Effect of working memory on evaluation-related frontocentral negativity

Area of Science:

• Neuroscience
• Cognitive Psychology
• Electrophysiology

Background:

• A negative event-related potential (ERP) component is observed after both correct and error responses.
• This component is widely believed to originate in the anterior cingulate cortex (ACC).
• The role of working memory in the processes underlying this ERP component remains largely unexplored.

Purpose of the Study:

• To investigate the impact of working memory load on the evaluation process reflected by the post-response negative ERP component.
• To determine if the anterior cingulate cortex (ACC) activity associated with this ERP is modulated by working memory demands.

Main Methods:

• Utilized a modified continuous performance task (CPT) with varying cue-stimulus delays to manipulate working memory load.
• Employed conventional ERP averaging techniques for signal analysis.
• Applied low-resolution brain electromagnetic tomography (LORETA) for source localization of the ERP component.

Main Results:

• A significant effect of working memory delay on the amplitude of the post-response negative ERP component was identified.
• Source localization confirmed the origin of this component in the ACC.
• The precise location within the ACC varied depending on the level of working memory demand.

Conclusions:

• The findings support the existence of a general response evaluation system reflected by the post-response negative ERP component.
• The modulation of this ERP component by working memory suggests a functional connection between the medial frontal cortex (including ACC) and lateral frontal regions crucial for working memory.
• This study highlights the interplay between cognitive control, response monitoring, and working memory processes within frontal brain networks.