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Neurostimulation for Memory Enhancement in Epilepsy

  • Epilepsy (CW Bazil, Section Editor)
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Abstract

Purpose of Review

Memory is one of the top concerns of epilepsy patients, but there are no known treatments to directly alleviate the memory deficits associated with epilepsy. Neurostimulation may provide new therapeutic tools to enhance memory in epilepsy patients. Here, we critically review recent investigations of memory enhancement using transcranial electrical stimulation (tES), transcranial magnetic stimulation (TMS), vagus nerve stimulation (VNS), chronic intracranial stimulation, and acute intracranial stimulation.

Recent Findings

Existing literature suggests that transcranial direct current stimulation (tDCS) produces a small enhancement in memory in neuropsychological patients, but transcranial alternating current stimulation (tACS) and transcranial random noise stimulation (tRNS) have not been found to have an effect on memory. Most studies of transcranial magnetic stimulation (TMS) have found that TMS has no positive effect on memory. Vagus nerve stimulation can acutely enhance memory, while chronic therapy does not appear to alter memory performance. We found that there is the most evidence for significant memory enhancement using intracranial stimulation techniques, especially chronic stimulation of the fornix and task-responsive stimulation of the lateral temporal lobe.

Summary

Presently, there are no existing therapeutic options for directly treating epilepy-related memory deficits. While neurostimulation technologies for memory enhancement are largely still in the experimental phase, neurostimulation appears promising as a future technique for treating epilepsy-related memory deficits.

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Acknowledgements

We would like to thank the participants in the studies that contributed data to this work.

Funding

This work was supported by the National Science Foundation (EPSCoR-1632738). NeuroPace, Inc. provided research equipment for use in other ongoing studies being conducted by SM and BCJ. BCJ receives other research support from Medtronic, Sunovion, and the Diamond Foundation.

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Authors and Affiliations

  1. Department of Neurology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA

    Stephen Meisenhelter & Barbara C. Jobst

  2. Department of Neurology, Dartmouth-Hitchcock Medical Center, Lebanon, NH, USA

    Barbara C. Jobst

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  1. Stephen Meisenhelter
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Correspondence to Stephen Meisenhelter.

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Conflict of Interest

Stephen Meisenhelter reports equipment provided by NeuroPace, Inc.

Barbara C. Jobst reports research funding from Medtronic and Sunovion and equipment provided by NeuroPace, Inc.

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This article does not contain any studies with human or animal subjects performed by any of the authors.

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This article is part of the Topical Collection on Epilepsy

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Meisenhelter, S., Jobst, B.C. Neurostimulation for Memory Enhancement in Epilepsy. Curr Neurol Neurosci Rep 18, 30 (2018). https://doi.org/10.1007/s11910-018-0837-3

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