The Dynamic Properties of a Brain Network During Spatial Working Memory Tasks in College Students With ADHD Traits

Abstract

This study investigated deficits of spatial working memory in college students with attention-deficit/hyperactivity disorder (ADHD) traits using event-related potentials (ERPs) and the spatial 2-back task. We also computed sensory-level activity using EEG data and investigated theta and alpha neural oscillations, phase-locking values (PLV), and brain networks. Based on the scores from the Adult ADHD Self-Report Scale (ASRS) and Conners’ Adult ADHD Rating Scales (CAARS), an ADHD-trait group ( n = 40) and a normal control group ( n = 41) were selected. Participants were required to respond to whether the presented stimulus was at the same location as that presented two trials earlier. The ADHD-trait group showed significantly slower response times than the control group in the spatial 2-back task. In terms of spectrum, the ADHD-trait group showed significantly reduced theta power than the control group. In contrast, the ADHD-trait group exhibited an increased alpha power compared to the control group with the 250–1000 ms interval after stimulus onset. In terms of the PLV, the ADHD-trait group showed significantly weaker theta phase synchrony and fewer connection numbers in frontal-occipital areas than the control group. In terms of the theta brain network, the ADHD-trait group showed a significantly lower clustering coefficient and longer characteristic path length than the control group for the theta band. The present results indicate that college students with ADHD traits have deficits in spatial working memory and that these abnormal activities in neural oscillation, functional connectivity, and the network may contribute to spatial working memory deficits.

Multifractal Functional Connectivity Analysis of Electroencephalogram Reveals Reorganization of Brain Networks in a Visual Pattern Recognition Paradigm

“…To reveal mechanistic background of scale-free coupled dynamics, further clinical trials and animal models are needed using anesthetics, antipsychotics, antiparkinsonian and other medications ( Nasrallah et al, 2017 ). On a final note, a promising field where such visual pattern recognition task could be advantageous is in attention deficit hyperactivity disorder (ADHD) research, where brain network alterations during spatial working memory tasks have already been revealed ( Jang et al, 2020 ).…”

Reduced Power in Fronto-Parietal Theta EEG Linked to Impaired Attention-Sampling in Adult ADHD

“…Amplitude scalp maps in Figure 4 also reflected parietal asymmetry at the N2 ERP, in line with prior findings on N2 ( Gruendler et al, 2011 ). Indeed right-biased cortical asymmetry in ADHD has been a common finding, for example in θ band among adults ( Hale et al, 2014 ; Jang et al, 2020 ). Hale et al (2014) suggested that “atypical rightward asymmetry should be broadly reflective of any form of nonoptimized task-directed brain functioning,” which we elaborate on below.…”

Strength of attention-sampling parietal EEG theta rhythm is linked to impaired inhibition in adult ADHD

“…Asymmetry was also reflected in the amplitude scalp maps in Figure 3, and indeed right-biased cortical asymmmetry in ADHD has been a common finding, for example in theta band among adults (73, 74). Hale et al (73) suggested that “atypical rightward asymmetry should be broadly reflective of any form of non-optimized task-directed brain functioning”, which we elaborate on below.…”

“…Jang et al (74) observed somewhat similar results, with weaker theta and stronger alpha for adults with ADHD traits (self-report only: not clinically screened), performing a spatial 2-back task. They also analysed PLV and found Controls had more significant connections in theta band in the first half of their trials.…”