Neural changes to transcranial alternating current stimulation in the gamma range over the left frontoparietal network: a preliminary eLORETA EEG study

Abstract

Applying transcranial alternating current stimulation (tACS) at 40 Hz to the frontal and parietal regions can improve cognitive dysfunctions. This study aimed to explore the neural changes following transcranial electrical stimulation treatment. Electroencephalography (EEG) recordings were obtained from a cohort of 34 participants with various cognitive impairments before and after 12 sessions of tACS treatment. Alternating currents at 2.0 mA were administered to the electrode positions F3 and P3 for 20 minutes of each session, following the 10-20 EEG convention. Using eLORETA, scalp-recorded signals were reconstructed into cortical current source density (CSD). We then assessed the differences in power and connectivity strength across multiple spectra (delta to gamma). We observed a consistent trend of decreased CSD at the stimulating sites across different spectra, most prominent at beta and gamma bands (P < 0.01). On the contrary, the right hemisphere showed a trend of increased CSD, which was likely mediated by inter-hemispheric rivalry. In addition, the connectivity strength between the left frontal and parietal regions increased significantly (P = 0.017). Artificial injections of tACS would de-synchronize regional oscillation and enhance inter-regional crosstalk. The pattern of neural changes was concordant with our previous tACS reports (5-Hz), suggesting common neural mechanisms driving the neurophysiological effects of tACS.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

This study did not receive any funding

Author Declarations

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Pearl IRB wavied ethical approval for this work (approval number 2023-0133).

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

Data Availability

All data produced in the present study are available upon reasonable request to the authors

留言 (0)

沒有登入
gif