By Chet Yarbrough
Biology and Human Behavior: The Neurological Origins of Individuality, 2nd Edition
By: The Great Courses
Lecturer: Robert Sapolsky
Robert Sapolsky is an author, American neuroendocrinology researcher, and doctor of neuropsychology, educated at Harvard and acting professor at Stanford.
Sapolsky’s lectures begin with optimism. He infers one can understand the biological origin of human behavior. However, as the lectures progress one becomes skeptical. By the end of Sapolsky’s lectures, the source of human behavior seems too complex for human understanding. In a future age, it may be possible to reduce uncertainty, but determination of the sources of human behavior are likely to remain a probabilistic endeavor.
Sapolsky begins with neurological, physiological, endocrinological, genealogical, and environmental influences on behavior but ends with no definitive origin for human behavior.
This is not to say these lectures are not interesting, but science is far from understanding how any discipline can effectively or accurately identify the sources of dysfunctional human behavior. Cures for psychological maladies remain elusive because of the complexity of their origin.
There is no nerve that can be cut, no drug that can be administered, no gene that can be removed, no environment created that singularly cures abnormal human behavior. Sapolsky is saying the origin of human thought and action begins with genetic history, is influenced in the womb, is subjected to hormonal disruption, lives to be changed by environmental circumstances, and dies either early or late depending on the circumstances of life.
Sapolsky begins his lectures with a lesson in physiology and discussion about cells and the nervous system and how it works.
He explains limbic and autonomic nervous systems. A limbic system is where subcortical structures meet the cerebral cortex. It influences the endocrine system and the autonomic (breathing, heartbeat, and digestive system) functions of the body.
Sapolsky explains how regulation of body function is affected by hormones that come from many organs of the body. These hormones affect brain function (which is also a hormone producing organ) that have a great deal to do with how one acts. The physiology of the nervous system and blood circulatory system carry hormones throughout the body.
Sapolsky goes on to explain evolution of behavior that comes from genetically inheritable social history. What is revelatory is the myth of evolution based solely on a genetic singularity which preserves itself at all costs.
Sapolsky argues preservation of species, not specific gene preservation, is the key to understanding evolution. (This is a partial disagreement with the “selfish gene” postulated by Richard Dawkins.)
The example Sapolsky offers is the Wildebeest herd that plans to cross an alligator infested river.
An early interpretation of that crossing is that a leader of the herd voluntarily steps into the river to sacrifice itself to allow the herd to cross the river while it is being feasted upon by alligators. Sapolsky explains the Wildebeest is not sacrificing itself. Careful observation shows an older Wildebeest is forced into the river by the herd. It is not a voluntary action but a heritable social behavior of the herd to preserve itself.
Sapolsky identifies myths about what causes abnormal human behavior. The idea that testosterone levels are a cause for aggression is untrue. The National Institute of Health found that increased or decreased levels of testosterone have a weak correlation with aggression. Sapolsky notes that testosterone levels vary based on environmental circumstances and interaction with other hormone producing organs. It is not found to be a hormonal cause of aggression.
Every country of the world is populated with people like the wildebeest. Until the world is one herd, it seems humans are destined to lose their way as a species. The river to cross is the world’s environmental crises. With disparate herds in the world, the alligator in the river (our environment) will eat us all.