Preparation for action: an ERP study about two tasks provoking variability in response speed

Area of Science:

• Cognitive Neuroscience
• Psychophysiology

Background:

• Response preparation and execution are fundamental cognitive processes.
• Event-related potentials (ERPs), such as P3 and contingent negative variation (CNV), provide neural correlates of cognitive functions.
• Individual differences in response speed and associated neural activity are not fully understood.

Purpose of the Study:

• To examine the covariation between response speed and ERPs during response preparation.
• To determine if these variations can be experimentally controlled.
• To investigate the role of attentional strategies in inter- and intraindividual differences in performance and ERPs.

Main Methods:

• Two S1-S2 choice response tasks with temporal uncertainty were employed.
• Experiment 1: S1 (cue) was 100% informative.
• Experiment 2: S1 was 50% uninformative, with an attention-grabbing visual display.

Main Results:

• Fast subjects exhibited larger P3 amplitudes in Experiment 1.
• Terminal CNV (tCNV) positively covaried with response speed within individuals.
• Interindividual differences in ERPs and response time distributions disappeared in Experiment 2, suggesting strategy shifts.

Conclusions:

• Group differences in Experiment 1 likely stemmed from varying visual attention allocation strategies.
• Interindividual strategy variations produced different effects compared to intraindividual efficiency variations.
• Task demands and information processing influence both behavioral and neural responses.