Neuro-cognitive processes implicated in passive avoidance learning, probabilistic reversal learning and the development of psychopathic tendencies
Chapter 1 introduced psychopathy and evaluated theories attempting to explain this disorder. Experiment 1 assessed passive avoidance learning in children with psychopathic tendencies. Results replicated previous findings with psychopathic adults indicating that this disorder is associated with poor passive avoidance learning. Experiment 2 developed a connectionist model of passive avoidance learning, the output of which was compared with the results obtained in experiment 1. The intact model successfully simulated performance of the comparison children whilst a model impaired in the formation of stimulus- punishment associations most successfully captured the performance of the children with psychopathic tendencies. Experiment 3 assessed the Blood Oxygen Level-Dependent (BOLD) responses associated with passive avoidance learning in healthy adults. Results revealed that successful passive avoidance learning was associated with activation within rostral anterior cingulate cortex, insula, caudate, hippocampus, and the amygdala. Experiment 4 assessed the performance of children with psychopathic tendencies on a novel probabilistic reversal learning paradigm. Results revealed that children with psychopathic tendencies presented with impairment only on the probabilistic contingencies. Further, it was revealed that the children with psychopathic tendencies committed more win-shift errors in the reversal phases. Experiment 5 assessed the performance of adult individuals with psychopathy using a similar task. Results revealed that adults with psychopathy were impaired in both the simple and probabilistic conditions. The adults with psychopathy also committed more win-shift responses in the reversal phases. Experiment 6 assessed the BOLD responses associated with probabilistic reversal learning in healthy adults. Results revealed that errors in both acquisition and reversal phases were associated with activations within dorsomedial and ventrolateral PFC and caudate, and deactivations within medial OFC cortex, amygdala and hippocampus. Chapter 6 re-evaluated the theories of psychopathy in light of the empirical work presented in this thesis, and discussed the implications of these results along with future research directions.