Inconsistent handers show higher psychopathy than consistent handers

Abstract

Three hundred and forty-two university students completed the Short Dark Triad (SD3) and the Edinburgh Handedness Inventory (EHI). Inconsistent handers showed higher psychopathy scores than consistent handers, and no handedness differences were observed for narcissism or Machiavellianism. Participants were further subdivided by quartile into low, moderately low, moderately high, and high psychopathy groups (non-clinical). Absolute EHI scores were equally distributed among low and moderate groups, but were significantly lower for the high psychopathy group. These findings suggest that inconsistent handedness is only associated with the upper quartile of psychopathy scores. Also, males showed significantly higher psychopathy scores than females, and the ratio of male to female inconsistent handers decreased as psychopathy score increased. No gender × handedness interaction indicated that both female and male inconsistent handers have higher psychopathy scores than consistent handers. Although significant, the effects were small and 99.6% of participants were not in the range of a potential clinical diagnosis. The reader, therefore, is strongly cautioned against equating inconsistent handedness with psychopathy.

Fitness costs and benefits associated with hand preference in humans: A large internet study in a Dutch sample

“…Specifically moderate righthanders showed more health-related concerns while at the same time scoring higher on creativity and aggression. This is consistent with several studies reporting that weak hand preference or mixed handedness is associated with somewhat lower performance, psychological disorders and cognitive ability, although these findings are not completely consistent throughout (Corballis et al, 2008;Crow et al, 1998;Nettle, 2003;Nicholls et al, 2010;Papadatou-Pastou & Tomprou, 2015;Rodriguez et al, 2010;Shobe & Desimone, 2016).…”

Is Psychopathy a Mental Disorder or an Adaptation? Evidence From a Meta-Analysis of the Association Between Psychopathy and Handedness

“…Although it was not possible to do so in this study, the degree of handedness would also be an important measure to investigate, particularly because it is more variable than, and confers information independent of, the direction of handedness (Edlin et al, 2015;Prichard et al, 2013). For example, two recent studies using convenience samples have found small, negative correlations between degree of handedness and psychopathy (Shobe & Desimone, 2016;Prichard, 2019), and it would be useful to study this further with larger samples, especially those drawn from populations with higher rates of psychopathy (e.g., clinical and prison populations).…”

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