Instrumental Learning and Relearning in Individuals with Psychopathy and in Patients with Lesions Involving the Amygdala or Orbitofrontal Cortex

Previous work has shown that individuals with psychopathy are impaired on some forms of associative learning, particularly stimulus-reinforcement learning ( Blair et al., 2004 ; Newman & Kosson, 1986 ). Animal work suggests that the acquisition of stimulus-reinforcement associations requires the amygdala ( Baxter & Murray, 2002 ). Individuals with psychopathy also show impoverished reversal learning ( Mitchell, Colledge, Leonard, & Blair, 2002 ). Reversal learning is supported by the ventrolateral and orbitofrontal cortex ( Rolls, 2004 ). In this paper we present experiments investigating stimulus-reinforcement learning and relearning in patients with lesions of the orbitofrontal cortex or amygdala, and individuals with developmental psychopathy without known trauma. The results are interpreted with reference to current neurocognitive models of stimulus-reinforcement learning, relearning, and developmental psychopathy.