Tuesday, September 18, 2007

Some problems from having a human brain

What single emotion has the greatest representation in our cerebral cortex? I believe the answer is fear. I base that on studies of epileptic foci in patients who have an emotional aura to their seizures, whether those seizures stay as simple partial seizures or progress to a more complex or generalized seizure. I learned about those studies over 20 years ago as I went through Elsevier’s multi-volume Handbook of Clinical Neurology preparing for my board exams, which I was happy to pass. In reading since then I haven’t anything as specific in neuroimaging studies, so I believe this old knowledge remains valid.

Fear is also the most common emotional aura for seizures, though if you count confusion as an emotion, you’ll see more confusion among seizure patients post-ictally than fear pre-ictally. Confusion suggests a wide area of dysfunction, though. Fear doesn’t. Many small areas of either temporal lobe can produce fear. The area that does this overlaps with a part of the temporal lobe that produces a pleasant sensation, “contentment” being the best word for it, I think. Fear extends more anteriorly. Contentment extends more posteriorly, with a lot of overlap. Still there is this duality that makes sense with the basic function of our limbic system being whether we should approach or avoid something in our environment.

Our amygdala is wired up to get our attention if there is a behaviorally significant stimulus among our sensations, but it doesn’t determine the specific reason for such attention. Whether a stimulus is something to eat, something to mate with, something to otherwise make mine or something to run away from requires much more of our brain to determine. The fear vs. contentment coming out of our temporal lobes relates to this.

Not all emotions are so localizable. Perhaps fear and contentment are this localized because they are so sensory. Emotions that are more about what action to take as well as some sensation, like anger, are less likely to correspond to a small area of cortex and less likely to be the aura of a seizure.

Still the above knowledge is so much more than the pitiful knowledge we have of the neuroanatomy and neurophysiology of desires, will, imagination, and such. What do we do when we try to think of something, whether imaginary or remembered? It’s hard to say. There’s a lot of neuroscience about how the hippocampus helps to make memories, but what is the physical basis of how we experience long-term memory, including not recalling something when we try, yet it comes to us hours or days later without effort? Anyone can speculate about such things, but actual neuroscience about such aspects of our mind is scarce.

Yet we understand that we are biased. We are biased by emotions. We are biased by having taking shortcuts to thinking that are natural for us to take. We oversimplify, whether by dividing everything into two absolute qualities or by assuming that some simple model we have for a process inside us or out in the world is in fact that simple. We believe the words we use to label an event more than the many possibilities for that event that actually exist. We overgeneralize. We see the faults of others much better than we see faults on our side. We overvalue our own experiences and own beliefs compared to the possibility that others have seen something better than we have.

I understand the difficulty of being emotional. It creates new problems. It stops productive discussion of some issue in order to deal with the emotion. I’ve had occasions to want to be an emotionless automaton. Yet I think the biggest problem with human intelligence isn’t emotions. It’s these cognitive distortions where we think we know much more than we do. We all know when our emotions are tugging at our sleeves, making it hard to be rational. But we don’t know when our thoughts are even more human in their bias than our emotions. Most people speak and write as if they know what they say, yet most people I listen to and read don’t know. It’s not usually because they’re just missing some data. It’s because they’re human, and human beings can be way off in their beliefs.

It’s not just that we’re emotional. It’s not just that we have cognitive distortions. Human beings are often childish, irresponsible in their actions, irresponsible in their beliefs. People cling to their groups, no matter how bad their group might be at thinking. I have a hard time thinking of any strife today where this group bias isn’t a big factor in the strife. People’s desires do indeed conflict over how we should live. Some value selfishness more than others. But the strife over such conflict isn’t just about different desires. Biased beliefs don’t let people even get to the real conflict. The strife winds up being about beliefs, sometimes irrational on both sides.

What is the future course of such human strife? I don’t know. There are many ways that shortcomings of the human brain can be improved. Maybe we’ll be replaced by thinking machines, hopefully more benevolently than in the Matrix or Terminator movies. Maybe we’ll be improved by merging with technology, like the Borg from the later Star Trek stories. Maybe genetic engineering will improve our brains.

I don’t know if any of those are at all likely, but I know how science has helped me with these problems. My emotions sometimes make me want to take shortcuts in how I think of things. I might be willing to jump to conclusions so I can DO SOMETHING. But science has given me many examples of why it’s best to consider all possibilities. When you read about one idea being replaced by another in physics, biology or social science, it makes you consider the possibility of any first idea being wrong.

Cognitive distortions pop up easily, but examples from science have taught me how often something is a spectrum, not black and white, how often a dispute is like whether light is a wave or a particle. The right answer is both, at all times. It’s only human shortcomings that keep anyone from that understanding, even today.

Partisanship pops up even among scientists, yet watching even scientists argue for their side instead of being detached in their analysis doesn’t make me want to be partisans like them. It makes me want to be even more detached, an even better scientist. That’s where the truth is.

Maybe science isn’t enough for most people. Maybe my loyalty to the scientific way of thinking is overdone. Maybe it’s one of those three other solutions to human bias that will dominate our future. Either one of these four possibilities will take over the future or people will decide they’d rather live in strife, a fifth possibility.

I feel like making odds. Maybe I’ll get over that. After all, there’s always another possibility.