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Saturday, July 02, 2005

Stress and the Hungry Dinosaur

Evolutionary Psychology: 
the phrenology of the 21st century

...or Stress and the Hungry Dinosaur
First, a mind experiment.
Choose a sex symbol from the options below :
Ok. Now assume that your sex symbol actually knows about you and wants to meet you.

Now think about how you'd react.
Now, assume that your sex symbol not only wants to meet you but wants to date you.
Again, think about how you'd react.
Now, assume that your sex symbol not only wants to meet you, but also wants to share bodily fluids and DNA with you.
Again, think about how you'd react.
Assuming that you are a normal homo sapiens, or even an abnormal one, you can presume that you would express a feeling of mild interest to sexual arousal depending upon what you anticipate your relationship to your sex symbol will be. However, as our reactions escalate, they also change in kindas different biochemical, neurological, and physical reactions begin to kick in. 
Of course, common sense and shared experience tells us that for sex, an initial interest or anticipation does not represent a scaled down or 'lite' version of a full blown state of sexual arousal, since arousal represents physiological reactions that differ in type as well as in scale. Different reactions simply come about with different information, and one type of reaction does not occur to fit all.
Now lets assume that you are a harried office worker. A day at the office may confront you with numerious tasks that have to be performed in certain ways and within certain times. Let's say that you have to do some office project before a 5pm deadline. If the deadline is missed, then you may have to postpone finishing the job until tomorrow, but the results may be merely inconvenience, a reprimand from your boss, or a gun to your head (particularly if you are an Iraqi office worker). As the results scale upwards in severity, different physiological changes also occur that are different in scale but also different in kind. Whereas inconvenience mainly gets us tense, a gun to our heads makes us panic or fearful as well as tense. Yet we would hardly call a daily inconvenience a mild version of panic, because we know that tension and fear are entirely different things. 
Obvious facts such as these have unfortunately not sunk in with psychologists, who are fond of lumping different behaviors and their different causes under every more convoluted classification schemes that beg the question of explaining behavior under the pretense of simplifying it. Thus, if you are anxious, hungry, lonely, or just plain lusty, just push all their respective manifestations into a mental module, syndrome, disease, impulse, or trait, and then you can forget about explaining it, since its cause is hardwired invisibly deep in the human brain. This devolves psychology into a sort of bug hunt, where psychologists endlessly obsess about how to categorize and pin down all human behavior under a periodic table that changes with the merest fancy. 
In ancient times behavior was due to a catalog of evil spirits, vapors, or weird physical manifestations like wandering uteri. (The Latin name for this, or hysteria, literally means wandering uterus, really!) In the last century, the 'science' of phrenology made behavior literally reflected in the bumps on your head, although thankfully nowadays you need a bump on your head to believe such tripe. But not to be undone, modern man has made simple minded thinking almost respectable with the introduction of evolutionary psychology, which has come to think of it resurrected phrenology all over again.  
The Brain according to Phrenology
The Brain According to Evolutionary Psychology
Stress and those Hungry Dinos

Consider as a case in point the concept of stress. Go to any source on stress, from a textbook to the world wide web, and you'll doubtless hear the tiresome cliche about stress being due to some hardwired propensity to panic due to our ancestors constant need to run away from prehistoric beasts. This was a tough time for our ancestors, having to constantly run from dinosaurs and run after buxom cave babes who made matters all the more stressful by wearing skimpy animal skins,and being cornered on mountain ledges by hungry pterodoctyls. It was a savage world whose only law was lust, as THIS WAS THE WAY IT WAS!
Evolutionary Psychology: a Modern Day  Phrenology
According to 19th Century phrenology, different parts of the brain were responsible for different character traits or faculties, and if you had for example a particularly large 'hope' module in your brain, that large faculty would correspond to an equally large lump on your head. Thus, a personality could be read by simply noting the shape of one's noggin. This of course was sheer nonsense, although it didn't seem so to the wise psychological minds of the time. However, even stupidity has to yield to the facts, as neuroscience demonstrated that reading bumps is a fairy story told by bumpkins.
But have we modern minds escaped such foolishness? Not apparently, as evolutionary psychology has risen to the challenge by hypothesizing similar brain modules or faculties, but this time by deducing how they must be by guessing how our ancestors had to be. In other words, if we uniformly chase women and get stressed when chased by beasts or encounter a bestial day at the office, then there must be a mental module shaped by evolution that makes it so. And how do you prove it? Simple, you fabricate a 'just so' story that postulates that the evolutionary pressures our ancestors faced were just so.  
Enter Ethology

