Differential EEG Characteristics during Working Memory Encoding and Re-encoding

TL;DR

This study investigates EEG differences during working memory encoding and re-encoding, revealing distinct neural patterns that could enhance learning efficiency understanding.

Contribution

It provides new insights into neural activity differences between encoding and re-encoding phases using spectral and phase-locking analyses.

Findings

Alpha PSD decreases with learning progression

Theta, beta, and gamma PLV differ across brain regions

Significant differences in phase-amplitude coupling between phases

Abstract

Many studies have discussed the difference in brain activity related to encoding and retrieval of working memory (WM) tasks. However, it remains unclear if there is a change in brain activation associated with re-encoding. The main objective of this study was to compare different brain states (rest, encoding, and re-encoding) during the WM task. We recorded brain activity from thirty-seven participants using an electroencephalogram and calculated power spectral density (PSD) and phase-locking value (PLV) for different frequencies. In addition, the difference in phase-amplitude coupling (PAC) between encoding and re-encoding was investigated. Our results showed that alpha PSD decreased as the learning progressed, and theta PLV, beta PLV, and gamma PLV showed differences between brain regions. Also, there was a statistically significant difference in PAC. These findings suggest the possibility of improving the efficiency of learning during re-encoding by understanding the differences in neural correlation related to learning.