This study evaluated the relation between five-factor model (FFM) personality traits and intra-individual variability (IIV) in executive functioning (EF) using both subjective self-report and objectives measures of EF.

165 university participants (M=19 years old, SD=1.3; 55.2% White, 35.2% African American, 72.7% female) completed the Barkley Deficits in Executive Functioning Scale-Long Form (BDEFS), IPIP-NEO Personality Inventory, Trail-Making Test (TMT) Parts A and B, and the Neuropsychological Assessment Battery (NAB) EF module. A participant’s IIV was calculated as the standard deviation around their own mean performance. Objective EF IIV was computed from T-scores for performance on Trails A, Trails B, and the NAB EF module. Subjective EF IIV was computed from T-scores for performance across BDEFS domains.

Pearson r correlations were used to evaluate the relation between subjective and objective IIV and FFM traits of personality. Subjective EF IIV was positively correlated with FFM neuroticism [r=.48; p<.001] and negatively correlated with FFM conscientiousness [r=-.43; p<.001], extraversion [r=-.18; p=.023] and agreeableness [r=-.22; p=.004]. There were no significant associations between FFM traits and objective EF IIV performance. There was additionally no significant relation between subjective EF IIV performance and objective EF IIV.

Personality traits were associated with individual variability on a self-reported measure of EF but not on performance-based EF measures. These results suggest that IIV for the BDEFS was influenced by personality traits, particularly neuroticism and conscientiousness, and may reflect method variance. It was notable that IIV was not correlated between subjective and objective EF measures.