This final lecture in the course "Human Behavioral Biology" with Robert Sapolsky explores how everything learned in the course leads to a profound biological understanding of individuality built on a bedrock of randomness and determinism. What does this mean to us as individuals and to us as a society?

The challenging question about where free will enters the picture is discussed. If each of us is just a few neurons, neurotransmitters, and genetic variations on receptor proteins away from being like one of them (whether you choose to imagine someone whose body or mind is only a little bit different or someone who you love and admire or someone who you cannot stand), what is the real nature of being human?

Is each of us just the output of the biological accidents that make up a human brain and the body with which it is intimately interacting through blood and neuron?

I started posting notes summarizing videos for this course on 18 March 2013 ( I've written notes for each of the 24 previous videos in the course. This is my last set of notes for this course!

BIO 250, HUMBIO 160: Human Behavioral Biology is the 54th free on-line course I've "completed" since I started taking such courses in 2008. Since I only took about 30 courses for my BA degree from Binghamton University, I am pretty sure I now deserve an edutainment degree for this effort. However, only 18 of those courses (12 offered statements of accomplishment while the other six involved no independent assessment of my efforts), including this one, were pursued with a significant intensity of effort.

The whole course has been about biologically answering the question why did a given behavior occur? The course has asked the question for both benign human social behaviors and for disastrous ones (violence, mental illness, etc.). Exploring the biological causes of these behaviors raises the troubling question: Whose fault is it when an abnormal behavior occurs?

Sapolsky feels that the whole course in explaining the neurological, hormonal, experience, genetics, and evolutionary bases of human behavior challenges the notion of free will, culpability, and responsibility. Both the questions whose fault is it? and Who is worthy of praise for "good" behaviors? are equally interesting.

"Where are these behaviors coming from?"

500 years ago, epilepsy was well understood: it was certainly caused by demonic possession. Today if an epileptic strikes someone in the midst of a seizure they are no longer held culpable. For the past hundred years or so we've been taught "it's not him, it's his disease". Which is a major change from burning them at the stake. We now understand there is a difference between the individual and the action potential storms that sometimes occur in an epileptic's brain.

Since John Hinkley's attempted 1981 assassination of President Reagan with his paranoid schizophrenia and successful insanity defense, public opinion that "he's getting away with it" has increased. The Insanity Defense Reform Act of 1984 has made it more difficult to use the insanity defense and now America incarcerates many of its mentally ill. Can and should we distinguish between John Hinkley and the dopamine abnormalities in his brain?

Parents, teachers, and guidance counsellors also struggle with these distinctions of culpabilities with the biology of learning disabilities and dyslexias. Are such kids "lazy" or "stupid" or is their biology to blame? "An awful lot of people in positions of power, parents, et. al., have still not gotten very good at drawing the line between the essence of who that person is and the biological constraints that are superimposed on top of it.

At some point in considering the distinction between the biology of "them and their disorders" we must consider the biology of us, the biology of our individual differences, quirks, and idiosyncrasies. Am I who I am because of my biology? Or because it is me? What's the difference?

What are we to make of subtle neuropsychiatric "conditions" which lie in the netherland between normal and abnormal?

Schitzotypalism is not a psychiatric disorder (it is a much milder form of schizophrenia with loose associations and the like but in more appropriate contexts; see these notes for a broader discussion

What is the difference between us and our quirky behavior and "them" and their psychiatric disorders?

Sapolsky reviews cases of frontal lobe damage causing abnormal behavior (Phineas Gage and other examples are discussed in these notes Each of us has a differently wired frontal cortex which is responsible for our style, quirks, intellectual strengths and weaknesses. Are our disinhibitions and inhibitions the result of too many or too few neurons in the right place? Is it OK when our frontal lobes make mistakes? What is a mistake?

Huntington's disease (more details about Huntington's are in these notes is a horrible neurological disorder that gradually results in an uncontrollable writhing. A few years before Huntington's becomes a neurological disorder, it starts as a psychiatric disorder of disinhibition (he gives the examples of a happily married man who suddenly in his 40s punches someone at work, has an affair, gets into a fight in a bar, and embezzles all the funds from work). The damage in the frontal cortex precedes the damage in the motor pathways. Huntington's may have a selective advantage in its promiscuity (onset around age 40) before the neurological devastation begins. It is a genetic disease involving a single gene!

