There is mixed evidence for a relationship between impulsivity and executive functions. Although impulsivity is heterogeneous, previous research did not examine partial relationships controlling for shared variance across sub-traits to evaluate the specificity of these associations. Eighty-five undergraduates completed the Barratt Impulsiveness Scale-11 (BIS-11) and the AX-expectancy version of the Continuous Performance Task (AX-CPT). This task engenders a conflict between two response tendencies by manipulating the frequency of specific trial types. We conducted mixed model analyses to determine the unique variance in behavioral and electrophysiological indices of relevant cognitive functions accounted for by the facets of BIS-11. Motor Impulsiveness was associated with smaller P3 across sites and conditions suggesting a general cognitive limitation not specific to the condition requiring the most inhibition, and larger N2 in some conditions indicating heightened conflict detection. Non-Planning Impulsiveness was related to smaller N2 when inhibiting a primed response and with greater P3 in some contexts. Attentional Impulsiveness appeared to be associated with an inefficient conflict detection system indicated by relatively normal engagement in trials involving the non-potent response, but relatively over engagement in the prepotent condition. Our findings suggest that sub-traits of impulsivity are differentially related to executive processes.
- N2 amplitude
- P3 amplitude