Posted 5/2/12 on The Doctor Weighs In
We all know the feeling; we experience something terribly unpleasant, such as loss in of a friend or a family member, betrayal by a spouse or a close friend, significant loss of money. Are your senses as sharp as normal, or are you distracted, having difficulty analyzing situations and making decisions?
You are not alone. Even animals show what on the surface seems to be poor decision-making. Shock an animal with an electric current and it will tend to cower in a corner, trying to avoid not only a repeat of the shock, but any potentially negative stimulus. This kind of behavior is not maladptive. In fact, it is adaptive. How so? Because in a dangerous environment there is no time for the brain to analyze situations and judge their degree of risk. The animal that reacts defensively and fast will survive. The one that lingers to assess the situation is likely to perish.
All this makes sense, but how is not-thinking-clearly related to that? Through the brainactively altering the balance between the emotional and rational parts of the decision-making process. In anatomical terms, the amygdala, the structures deep in the midbrain that coordinate emotions such as fear and rage, become very active; on the other hand, structures that involve analytical thinking, such as the prefrontal cortex, show diminished activity. Better fearful than sorry.
Being distracted when experiencing loss implies perceptual impairment. You are less likely to hear the birds sing or listen intently to a Beethoven sonata when you just lost your house to foreclosure and the sheriff threw you out on the street. How is that adaptive?
It isn’t. This is an example of how our behavior is shaped by its deep evolutionary roots, although the environmental circustances have radically changed.
Loss and perceptual impairment.
A paper published in the Journal of Neuroscience (Monetary Loss Alters Perceptual hresholds and Compromises Future Decisions via Amygdala and Prefrontal Networks) by Offir Laufer and Rony Paz, of the Dept. of Neurobiology at the Weitzmann Institute in Israel, studied the effect of monetary loss on sensory loss. Note the difference: not on decision-making (we know it’s impaired) but on our reduced sensitivity to the environment. For a test of sensory loss they picked the threshold of hearing a pure tone. Audiometer hearing test is administered to a person sitting in a soundproof booth wearing a set of headphones which is connected to an audiometer. Small foam insert earphones placed in the ears may also be used. The audiometer produces tones at specific frequencies and set volume levels to each ear independently. The audiologist plots the loudness, in decibels, on an audiogram. People having their hearing tested will convey that they have heard the tone by either raising a hand or pressing a button.
They found that (monetary) loss conditioning, when compared with neutral exposure (namely, no loss), decreases sensitivity and increases perceptual thresholds (i.e., a relative increase in the just-noticeable-difference). What about gain rather than loss? Loss caused perceptual impairment, gain did not. What this implies is that loss of any kind has what psychologists callnegative valence, meaning that it has an intrinsic aversiveness. They also showed that these perceptual changes resulted in overall increased and irrational monetary loss for the subjects. They used functional imaging (fMRI) to identify the neural network whose activity correlated with the deterioration in sensitivity on an individual basis. They found that both the prefrontal cortex, where rational decisions are made, and the activity in the amygdala, where fear and anger are generated, were tightly correlated with the loss of perceptual sensitivity and to making wrong decisions.
Originally the generalized reaction of fear (the amygdala overwhelming the analytical prefrontal cortex) had an adaptive value. In today’s environment the same neurological reaction has become maladaptive. Hence the empirical experience to never react when we are angry, never make decisions under duress. This wisdom has developed to compensate for the way our brain was designed.