autonoetic awareness in which you know that you are the one in danger.

Barrett describes emotions as conceptual acts. Gerald Clore and Andrew Ortony note that emotion schema are “ready made frames” that we use to interpret the present, remember the past, and anticipate the future.

We experience our various emotions differently because each involves a particular schema that contextualizes and interprets the present state differently. Because schema are built up by the accumulation of memories, the earliest emotions one experiences as a child are simpler than the ones that are experienced later. Through assimilation of additional information, a particular emotion schema becomes more complex, and when new information is contradictory, the schema is modified. Thereby, new experiences result in more specific definitions of emotion. Language may not be necessary for experience but it helps to differentiate them.

If emotions are subjective, why do they seem so universal? What is universal about fear, for example, is not the details, but rather the concept of fear. All organisms face physiological and/or psychological threat. These are among the most significant stimuli they will encounter in life. If the organism has a language, they will give a term to the stimuli they feel when confronted with threat.

A common criticism is that babies put their emotions on display, despite the fact they cannot speak. But they are not unambiguous indicators of feelings because as we’ve seen, responses and feelings are controlled by different circuits in adults, and the circuits that control response mature earlier than the conscious experience ones.

The closest we ever get to the truth of an experience is during it. All recollection afterwards is top-down and can be changed by the very act of trying to retrieve it. Self-narrative revision. They get edited, embellished, and assimilated with other categories available. Writing exposure therapy (WET) gets the person to write about their trauma and modify and clarify the narrative. It seems to have a faster effect than cognitive behavioral therapy and medications.

Chapter 65: Emotional Brains Run HOT

The multistate hierarchal model is the conscious experience of emotion resulting from the higher-order representation of nonconscious lower-order states by the higher-order network (dorsal and ventral lateral PFC and frontal pole). Key to the experience of perception, memory, and emotions.

In the case of seeing a snake at your feet: image from eyes to visual cortex, secondary visual circuits (some using memory of past perceptions to filter signal) distribute their output to PF areas (especially dorsal and ventral lateral PFC). Secondary sensory circuits also send outputs to circuits that add additional semantic and conceptual meaning to the representations (including medial temporal lobe and neocortical areas, such as the temporal pole, among other multimodal regions). These latter circuits send their outputs to the medial/insula PF areas, which connect with the higher-order network; some also connect directly with the higher order network. On the basis of the various prefrontal representations by the higher-order network, top-down control over processing is initiated and influences ongoing posterior perceptual, mnemonic, and conceptual processing. As these processes unfold, interactions within the higher-order network begin to shape a perceptual conscious experience of the threatening stimulus and its context. At this point you have achieved a noetic state of consciousness – an awareness that harm is present – but are not autonoetically conscious emotional state – one in which you are aware that you are in the presence of harm. This gives high level deliberative cognitive control over instrumental behavior.

By way of sensory inputs from thalamic sensory areas and secondary cortical sensory areas (so-called low and high roads to the amygdala), threats activate the defensive survival circuitry, and initiate a cascade of events in the brain and body. TLDR: amygdala influences top-down conceptual control over sensory processing, memory retrieval, and decision making, as well as higher-order construction of emotions. Also raises arousal – vigilant scanning for clues about the cause, with semantic memories focusing. Insula cortex retrieves messages from amygdala and connects to the medial prefrontal areas then to higher order prefrontal network. Adrenaline from adrenal medulla activates nerves in body cavity that sends signals to neuromodulatory systems in the brain, further enhancing brain arousal. Cortisol also travels to the brain (slow hormone effect).

To summarize, conscious emotional experience results from the processing of various nonconscious, lower-order ingredients by the PF higher-order network

1) perceptual information about the triggering event

2) retrieved semantic and episodic memories

3) conceptual memories that add additional layers of meaning

4) self-information via self-schema activation

5) survival circuit information

6) brain arousal and body feedback consequences of survival circuit activation

7) information about what kind of emotional situation might be unfolding as a result of activation of one’s personal emotion schema

The higher-order network attends to, monitors, and controls processing of these nonconscious lower-order signals and uses them to introspectively access, label, and experience the resulting autonoetic conscious emotional state. If your fear schema has been auto-completed by a threat, the experience will fall in the general domain of fear.

It is important to note that once you have conceptualized that you are afraid, this awareness may, in top-down fashion, be a sufficient trigger for initiating the kind of brain and body arousal elicited by certain external threats.

