EEG correlates of working memory performance in females

Boris Kotchoubey,Yuri G Pavlov

doi:10.1186/s12868-017-0344-5

Boris Kotchoubey, Yuri G Pavlov

Open Access

https://doi.org/10.1186/s12868-017-0344-5

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Journal: BMC Neuroscience	Publication Date: Feb 13, 2017
Citations: 42	License type: open-access

Affiliation: University of Tübingen, Ural Federal University

Abstract

BackgroundThe study investigates oscillatory brain activity during working memory (WM) tasks. The tasks employed varied in two dimensions. First, they differed in complexity from average to highly demanding. Second, we used two types of tasks, which required either only retention of stimulus set or retention and manipulation of the content. We expected to reveal EEG correlates of temporary storage and central executive components of WM and to assess their contribution to individual differences.ResultsGenerally, as compared with the retention condition, manipulation of stimuli in WM was associated with distributed suppression of alpha1 activity and with the increase of the midline theta activity. Load and task dependent decrement of beta1 power was found during task performance. Beta2 power increased with the increasing WM load and did not significantly depend on the type of the task. At the level of individual differences, we found that the high performance (HP) group was characterized by higher alpha rhythm power. The HP group demonstrated task-related increment of theta power in the left anterior area and a gradual increase of theta power at midline area. In contrast, the low performance (LP) group exhibited a drop of theta power in the most challenging condition. HP group was also characterized by stronger desynchronization of beta1 rhythm over the left posterior area in the manipulation condition. In this condition, beta2 power increased in the HP group over anterior areas, but in the LP group over posterior areas.ConclusionsWM performance is accompanied by changes in EEG in a broad frequency range from theta to higher beta bands. The most pronounced differences in oscillatory activity between individuals with high and low WM performance can be observed in the most challenging WM task.

Highlights

The study investigates oscillatory brain activity during working memory (WM) tasks
A number of neuroimaging studies demonstrated that maintenance of information in WM engages a broad network of neural structures mostly including prefrontal cortex, parietal and temporal areas [2, 7]
The differences were less pronounced in the comparison between 6 and 7 letters in the alphabetical order (p = 0.011; not significant after Bonferroni correction)

Summary

Introduction

The study investigates oscillatory brain activity during working memory (WM) tasks. The tasks employed varied in two dimensions. We expected to reveal EEG correlates of temporary storage and central executive components of WM and to assess their contribution to individual differences. One of them is responsible for temporary storage of information in modality-specific buffers. Another key component, the central executive, is considered to be a set of tools designed to maintain the active. A number of neuroimaging studies demonstrated that maintenance of information in WM engages a broad network of neural structures mostly including prefrontal cortex, parietal and temporal areas [2, 7]. Existing research highlights the importance of the fronto-parietal network activation in working memory processes, especially in high demanding tasks [9,10,11,12,13]. Individual differences in working memory capacity are determined by fronto-parietal white matter connectivity [14]

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