Vagus nerve stimulation…25 years later! What do we know about the effects on cognition?

Kristl Vonck; Robrecht Raedt; Joke Naulaerts; Frederick De Vogelaere; Evert Thiery; Dirk Van Roost; Bert Aldenkamp; Marijke Miatton; Paul Boon

doi:10.1016/j.neubiorev.2014.05.005

Vagus nerve stimulation…25 years later! What do we know about the effects on cognition?

Neurosci Biobehav Rev. 2014 Sep:45:63-71. doi: 10.1016/j.neubiorev.2014.05.005. Epub 2014 May 21.

Authors

Kristl Vonck¹, Robrecht Raedt², Joke Naulaerts³, Frederick De Vogelaere⁴, Evert Thiery⁵, Dirk Van Roost⁶, Bert Aldenkamp⁷, Marijke Miatton⁸, Paul Boon⁹

Affiliations

¹ Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology, Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium. Electronic address: Kristl.Vonck@UGent.be.
² Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology, Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium. Electronic address: Robrecht.Raedt@UGent.be.
³ Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology, Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium. Electronic address: Joke.Naulaerts@UGent.be.
⁴ Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology, Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium. Electronic address: Ferderick.DeVogelaere@UGent.be.
⁵ Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology, Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium. Electronic address: Evert.Thiery@scarlet.be.
⁶ Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology, Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium. Electronic address: Dirk.VanRoost@UGent.be.
⁷ Epilepsy Centre Kempenhaeghe, Postbus 61, 5590 AB Heeze, The Netherlands; Maastricht University Medical Centre, P.O. Box 616, 6200 MD Maastricht, The Netherlands. Electronic address: AldenkampB@Kempenhaeghe.nl.
⁸ Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology, Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium. Electronic address: Marijke.Miatton@UGent.be.
⁹ Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology, Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium; Epilepsy Centre Kempenhaeghe, Postbus 61, 5590 AB Heeze, The Netherlands. Electronic address: Paul.Boon@UGent.be.

PMID: 24858008
DOI: 10.1016/j.neubiorev.2014.05.005

Abstract

VNS therapy was delivered to patients for the first time in 1988. After 25 years, insight in the antiepileptic and antidepressant mechanism of action of VNS has grown steadily. The effects on cognition and especially memory remain controversial. This review provides an elaborate overview of studies addressing cognition and describes potential underlying mechanisms for the reported effects. Short-term VNS has an effect on verbal memory recognition when administered at the correct timing and dosage. Chronic VNS resulted into a positive effect on the cognitive status in an Alzheimer population. Positive effect of chronic VNS in epilepsy or depression patients on global cognitive functioning are less convincing. Neither do the results reveal a negative effect which has major implications for chronic treatment of neurology patients. A cascade of neurochemical processes put in motion by changes in NE concentrations in reaction to stimulation of the vagal nerve may underlie the VNS-induced effects on cognition and memory. In Alzheimer pathology, NE may act as an anti-inflammatory agent on brainstem nuclei.

Keywords: Alzheimer's disease; Cognitive functioning; Depression; Epilepsy; Locus coeruleus; Memory; Norepinephrine; Quality of life; Vagus nerve stimulation.

Publication types

Research Support, Non-U.S. Gov't
Review

MeSH terms

Alzheimer Disease / physiopathology
Alzheimer Disease / psychology
Alzheimer Disease / therapy
Animals
Brain / physiopathology
Cognition / physiology*
Humans
Memory
Vagus Nerve Stimulation / methods*