Tuesday, December 27, 2011

Robert Sapolsky Talks About the Biology of Human Behavior

We think in categories. But there are these problems. The first one being that when you think in categories you underestimate how different two facts are when they fall in the same category. When you think in categories you overestimate how different they are when there happens to be a boundary in between them. And when you pay attention to categorical boundaries you don’t see big pictures.

The speaker was leading neuroscientist Robert Sapolsky addressing a 2010 class in human biological behavior at Stanford. Dr Sapolsky is a leading researcher into how stress influences behavior, an endeavor that ranges from tracking brain circuitry in lab animals to studying baboons in the wild. He also possesses that rare gift of being able to communicate complex topics to the general public, with a number of highly readable mainstream books to his credit, including “Why Zebras Don’t Get Ulcers.” 

My whole approach to mental illness owes much to Dr Sapolsky, and it has been that way for years.
“How many people believe in free will?” he asked. He smiled. “That’s going to change,” he advised. Then he addressed the classic nature-nurture debate. “Who thinks human nature is all explained by nature?” he asked. “Who thinks it’s all explained by nurture?” Another smile. “Who thinks there’s a magnificent fascinating nuanced interaction between nature and nurture?”

The categories thing again. Thinking in categories does make it easier for us to remember stuff and evaluate stuff, Dr Sapolsky acknowledged. But there are a bunch of problems, especially if you overestimate the importance of the bucket you live inside of. “And thus everything about this behavior is explained by  - a gene, a neurotransmitter, a childhood trauma, a living inside one bucket.”

Human behavior is harder than that. On one hand:

Sometimes the stuff that’s going on in your body can dramatically influence what’s going on in your brain. (Such as the food we eat, with the notorious example of the “Twinkie defense.”) 

And on the other:

Sometimes what’s going on in your head will affect every single outpost in your body. (Such as trying to get to sleep as you are contemplating your own mortality. Chances are your heart rate will increase.) 

Rather, it’s more like ...

 ...the intertwining, the interconnections between your physiology and your behavior, the underlying thoughts, emotions, memories,  all of that, and the capacity of each to deeply influence the other under all sorts of circumstances.

First, we ask - what does the behavior look like? Then we ask what went on in that organism a half-second before that behavior occurred to cause it to occur? This is the world of what’s going on with neurons and circuitry, but ...

Just as we are about to get happily settled into that bucket, we push back a bit and say what smell, what sound, what sensory stimulation in the environment caused those neurons to get activated and produce that behavior? 

And then push it one step further behind, to hormone levels in the blood in the last few hours that changed how sensitive you are to those sounds and smells. Then we work our way further back through early development, fetal life, the genetic make-up of an individual, the genetic makeup of an entire population species.

From an endocrinologist’s perspective, Dr Sapolsky goes on to say, Hormone X may explain a behavior. But Hormone X is coded by a gene, so we’re not just talking about endocrinology, anymore -  we’re talking about genetics. And genes are subject to selection, so we’re also talking about evolution. And if we’re talking about sounds and smells and so on - acute triggers for human behavior - by definition we’re also talking about fetal development, which determines how sensitive those systems are to those sorts of stimuli.

Here’s the pathological danger of thinking in buckets. Dr Sapolsky asks us to guess who said this:

Normal psychic life depends upon the good functioning of brain synapses, and mental disorders appear as a result of synaptic derangements. Synaptic adjustments will then modify the corresponding ideas and force them into different channels. Using this approach we obtain cures and improvements but no failures.

The speaker was Egas Moniz, developer of the prefrontal lobotomy, speaking at the occasion of being honored with the Nobel Prize in Medicine in 1949. (Yes, you read that right. No, you are not experiencing psychosis.) Adding our own spin to this, it would be very easy to attribute that statement to any leading psychiatrist bought out by the pharmaceutical industry (which would include just about all of them).

Moniz wasn't an isolated example, Sapolsky informs us. Hence the challenge of breaking out of our buckets.

Dr Sapolsky tells us we have three intellectual challenges. The first is recognizing human circumstances where there is nothing fancy about us whatsoever. “Some of the time we are just a plain old off-the-rack animal.” (Put two female hamsters in a cage, for instance, and their cycles will sync. Put two female humans in a dorm room together, and the same thing happens.)

The second challenge is that although we appear to be just like every animal out there, we do something different with the similarities. For instance, we get stressed by the inevitability of our mortality or by reading something awful that has happened to a child on the other side of the planet.

The flip side of this is we can have compassion and empathy for loved ones and strangers. “It’s the same boring physiology as every other animal out there and we are using it in a way that is unrecognizable.” 

The third challenge is when we are doing something that no other animal out there has anything remotely similar to. For example - a couple comes home, talks, has dinner, talks, goes to bed, has sex, talks, falls asleep. They do this the next day and 30 days running. 

“Hippos would be repulsed by this,” Sapolsky lets us know. "Hardly any animal has nonreproductive sex, let alone day after day, and nobody else talks about it afterward."

The old way of looking at human behavior was by thinking of the brain as an intricate clock with pieces you can take apart and study and then put back together. But it is not as simple as that, Dr Sapolsky informs us. Behavior is more like a cloud, “and you don’t understand rainfall by breaking a cloud down into its component pieces and gluing them back together.”

Dr Sapolsky believes everyone on earth should be forced to learn about behavioral biology. Whether we’re on a jury or voting or wondering about a family member sunk in depression, “we’re behavioral biologists all the time, so it’s probably a good idea we be informed ones.”


Check out Dr Sapolsky’s 57-minute talk on YouTube


Keith said...

The Sapolsky Youtube talk link is dead. It looks like there is a paragraph of text where the URL should be.

I tried to find it with a quick search, but I wasn't sure which talk you had posted before.

John McManamy said...

Many thanks, Keith. I have the link working now. Enjoy the video.

Anonymous said...

These lectures are a treasure:


John McManamy said...

Hey, Anonymous. So glad you're enjoying the lectures. I'm up to lecture #8, and intend on blogging about them in the near future.

buddy2blogger said...

Dr Sapolsky is a great speaker and a great writer. Loved his book 'A Primate's Memoir'.


John McManamy said...

Hey, Buddy. I finished all 25 lectures. Stay tuned for more Sapolsky. Also, thanks for the book recommendation. :)