Active inference and predictive coding (Lisa Barrett)

Chapter 66: Survival Is Deep, but Our Emotions Are Shallow

The author proposes that emotions are human specializations made possible by unique capacities of our brains. Our early hominid ancestors required evolved language, hierarchal relational reasoning, noetic consciousness, and reflective autonoetic consciousness. These made it possible to integrate ancient survival circuits into self-awareness, framed in terms of semantic, conceptual, and episodic memories, interpreted in terms of personalized self and emotion schema, and used to guide behavior in the present and also to plan for future emotional experiences. Making emotions the mental center of gravity for the human brain, fodder for narratives and folktales, and the basis of culture, religion, art, literature, and relations with others and our world.

Rather than being an inherited vestige of our primate or mammalian past, it may be an exaptation. Exaptations are useful traits that arise as a by-product of other traits, and because of their value, come under genetic control through natural selection. Emotions might be the result of two other exaptations:

Language – Kolodny and Edelman suggested it arose from synaptic plasticity that coupled neural mechanisms underlying nonverbal communication, serial cognition, and tool use.

Language may have enabled autonoesis (awareness of “self as subject,” as opposed to “self as object”). Emotions, being a form of autonoesis, were then inevitable as conscious experiences of one’s self in biologically or psychologically significant situations in life. Biological are tied to survival circuits and psych lack a fundamental connection.

This doesn’t mean there are no connections to our animal history, since the most fundamental emotions are those to which ancient survival circuits contribute. But, they do not define the content of emotional experience.

Humans can attribute value to things. Meaning they can ask, “How dangerous is this threat to me?” Other animals can represent value but only humans can make it personal. In this sense, an emotion is the experience that something of value is happening to you.

Just because emotions and self-awareness are unique to humans, it doesn’t make animals primitive reflex machines. Even humans undergo nonconscious cognitive and behavioral routines. Thinking pets have the mental capacity we do is fun in normal life, but not in science.

Epilogue: Can We Survive Our Self-Conscious Selves?

Hakwan Lau – In Consciousness We Trust. Consciousness, especially autonoetic consciousness, has a darkside – it is the enabler of distrust, hate, avarice, greed, and selfishness. Then again, it could also be our savior.

Humans developed language; hierarchal relational reasoning; representation of self versus other; mental time travel. Autonoesis was the result.

Autonoesis is proposed to depend on the frontal pole, which has novel components and that interact with lateral prefrontal areas to form the higher-order network; enriched connections between the higher-order prefrontal network and lower order processors (including other prefrontal areas and perceptual, mnemonic, and conceptual processors in the occipital, temporal, and parietal lobes); and novel cell types (granule cells?) and molecular/genetic mechanisms that fostered enhanced processing within the higher-order network and between it and lower-order processors.

Aldous Huxley mentions that we rose above the brutes because of language. However, people can also become victims of their own words. Language can give us personal pronouns that separate “me” from “us” and “them”. We build social groups, clans, tribes, religions, kingdoms, and nations on this basis, and shun, isolate, harm, and even kill one another to protect beliefs that define the groups with which we choose to affiliate. The selfishness of genes pales in comparison to our self-conscious mind and its convictions.

Beliefs are not just products of language or culture. They also depend on other special capacities that are intricately entwined with language – hierarchal cognition, self-awareness, and emotions. When these blend seamlessly, social systems that work for the greater good can thrive. But when emotions are at odds with our reasoned thoughts, or when either is corrupted by beliefs, or when personal interests are pitted against the values of a culture at large, or against the needs of our species as a whole, humans suffer.

Imagining the unknown inspires us to find new ways of existing. Our thirst for knowledge has led to scientific and technological discoveries that have made life easier in many ways. We don’t have to forage for food in dangerous settings-no predators. We combat seasonal changes in temperature, we have access to medications, and surgical procedures. We can also electronically communicate with anybody in the world instantaneously.

The internet has come at a cost. It has made it easier to be self-centered by facilitating realignments of interests that oppose the common good, challenging commonly accepted beliefs through hearsay and rumor, and even outright lies. False assertions gain acceptance through repetition. This has led to science being undermined, attacking social structures and survival requirements for those in need, and the governments original checks and balances against tyranny.

The global temperature is rising, along with unusual weather patterns, forests are burning, deserts are expanding, seas are rising, species extinction is accelerating… Adam Frank (astrophysicist) believes those who are concerned are right to worry. Lynn Margulis (endosymbiotic theory of multicellular life) says Gaia is a tough bitch. Our planet has survived significant geological disasters and mass extinctions in the past and will persist. Not in a way that will support the current configuration of organisms though.

Autonoetic consciousness is ultimately personal and selfish, and at its worst moments, narcissistic. According to Christophe Menant, the root of all evil. At the same time it may be our sole hope for a future.