Extraversion and behavioural approach system in stimulus analysis and motor response initiation

Area of Science:

• Cognitive Neuroscience
• Personality Psychology
• Psychophysiology

Background:

• Previous research suggests extraversion influences sensorimotor processing speed.
• The revised Reinforcement Sensitivity Theory (rRST) provides a framework to explore personality traits beyond extraversion.
• Understanding the neural underpinnings of personality-related processing speed differences is crucial.

Purpose of the Study:

• To validate extraversion's effect on sensorimotor processing speed.
• To extend these findings to the sub-traits of the Behavioural Approach System (BAS) within the rRST framework.
• To investigate the relationship between BAS facets, BIS, FFFS, and electrophysiological measures of processing speed.

Main Methods:

• Assessed extraversion, BAS facets (BAS-GDP, BAS-RI, BAS-RR, BAS-I), BIS, and FFFS in 51 volunteers.
• Recorded electrophysiological measures including S-LRP, R-LRP, S-EMG, R-EMG, and P3 ERP components.
• Participants performed a two-choice Go/NoGo visual discrimination task with varying difficulty.

Main Results:

• Higher extraversion and BAS Reward Interest (BAS-RI) were associated with shorter S-LRP and EMG latencies.
• Higher Impulsivity (BAS-I) correlated with shorter R-RLP latency on difficult tasks.
• Higher Fight-Flight-Freeze System (FFFS) levels linked to longer S-LRP and S-EMG latencies; higher BIS linked to better accuracy.
• Extraverts and individuals high on BAS-RR and BAS-I showed smaller P3 amplitudes.

Conclusions:

• Faster cortical premotor initiation in high extraverts, BAS-RI, and low FFFS individuals may explain their faster motor responses.
• Smaller P3 amplitudes in extraverts, BAS-RR, and BAS-I individuals might suggest reduced perceptual processing capacity.
• This study extends the understanding of personality's influence on sensorimotor processing speed and its neural correlates.