Primary psychopaths embody the affective
deficits of psychopathy, typically lacking anxiety and fear. Secondary
psychopaths are characterized by the impulsive and aggressive aspects
of psychopathy, and may exhibit heightened anxiety. Lykken (1995) explained
psychopathic heterogeneity using the reinforcement sensitivity
theory (Fowles, 1980; Gray, 1975). The behavioral inhibition system
(BIS) regulates responsiveness to punishment through anxiety, and
may be deficient in primary psychopaths. The behavioral activation system
(BAS) regulates motivation toward reward through impulsivity,
and may be overactive in secondary psychopaths.