title: Transcranial direct current stimulation over right dorsolateral prefrontal cortex enhances error awareness in older age.
abstract: The ability to detect errors during cognitive performance is compromised in older age and in a range of clinical populations. This study was designed to assess the effects of transcranial direct current stimulation (tDCS) on error awareness in healthy older human adults. tDCS was applied over DLPFC while subjects performed a computerized test of error awareness. The influence of current polarity (anodal vs cathodal) and electrode location (left vs right hemisphere) was tested in a series of separate single-blind, Sham-controlled crossover trials, each including 24 healthy older adults (age 65-86 years). Anodal tDCS over right DLPFC was associated with a significant increase in the proportion of performance errors that were consciously detected, and this result was recapitulated in a separate replication experiment. No such improvements were observed when the homologous contralateral area was stimulated. The present study provides novel evidence for a causal role of right DLPFC regions in subserving error awareness and marks an important step toward developing tDCS as a tool for remediating the performance-monitoring deficits that afflict a broad range of populations.
authors.affiliation: Trinity College Institute of Neuroscience and School of Psychology, Trinity College Dublin, Dublin 2, Ireland, and Department of Clinical and Experimental Sciences, University of Brescia, and Istituti di Ricovero e Cura a Carattere Scientifico Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy.
authors.forename: Siobhán
authors.initials: S
authors.lastname: Harty
authors.forename: Ian H
authors.initials: IH
authors.lastname: Robertson
authors.forename: Carlo
authors.initials: C
authors.lastname: Miniussi
authors.forename: Owen C
authors.initials: OC
authors.lastname: Sheehy
authors.forename: Ciara A
authors.initials: CA
authors.lastname: Devine
authors.forename: Sarahjane
authors.initials: S
authors.lastname: McCreery
authors.forename: Redmond G
authors.initials: RG
authors.lastname: O'Connell
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001364:Awareness / Q000502:physiology*; D018592:Cross-Over Studies; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D010775:Photic Stimulation / Q000379:methods; D017397:Prefrontal Cortex / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D016037:Single-Blind Method; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D015854:Up-Regulation / Q000502:physiology
keywords: cognitive aging; error awareness; performance monitoring; prefrontal cortex; tDCS