Like phrenologists of old, evolutionary psychologists merrily hypothesize hypothetical faculties with abandon, which are easily revealed by the bumps our ancestors had to take while evolving rather then observing actual bumps on their head. But if we look how our brains are actually put together, and how brain processes create behavior in all creatures, the evolutionary explanations can take an entirely different form from this ethologicalperspective. To understand this, its important to understand the humble mouse, and our humble mouse like ancestor.
The problem our ancient ancestors faced, as well as every crawling. swimming, and flying thing then and now, is how you can go about doing things and choosing to do things if you don't have much of a brain. We modern homo-sapiens have a lot of gray matter, or a large cerebral or neo-cortex that allows us to think things out and make informed choices. But a mouse doesn't have much gray matter, and our ancient ancestor,  a hairy three inch shrew, didn't have much either. But do primitive animals need gray matter to navigate their worlds? Surprisingly, the answer is no. Remove what little neo-cortex a mouse has, and he will still act pretty much like a mouse. So, in lieu of all that 'thinking' matter, how does the little critter go about well, thinking? The obvious answer is that he had to use what he's got, namely the feedback mechanisms that are imbedded in his primitive brain and body. These of course are the hardwired instinctive behaviors from sex to foraging to 'fight or flight' that are the end result of sensory events (e.g. sight of a predator, a food source, or a receptive female) that signal tiny organelles (e.g. hypothalamus, amygdala) deep in the brain. But when the mouse or shrew is approaching a mate, foraging for food, or escaping a predator, it still must receive feedback from somatic or bodily events such as its muscles that tell it where it is and where its going. If it has to choose between two options of similar value,
Adam and Eeek: Hairy Three Inch Shrew
Accurate Evolutionary Depiction of Caveman Times
So that's why we are hard wired to get stressed out. Whether we are reacting to a crying child or a screaming boss, its all because of  evolved traits due to all those hungry dinos.
such as what fork in the road to take, it must rely on its gut impulses because its gut is almost literally all it has to go on. This concept, called the 'somatic marker', reflects a reliance on somatic events to mark or signal the value of making a decision in one direction or another. Thus muscular tension did not just occur to prime an animal to escape from a predator, but also occured to mediate choices between events that were anything but threatening. So, for our mammalian ancestors, tension did not just occur as part of a 'flight or fight' response, but also because it enabled them to make decisions or 'think' effectively.
This lesson from ethology demonstrates that a similar response, namely muscular tension, may occur for wholly different reasons and mediate entirely different ends. Thus tension may occur to prime an escape from a threatening situation, or it may occur to mediate choice. Applied to our modern world, a harried office worker will more likely become tense not because he is confronting too many threats, but too many choices. Hence, the rationale that our tensions occur solely as some remnant of our ancestors' need to incessantly run away from prehistoric beasts is oversimplified, and wrong.
By understanding the ethological rules of behavior, we can more precisely deduce the evolutionary pressures that selected the bodily processes that embody those rules. Ignore ethology, and human nature becomes an over simplified cartoon of hard wired cavemen running after hard bodied cave babes. Such a simplistic view also unfortunately limits the procedures that you can deduce to change behavior, and in particular of stress. That is the subject of part two of this paper.

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