Low frequency alpha (8-10 Hz) activity correlated with inhibitory behavior

Abstract

Introduction Alpha frequency of EEG and the default mode network (DMN) are predominantly activated during resting-state. Also, alpha frequency power is known to be related with inhibitory function. This study investigated the neuropsychological characteristics of alpha band power and alpha DMN at resting state.

Methods Resting-state EEG, go/nogo ERP/behavioral data, and psychological measures were examined in a total of 101 healthy individuals. Relative alpha (8-12 Hz), low-alpha (8-10Hz), high-alpha (10-12Hz) powers were calculated from the resting-state EEG data. Source activations of 25 DMN regions and their global/nodal network measures (clustering coefficient(CC), path length(PL), efficiency, strength, and eigenvector centrality(EC)) were also calculated. Psychological measures included the Gray's behavioral inhibition/behavioral activation scale (BIS/BAS), the Barratt impulsivity scale (BIS), and the Conner’s adult ADHD rating scale (CAARS). Individuals were divided into 3 groups (low, middle, high) based on the level of power of each total/low/high-alpha frequency band.

Results Significant group differences were found in low-alpha frequency power. The high group had significantly higher BIS score (behavior inhibition), significantly higher levels of global/nodal CC, efficiency, and strength, and a significantly lower PL at all region after Bonferroni correction compared to low and middle group. BIS inhibition was positively correlated with global/nodal CC, efficiency, and strength, and negatively correlated with global PL.

Conclusions Our study revealed that low frequency alpha power is specifically related with inhibitory function. The results also suggest that DMN of low alpha frequency band could be a potential candidate of biological marker of inhibitory function.