In the brain, these thoughts can often be traced to overreactivity in the amygdala, a small site in the middle of the brain that, among its many other functions, responds to novelty and threat. When the amygdala works as it should, it orchestrates a physiological response to changes in the environment. That response includes heightened memory for emotional experiences and the familiar chest pounding of fight or flight. But in people born with a particular brain circuitry, the kind seen in Kagan’s high-reactive study subjects, the amygdala is hyperreactive, prickly as a haywire motion-detector light that turns on when nothing’s moving but the rain. Other physiological changes exist in children with this temperament, many of them also related to hyperreactivity in the amygdala. They have a tendency to more activity in the right hemisphere, the half of the brain associated with negative mood and anxiety; greater increases in heart rate and pupil dilation in response to stress; and on occasion higher levels of the stress hormones cortisol and norepinephrine.
Todd Suomela on 26 Aug 08Trivial reminders of money made a surprisingly large difference. For example, where the control group would offer to spend an average of 42 minutes helping someone with a task, those primed to think about money offered only 25 minutes. Similarly, when someone pretending to be another participant in the experiment asked for help, the money group spent only half as much time helping her. When asked to make a donation from their earnings, the money group gave just a little over half as much as the control group. Why does money makes us less willing to seek or give help, or even to sit close to others? Vohs and her colleagues suggest that as societies began to use money, the necessity of relying on family and friends diminished, and people were able to become more self-sufficient. "In this way," they conclude, "money enhanced individualism but diminished communal motivations, an effect that is still apparent in people's responses today."
