Repetitive TMS over the left dorsolateral prefrontal cortex modulates the error positivity: An ERP study

Area of Science:

• Neuroscience
• Cognitive Psychology
• Brain Stimulation

Background:

• Error processing is crucial for adaptive behavior and goal achievement.
• The dorsolateral prefrontal cortex (DLPFC) role in error processing remains under-investigated.
• Understanding DLPFC's contribution is key to refining models of cognitive control.

Purpose of the Study:

• To investigate the causal role of the left and right dorsolateral prefrontal cortex (DLPFC) in error processing.
• To examine the effects of inhibitory repetitive transcranial magnetic stimulation (rTMS) on electroencephalographic (EEG) signals during error commission.
• To determine if DLPFC stimulation influences specific event-related potential (ERP) components associated with errors.

Main Methods:

• A repetitive transcranial magnetic stimulation (rTMS) protocol was applied to healthy young participants (n=15).
• Inhibitory rTMS (1 Hz for 20 min) was delivered to the left DLPFC, right DLPFC, or Vertex (control site) across three sessions.
• Participants performed a Go/No-Go task immediately after stimulation, while EEG was recorded to analyze event-related potentials (ERPs).

Main Results:

• No significant behavioral changes were observed following rTMS.
• Stimulation of the left DLPFC led to a reduction in the amplitude of the error positivity (Pe) component of ERPs.
• The error-related negativity (ERN) component was not affected by left or right DLPFC stimulation.

Conclusions:

• The left DLPFC plays a role in later stages of error processing, specifically influencing error awareness.
• rTMS is a viable tool for investigating the causal contribution of specific brain regions to cognitive processes like error detection.
• Findings suggest a dissociation in the temporal dynamics of error processing within prefrontal cortex regions.