Hemispheric asymmetry in the processing of an emotional working memory task

Area of Science:

• Cognitive Neuroscience
• Neuroimaging
• Psychology

Background:

• Emotion and working memory are crucial daily functions.
• Existing research links emotion and working memory, but neural mechanisms are unclear.

Purpose of the Study:

• Investigate how emotional valence (negative, positive, neutral) affects working memory performance.
• Examine the neural response during a working memory task using emotionally valenced images.

Main Methods:

• 32 participants completed a 2-back task using negative, positive, and neutral images from the International Affective Pictures System (IAPS).
• Electroencephalography (EEG) was used to measure neural responses, including event-related potentials (ERPs) and theta power.
• Repeated-measures ANOVA analyzed differences in performance, response time, and neural activity across hemispheres and valence conditions.

Main Results:

• No significant differences in working memory task performance or response time were observed based on image valence.
• Increased right-hemisphere activity was detected for the P3 component amplitude and time-locked theta power across all image valences.
• The right-hemisphere P3 component showed significantly greater mean amplitude for negative images compared to neutral and positive images.

Conclusions:

• The right hemisphere plays a dominant role in processing both working memory and emotional information.
• Negative emotional images elicit greater neural resource allocation in the right hemisphere, supporting working memory task performance.
• These findings elucidate the neural underpinnings of the emotion-working memory interaction.