Anodal transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex improves attentional control in chronically stressed adults

Yong Liu; Qingjin Liu; Jia Zhao; Xuechen Leng; Jinfeng Han; Feng Xia; Yazhi Pang; Hong Chen

doi:10.3389/fnins.2023.1182728

Anodal transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex improves attentional control in chronically stressed adults

Front Neurosci. 2023 Jun 15:17:1182728. doi: 10.3389/fnins.2023.1182728. eCollection 2023.

Authors

Yong Liu^#^{1

2}, Qingjin Liu^#^{1

2}, Jia Zhao^{1

2}, Xuechen Leng^{1

2}, Jinfeng Han^{1

2}, Feng Xia³, Yazhi Pang², Hong Chen^{1

2

4}

Affiliations

¹ Key Laboratory of Cognition and Personality (Ministry of Education), Southwest University, Chongqing, China.
² School of Psychology, Southwest University, Chongqing, China.
³ Department of Hepatobiliary Surgery, Southwest Hospital, Army Medical University, Chongqing, China.
⁴ Faculty of Psychology, Research Center of Psychology and Social Development, Southwest University, Chongqing, China.

^# Contributed equally.

Abstract

Introduction: Chronic stress is a long-term condition that negatively affects cognitive ability and mental health. Individuals who experience chronic stress show poor attentional control. Transcranial direct current stimulation (tDCS) to the dorsolateral prefrontal cortex (DLPFC) modulates executive function domains. Therefore, it is beneficial to investigate whether tDCS of the DLPFC could improve attentional control and relieve stress in chronically stressed individuals.

Methods: We assess the event-related potentials (ERPs) associated with attentional control in individuals with chronic stress after the tDCS intervention. Forty individuals were randomly assigned to either the anodal tDCS group, which received 5 sessions of the 20 min tDCS over the DLPFC (2 mA; n = 20), or the sham tDCS (n = 20). Participants' stress levels, anxiety, depressive symptoms, and state affects were assessed and compared before and after the intervention. The ERP was collected through electroencephalography (EEG) technology during an attentional network test.

Results: After the anodal tDCS, we found a significant decrease in the perceived stress scale (PSS) scores (from an average score of 35.05 to 27.75), p = 0.01 as well as the State-Trait Anxiety Inventory (STAI) scores, p = 0.002. Better performance in the attentional network test, a significant reduction in the N2 amplitudes, and an enhancement in the P3 amplitudes (both cues and targets) were also found in the anodal tDCS group.

Discussion: Our study findings suggest that tDCS to the left DLPFC could effectively relieve chronic stress, potentially reflected by increased attentional control.

Keywords: N2; P3; attentional control; chronic stress; left DLPFC; tDCS.

Grants and funding

The work was supported by the National Natural Science Foundation of China (Nos. 32271087 and 32200849), and the Natural Science Foundation of Chongqing (No. CSTB2022NSCQ-MSX0788).