How many non-disease single gene variations does each of us have? Is one of those responsible for this or that behavior in you or your neighbor? Would knowing that your neighbor makes their choices one way because of their brain wiring (either caused by developmental accidents or genetic ones) change the way we think about who we are and how we choose? Does it clarify what we are really free to do? Are we free to behave in a way in which are brains are not wired?

Frontal cortex damage problems remind us that every day we all have thoughts that are boastful or lustful or petulant, etc where we would be horrified if anyone knew what we were thinking. With frontal cortex damage, we say what we are thinking revealing just how tenuous our behavior really is.

Tourette's disease involves aggressive and sexually inappropriate gesturing, facial ticks, animal sounds, extensive cursing. The essence of a Tourette's patient has nothing to do with their behavior. And in milder forms, it is just individual variation. It tends to manifest in adolescence and affects girls more than boys.

PANDAS (pediatric auto-immune neurological disorders associated with streptococcal infections) refers to the 1 in 10,000 kids who recover from a strep infection and then develops symptoms akin to Tourette's. PANDAS can sometimes be "cured" by giving immunosuppresive drugs. Future infection may cause a recurrence of the behavior. Evidently, the immune system pierces the blood-brain barrier and affects us in places where the immune system ought not go resulting in antibodies that attack your own brain. Adult Tourette's patients and those afflicted with obsessive-compulsive disorder have a higher than chance levels of antibodies in their blood against constituents of their nervous systems and a higher than expected rate of childhood diseases.

Are we necessarily the behaviors we exhibit? If our behavior is somehow different from what we would value, does that mean our biology is doing stuff with our bodies that we need not or ought not own? Can and should we separate a person from their behavior? Can and should we sanction or praise someone's behavior if it is beyond their control?

People with temporal lobe personality (see these notes for more details tend to be more interested in religion. How are we supposed to make sense of the other if they may be the product of a classifiable brain type? How are we supposed to make sense of us if we are the product of our brain types? Are we simply random variations of the type of brain we ended up with? Is that fair? How can we accept that?

OCD (obsessive compulsive disorder which is also discussed in the notes at has links to strep infections and genetic components. Brain imaging studies suggest that people with OCD have increased metabolic rate in the basal ganglia (see here for more details which is a part of the brain involved in movement. Maybe OCD is an itch in the motoric subsystem of the brain? OCD patients treated with SSRIs (selective serotonin reuptake inhibitor, for more details see these notes respond with reduced activity in their basal ganglia.

Jerusalem syndrome is a psychiatric disorder that is only acquired in Jerusalem. After ruling out all other diagnoses, if a highly religious person on their first trip to the holy land who travels on their own and suffers from jet lag may become distraught that Jerusalem is just like any other modern city and turns their hotel room sheets into a toga and goes into the streets preaching that we must return to simpler ways. There are 50 cases per year in Jerusalem. After returning to the states, the person returns to being "normal".

Stendhal's disease is the onset of vertigo and nausea and ecstasy upon seeing the great art in Florence.

Trichophagia or Rapunzel syndrome is a disorder of eating hair obsessively. What is the evolutionary selective advantage of this one?

Apotemnophilia is a disease of people who can only become sexually aroused by amputees.

Acrotemophilia (or Body integrity identity disorder, BIID) is a disorder of people who feel that they were meant to be disabled by amputation of one of their limbs.

In another case a stroke in a gang member led to becoming obsessed with Polka music.

There are countless ways in which things can go wrong in our brains. As psychiatry categorizes more and more patterns, pretty soon every single one of us will have two or three bone fide psychiatric conditions.

What are we to make of this? Is this a profound window into the nature of our individual differences? Are each of us two or three neurons and 1 or 2 cc of neurotransmitter away from a psychiatric disorder? Do our brains and bodies give us our behavior and we just ascribe the label "our choice" to the result?

What is the difference between a psychiatric disorder and "normal" brain functioning?

