Journal article
Personalized beta band HD-tACS over the left SMA improves speech and limb movement by modulating prefrontal delta oscillations in neurotypical young adults
Journal of neural engineering, Vol.22(5), 056011
10/01/2025
DOI: 10.1088/1741-2552/ae00f5
PMID: 40882669
Abstract
The supplementary motor area (SMA) demonstrates abnormal beta activity (13-30 Hz) during speech and limb movement tasks in neurological conditions such as Parkinson's disease (PD). Transcranial Alternating Current Stimulation (tACS) has demonstrated promising improvements in motor and non-motor functions by entraining endogenous neural oscillations. We conducted an exploratory study on the modulatory effects of personalized beta high-definition (HD)-tACS over the left SMA on speech production and limb movement.
In a repeated-measures experiment, 22 neurotypical young adults were recruited to participate in four stimulation conditions: sham, High-Definition Transcranial Random Noise Stimulation (HD-tRNS), and HD-tACS tuned to each individual's frequency of maximal SMA beta activity (identified using source-localized EEG) during speech (tuned-to-speech; TtS) and limb movement (tuned-to-limb; TtL). All participants completed a 25-minute sham/active stimulation over the left SMA, followed by an interleaved speech production and limb movement task.
Behavioral results showed that active stimulation resulted in more pronounced improvements in reaction times compared to the sham condition, regardless of the active stimulation type. The neural correlates of this aftereffect were indicated by a prominent modulation of delta power in prefrontal and frontocentral electrodes during speech and limb movement tasks following personalized beta TtS and TtL HD-tACS, relative to sham and tRNS.
Personalized beta HD-tACS modulated delta oscillations, instead of beta rhythms, in a task-specific manner, highlighting the brain's adaptive response. These findings have implications for neurological conditions such as PD, which are characterized by deficits in speech production and limb motor coordination.
Details
- Title: Subtitle
- Personalized beta band HD-tACS over the left SMA improves speech and limb movement by modulating prefrontal delta oscillations in neurotypical young adults
- Creators
- Fatemeh Tabari - Louisiana State UniversityJoel Isaac Berger - University of Iowa Hospitals and ClinicsMelda Kunduk - Louisiana State UniversityArend W A Van Gemmert - Louisiana State UniversityKarim Johari - Louisiana State University
- Resource Type
- Journal article
- Publication Details
- Journal of neural engineering, Vol.22(5), 056011
- DOI
- 10.1088/1741-2552/ae00f5
- PMID
- 40882669
- NLM abbreviation
- J Neural Eng
- ISSN
- 1741-2560
- eISSN
- 1741-2552
- Publisher
- IOP Publishing Ltd
- Grant note
- Louisiana Board of Regent Research Competitiveness Program
This study is financially supported by the Grant from Louisiana Board of Regent Research Competitiveness Program (Award Number: AWD-004500).
- Language
- English
- Electronic publication date
- 08/29/2025
- Date published
- 10/01/2025
- Academic Unit
- Neurosurgery
- Record Identifier
- 9984958289602771
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