Caffeine and cortical excitability, as measured with paired-pulse transcranial magnetic stimulation.

Kristine Strunge, Hugh Bostock, James Howells, Bülent Cengiz, Gintaute Samusyte, Martin Koltzenburg, Hatice Tankisi

Journal: Muscle & nerve 2024;69(2):206-212

PMID: 38124685

Full Text on Ovid Technologies, Inc. View on PubMed

Abstract

INTRODUCTION/AIMS

The transcranial magnetic stimulation tests of short-interval intracortical inhibition (SICI) by both conventional amplitude measurements (A-SICI) and threshold-tracking (T-SICI) are important methods to investigate intracortical inhibitory circuits, and T-SICI has been proposed to aid the diagnosis of amyotrophic lateral sclerosis. Beverages containing caffeine are widely consumed, and caffeine has been reported to affect cortical excitability. The aim of this study was to determine whether these SICI tests are affected by caffeine.

METHODS

Twenty-four healthy subjects (13 females, 11 males, aged from 19 to 31, mean: 26.2 ± 2.4 years) were studied in a single fixed-dose randomized double-blind placebo-controlled cross-over trial of 200 mg caffeine or placebo ingested as chewing gum. A-SICI and T-SICI, using parallel tracking (T-SICIp), were performed before and after chewing gum.

RESULTS

There was no significant change in SICI parameters after placebo in A-SICI (p > .10) or T-SICIp (p > .30), and no significant effect of caffeine was found on A-SICI (p > .10) or T-SICIp (p > .50) for any of the interstimulus intervals.

DISCUSSION

There is no need for caffeine abstention before measurements of SICI by either the T-SICI or A-SICI measurements.

Address: Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark.; Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK.; Central Clinical School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia.; Department of Neurology, Gazi University Faculty of Medicine, Ankara, Turkey.; Department of Neurology, Hospital of Lithuanian University of Health Sciences Kauno Klinikos, Kaunas, Lithuania.; Department of Neurology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania.; Department of Clinical Neurophysiology, National Hospital for Neurology and Neurosurgery, London, UK.; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.

DOI: 10.1002/mus.28027

Link outs

Subscription / membership required

Full Text Sources:

MeSH Terms: Female, Humans, Male, Caffeine, Chewing Gum, Cortical Excitability, Evoked Potentials, Motor, Motor Cortex, Neural Inhibition, Transcranial Magnetic Stimulation, Young Adult, Adult