Rats behave as if they have the capacity for being fearful, surprised, or sexually aroused. There is little evidence, however, to suggest that they experience any of the emotions we call pride, sadness, joy, anxiety, guilt, shame, anger, jealousy, disgust, love, or moral outrage. These two uses suggest there are several fear states, each with its own genetics, incentives, physiological patterns, and behavioral profiles. These related states of fear should be distinguished from states of anxiety, in which future aversive events are anticipated. For two decades I have been involved in studying a large group of children from whom we have learned that different combinations of temperament and life history can produce an excessively fearful or anxious adolescent or adult.
Different fears demand different therapeutic interventions.
Some children in this subset go on to develop a profile that closely resembles social phobia in adolescence. When stimulated, twenty percent of the infants responded with agitated limb movement, muscle spasticity, and occasional arching of the back, accompanied by fretting and crying. About 35 to 40 percent of the 450 children showed little motor activity and no distress in response to the same stimuli. We believe the low reactive children inherited an amygdala with a high threshold of excitability due to a different neurochemistry in the amygdala. Both groups of children were observed at various intervals.