Inconsistent handers show higher psychopathy than consistent handers

Area of Science:

• Psychology
• Neuroscience
• Behavioral Science

Background:

• The Dark Triad traits (narcissism, Machiavellianism, psychopathy) are studied in relation to various psychological and behavioral factors.
• Handedness, typically assessed by the Edinburgh Handedness Inventory (EHI), is a well-established indicator of cerebral lateralization.
• Previous research has explored potential links between non-clinical Dark Triad traits and cognitive or neurological variations.

Purpose of the Study:

• To investigate the relationship between handedness consistency and the Dark Triad traits, specifically psychopathy, narcissism, and Machiavellianism.
• To examine gender differences in Dark Triad traits and their association with handedness.
• To determine if inconsistent handedness is associated with specific levels of psychopathy within a non-clinical university student sample.

Main Methods:

• 342 university students completed the Short Dark Triad (SD3) and the Edinburgh Handedness Inventory (EHI).
• Participants were categorized into consistent and inconsistent handers based on EHI scores.
• Psychopathy scores were analyzed across quartiles (low to high) to identify associations with handedness and gender.

Main Results:

• Inconsistent handers reported significantly higher psychopathy scores compared to consistent handers.
• No significant differences in narcissism or Machiavellianism were found based on handedness consistency.
• Higher psychopathy scores were associated with lower absolute EHI scores, particularly in the high psychopathy quartile.
• Males scored higher on psychopathy than females, and the male-to-female ratio of inconsistent handers decreased with increasing psychopathy.

Conclusions:

• Inconsistent handedness is specifically associated with the upper range of non-clinical psychopathy scores, not with narcissism or Machiavellianism.
• While males show higher psychopathy, both genders exhibit higher psychopathy when they are inconsistent handers.
• The observed effects are small, and the vast majority of participants fall within non-clinical ranges, strongly advising against equating inconsistent handedness with psychopathy.