Every one of us has elements of some of these psychiatric disorders. Sapolsky admits to some obsessive intrusive thoughts such as counting steps or thinking about the YouTube video "Charlie Bit Me" (

The same biology for schizophrenia (a thought disorder which frequently involves metamagical thinking; for more see these notes in a milder form results in people interested (but less pathologically so) in metamagical thinking and in the mildest form allows each of us to have a fantasy in the supermarket line.

The same biology that causes "them and their diseases" becomes us and who we are.

Now that biology is revealing the details of the genetics and brain science involved in tastes and religion and risk tolerance and faithfulness and ... everything. As biology "explains" everything about human behavior we become uncomfortable because it challenges the notion that we are utterly unique, we believe that each of us is a flame of individuality that ought not be reduced to a category of neural firing patterns subject to genetic and chemical constraints.

Arthur C. Clarke's story "One Billions Names of God" has a scene where as we name the names of God a star goes out. This metaphor captures the idea of our fear that as we turn each aspect of our personalities into a biochemical pathway, we lose a bit of our individuality, a bit of what makes us who we are.

Sapolsky argues that even if science understood everything, we could still be moved by the experiences of life. Moreover, every time science answers one question many more new ones get generated which are often more interesting than the first question. It is an infinite fractal of knowledge to discover.

Quote from J. B. S. Haldane "Life is not only stranger than we imagine, life is stranger than we can imagine." The actual quote is "I have no doubt that in reality the future will be vastly more surprising than anything I can imagine. Now my own suspicion is that the Universe is not only queerer than we suppose, but queerer than we can suppose."

Sapolsky adds: "The purpose of science is not to go cure us of the sense of mystery, the purpose of science is to constantly reinvent it."

As biology unravels the nature of human behavior and identifies how we tick and how we can control the way we tick, what should society do?

Sapolsky emphasizes that in all the continua of biology and behavior in the course, "there but for the grace of god and a couple of neurotransmitters and three or four more receptors could go I".

Should our empathy, care, understanding, and protection extend to cover even the most biologically "damaged" among us? Even those who are psychologically damaged? Even our so-called criminals?

Should we empathize with murderers and rapists and terrorists as victims of circumstance and biology?

Does understanding the biology that makes us unique along many continua of mental disorders allow us to better protect and care for each other? Is there a role for judgement of others when we know that it is their biology that is causing their "erroneous" behavior?

Is being a healthy person merely saying "we merely have the same diseases that everybody else does"?

Sapolsky argues that understanding our biology should make us more compassionate. Should it?

Should we celebrate and reward those whose biology gives us joy such as top-level scientists, athletes, entertainers, etc. If their biology gives them those faculties should we treat them as "special" in any way?

How does understanding this biology affect you and me?

The concept of modulation was discussed repeatedly in the course where instead of directly causing some behavior, it just amplifies or dampens some pre-existing tendency. Is the point of the course that causality doesn't exist as everything is modulated by a large set of factors?

Sapolsky advises that although it is a huge amount of work to collect the data to understand some phenomena in human behavior with its litany of contingent clauses, it is necessary to synthesize and intuit its nature in order to work to achieve one's goals.

Our biology gives us the capacity to sin, to do wrong, so likewise, you have the power to attain a state of grace through the work you will do.

Oppenheimer after the successful atomic bomb test said something to the effect that now even physics has sin.

"Even though its complicated, you gotta do something."

In archeology, best practice is to excavate only part of a site so that future generations with better tools can come back and learn more. Metaphorically, Sapolsky suggests that we should be aware that people in the future may be thinking very, very differently.

Sapolsky ends by arguing that you don't have to choose between being compassionate and scientific.

What do you make of our predicament as biological creatures with biological brains whose function clearly proves that everything we do is ultimately a function of biology?

What is the impact of this realization? Does it prove that there is no (or little) free will? Does it provide a perspective to help us better appreciate our humanity? Does paying too much attention to our biology blind us to choices, capabilities and possibilities that we may have that biology doesn't yet imagine that we have?

How might science and biology inhibit us from better understanding our humanity? How might science and biology help us better understand our humanity?

What does it mean to be an individual human being?