Chronic caffeine consumption curbs rTMS-induced plasticity

Megan Vigne; Jamie Kweon; Prayushi Sharma; Benjamin D Greenberg; Linda L Carpenter; Joshua C Brown

doi:10.3389/fpsyt.2023.1137681

Chronic caffeine consumption curbs rTMS-induced plasticity

Front Psychiatry. 2023 Feb 22:14:1137681. doi: 10.3389/fpsyt.2023.1137681. eCollection 2023.

Authors

Megan Vigne¹, Jamie Kweon¹, Prayushi Sharma¹, Benjamin D Greenberg^{1

2}, Linda L Carpenter^{1

2}, Joshua C Brown^{1

2

3}

Affiliations

¹ Neuromodulation Research Facility, TMS Clinic, Butler Hospital, Providence, RI, United States.
² Department of Psychiatry and Human Behavior, Warren Alpert Medical School of Brown University, Providence, RI, United States.
³ Department of Neurology, Warren Alpert Medical School of Brown University, Providence, RI, United States.

Abstract

Background: Caffeine is a widely used psychostimulant. In the brain, caffeine acts as a competitive, non-selective adenosine receptor antagonist of A1 and A2A, both known to modulate long-term potentiation (LTP), the cellular basis of learning and memory. Repetitive transcranial magnetic stimulation (rTMS) is theorized to work through LTP induction and can modulate cortical excitability as measured by motor evoked potentials (MEPs). The acute effects of single caffeine doses diminish rTMS-induced corticomotor plasticity. However, plasticity in chronic daily caffeine users has not been examined.

Method: We conducted a post hoc secondary covariate analysis from two previously published plasticity-inducing pharmaco-rTMS studies combining 10 Hz rTMS and D-cycloserine (DCS) in twenty healthy subjects.

Results: In this hypothesis-generating pilot study, we observed enhanced MEP facilitation in non-caffeine users compared to caffeine users and placebo.

Conclusion: These preliminary data highlight a need to directly test the effects of caffeine in prospective well-powered studies, because in theory, they suggest that chronic caffeine use could limit learning or plasticity, including rTMS effectiveness.

Keywords: caffeine; d-cycloserine; long-term potentiation; motor evoked potentials; plasticity; transcranial magnetic stimulation.

Grants and funding

This research reported in this publication was supported by the National Institute of General Medical Sciences under Award Numbers: P20GM130452, Centers of Biomedical Research Excellence, Center for Neuromodulation.