Competing hypotheses about neuropsychological mechanisms underlying
psychopathy are seldom examined in the same study. We tested the left
hemisphere activation hypothesis and the response modulation hypothesis of
psychopathy in 172 inmates completing a global–local processing task
under local bias, global bias, and neutral conditions. Consistent with the
left hemisphere activation hypothesis, planned comparisons showed that
psychopathic inmates classified local targets more slowly than
nonpsychopathic inmates in a local bias condition and exhibited a trend
toward similar deficits for global targets in this condition. However,
contrary to the response modulation hypothesis, psychopaths were no slower
to respond to local targets in a global bias condition. Because
psychopathic inmates were not generally slower to respond to local
targets, results are also not consistent with a general left hemisphere
dysfunction account. Correlational analyses also indicated deficits
specific to conditions presenting most targets at the local level
initially. Implications for neuropsychological conceptualizations of
psychopathy are considered. (JINS, 2007, 13,
267–276.)