EEG correlates of cognitive load in a multiple choice reaction task

Area of Science:

• Neuroscience
• Cognitive Psychology
• Electrophysiology

Background:

• Working memory (WM) involves maintaining and manipulating information.
• Cognitive load theory explains how task difficulty affects performance.
• Electroencephalography (EEG) measures brain electrical activity.

Purpose of the Study:

• To investigate EEG correlates of cognitive load during a working memory task.
• To examine the relationship between EEG power changes and task performance.
• To identify sensitive EEG indicators of cognitive load.

Main Methods:

• Twenty-four healthy young adults performed choice reaction tasks with varying numbers of stimulus-response (S-R) mappings.
• EEG data was recorded during low and high cognitive load conditions.
• Performance metrics (e.g., reaction time) and EEG power in different frequency bands (delta, theta, alpha, beta) were analyzed.

Main Results:

• Performance decreased under high cognitive load compared to low load.
• High cognitive load was associated with increased EEG power in delta, theta, and beta bands, and decreased alpha power.
• Alpha power reduction was widespread, while theta and beta power changes correlated with reaction time.

Conclusions:

• EEG alpha and theta power changes are sensitive indicators of cognitive load.
• Reduced alpha power may reflect increased cortical activation for complex WM tasks.
• Increased theta power may indicate enhanced information processing and executive control during demanding tasks.