ABSTRACT
Behavioral inhibition reflects both reflexive and automatic responses and nonreflexive and less automatic responses. This chapter discusses several different forms of behavioral inhibition, suggesting that central dopamine plays an important role. Subcortical structures, such as the amygdala, are also linked to behavioral inhibition and social wariness. Excessive shyness, or behavioral inhibition in social situations in young children who also had greater cortisol levels, has been shown to lend itself to greater activation of the amygdala when these same subjects were tested later in life. Children born with phenylketonuria, a metabolic disorder due to a genetic defect, have a disruption in the normal balance of amino acids, a balance which is necessary for the production of adequate amounts of dopamine. These children show impairments in diverse forms of behavioral inhibition. Children with hyperactive disorder exhibit a broad array of behavioral symptoms and compromised cognitive functions in multiple settings.
