title: The effect of γ-tACS on working memory performance in healthy controls.
abstract: Transcranial Direct Current Stimulation (tDCS) has been widely investigated for its potential to enhance cognition, and in particular working memory, however to date standard approaches to stimulation have shown only modest effects. Alternative, more specialised, forms of current delivery may be better suited to cognitive enhancement. One such method is transcranial Alternating Current Stimulation (tACS) which delivers stimulation at a specific frequency and has been shown to entrain endogenous cortical oscillations which underlie cognitive functioning. To date there has been no comparison of the effects of tACS to those of tDCS on cognitive enhancement. In a randomised repeated-measures study design we assessed the effect of gamma (γ)-tACS, tDCS and sham tDCS on working memory in 18 healthy participants who attended three sessions held at least 72h apart. Pre- and post-stimulation working memory performance was assessed using the 2 and 3-back. Our findings indicated the presence of a selective improvement in performance on the 3-back task following γ-tACS compared with tDCS and sham stimulation. The current findings provide support for further and more detailed investigation of the role of γ-tACS as a more specialised approach to neuromodulation.
authors.affiliation: Monash Alfred Psychiatry Research Centre, The Alfred and Monash University, Central Clinical School, Victoria, Australia. Electronic address: Kate.Hoy@monash.edu.
authors.forename: Kate E
authors.initials: KE
authors.lastname: Hoy
authors.affiliation: Monash Alfred Psychiatry Research Centre, The Alfred and Monash University, Central Clinical School, Victoria, Australia.
authors.forename: Neil
authors.initials: N
authors.lastname: Bailey
authors.affiliation: Monash Alfred Psychiatry Research Centre, The Alfred and Monash University, Central Clinical School, Victoria, Australia.
authors.forename: Sara
authors.initials: S
authors.lastname: Arnold
authors.affiliation: Monash Alfred Psychiatry Research Centre, The Alfred and Monash University, Central Clinical School, Victoria, Australia.
authors.forename: Kirstyn
authors.initials: K
authors.lastname: Windsor
authors.affiliation: Monash Alfred Psychiatry Research Centre, The Alfred and Monash University, Central Clinical School, Victoria, Australia; Department of Psychology, University of South Carolina, Columbia, USA.
authors.forename: Joshua
authors.initials: J
authors.lastname: John
authors.affiliation: Centre for Addiction and Mental Health, Department of Psychiatry, University of Toronto, Ontario, Canada.
authors.forename: Zafiris J
authors.initials: ZJ
authors.lastname: Daskalakis
authors.affiliation: Monash Alfred Psychiatry Research Centre, The Alfred and Monash University, Central Clinical School, Victoria, Australia.
authors.forename: Paul B
authors.initials: PB
authors.lastname: Fitzgerald
mesh_terms: D000328:Adult; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009483:Neuropsychological Tests; D065908:Transcranial Direct Current Stimulation / Q000379:methods*; D055815:Young Adult
keywords: Cognitive load; Gamma; Working memory; tACS