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Review
. 2023 May-Jun;16(3):748-755.
doi: 10.1016/j.brs.2023.04.001. Epub 2023 Apr 5.

The impact of gamma transcranial alternating current stimulation (tACS) on cognitive and memory processes in patients with mild cognitive impairment or Alzheimer's disease: A literature review

N R Nissim  1 , D V H Pham  2 , T Poddar  2 , E Blutt  2 , R H Hamilton  3
Affiliations
Review

The impact of gamma transcranial alternating current stimulation (tACS) on cognitive and memory processes in patients with mild cognitive impairment or Alzheimer's disease: A literature review

N R Nissim et al. Brain Stimul. 2023 May-Jun.

Abstract

Background: Transcranial alternating current stimulation (tACS)-a noninvasive brain stimulation technique that modulates cortical oscillations through entrainment-has been demonstrated to alter oscillatory activity and enhance cognition in healthy adults. TACS is being explored as a tool to improve cognition and memory in patient populations with mild cognitive impairment (MCI) and Alzheimer's disease (AD).

Objective: To review the growing body of literature and current findings obtained from the application of tACS in patients with MCI or AD, highlighting the effects of gamma tACS on brain function, memory, and cognition. Evidence on the use of brain stimulation in animal models of AD is also discussed. Important parameters of stimulation are underscored for consideration in protocols that aim to apply tACS as a therapeutic tool in patients with MCI/AD.

Findings: The application of gamma tACS has shown promising results in the improvement of cognitive and memory processes that are impacted in patients with MCI/AD. These data demonstrate the potential for tACS as an interventional stand-alone tool or alongside pharmacological and/or other behavioral interventions in MCI/AD.

Conclusions: While the use of tACS in MCI/AD has evidenced encouraging results, the effects of this stimulation technique on brain function and pathophysiology in MCI/AD remains to be fully determined. This review explores the literature and highlights the need for continued research on tACS as a tool to alter the course of the disease by reinstating oscillatory activity, improving cognitive and memory processing, delaying disease progression, and remediating cognitive abilities in patients with MCI/AD.

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Conflict of interest statement

Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

Fig. 1.
Fig. 1.
Summary of articles exploring gamma stimulation in animal models of AD and tACS in aging and MCI/AD patients.
See this image and copyright information in PMC

References

    1. Farias ST, Mungas D, Reed BR, Harvey D, Decarli C. Progression of mild cognitive impairment to dementia in clinic-vs community-based cohorts. Arch Neurol 2009;66:1151–7. 10.1001/archneurol.2009.106. - DOI - PMC - PubMed
    1. Varatharajah Y, Ramanan VK, Iyer R, Vemuri P, Weiner MW, Aisen P, et al. Predicting short-term MCI-to-AD progression using imaging, CSF, genetic factors, cognitive resilience, and demographics. Sci Rep 2019;9. 10.1038/s41598-019-38793-3. - DOI - PMC - PubMed
    1. Petersen RC, Smith GE, Waring SC, Ivnik RJ, Tangalos EG, Kokmen E. Mild cognitive impairment. Arch Neurol 1999;56:303. 10.1001/archneur.56.3.303. - DOI - PubMed
    1. Kelley B, Petersen R. Alzheimer’s disease and mild cognitive impairment. Neurol Clin 2007;25:1–34. 10.1016/j.ncl.2007.03.008.Alzheimer. - DOI - PMC - PubMed
    1. Ahmed S, Haigh A-MF, de Jager CA, Garrard P. Connected speech as a marker of disease progression in autopsy-proven Alzheimer’s disease. Brain 2013;136:3727–37. 10.1093/brain/awt269. - DOI - PMC - PubMed

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