Intelligence and psychopathy: a correlational study on insane female offenders

The occurrence of a significant relationship between psychopathic traits and intelligence is still open to debate. Most of the relevant information has been obtained from crystallized IQ tests or on psychopathic male offenders. In this study we hypothesized a negative correlation between psychopathic traits and fluid intelligence on a sample of criminal female in-patients.

We carried out a correlational study on a selected sample of 56 criminal female offenders. Variables that were measured include the Hare Psychopathy Checklist Revised (PCL-R) total score (and, separately, the scores from its four subscales: Interpersonal, Affective, Lifestyle and Antisocial) and fluid IQ measured by Raven's Progressive Matrices (RPM).

Pearson's correlation between RPM IQ and total PCL-R score was negative (r(54) = -0.55, p < 0.001); women with greater psychopathy traits (total PCL-R score) had lower IQ scores. Negative correlations were also found between IQ and the four PCL-R subscales, Interpersonal, Affective, Lifestyle and Antisocial (r(54) = -0.35, p < 0.01, r(54) = -0.52, p < 0.001, r(54) = -0.53, p < 0.001, and r(54) = -0.49, p < 0.001 respectively).

The results indicate a general negative relationship between PCL-R and IQ, equally distributed across the four subcomponents of the psychopathic trait, and support the view that unsuccessful psychopathic women have poor planning and are unable to foresee and represent future consequences of their actions.