title: Cerebellar tDCS does not affect performance in the N-back task.
abstract: The N-back task is widely used in cognitive research. Furthermore, the cerebellum's role in cognitive processes is becoming more widely recognized. Studies using transcranial direct current stimulation (tDCS) have demonstrated effects of cerebellar stimulation on several cognitive tasks. Therefore, the aim of this study was to investigate the effects of cerebellar tDCS on cognitive performance by using the N-back task. The cerebellum of 12 participants was stimulated during the task. Moreover, the cognitive load was manipulated in N = 2, N = 3, and N = 4. Every participant received three tDCS conditions (anodal, cathodal, and sham) divided over three separated days. It was expected that anodal stimulation would improve performance on the task. Each participant performed 6 repetitions of every load in which correct responses, false alarms, and reaction times were recorded. We found significant differences between the three levels of load in the rate of correct responses and false alarms, indicating that subjects followed the expected pattern of performance for the N-back task. However, no significant differences between the three tDCS conditions were found. Therefore, it was concluded that in this study cognitive performance on the N-back task was not readily influenced by cerebellar tDCS, and any true effects are likely to be small. We discuss several limitations in task design and suggest future experiments to address such issues.
authors.affiliation: a Department of Neuroscience , Erasmus MC , Rotterdam , The Netherlands.
authors.forename: Brenda W V
authors.initials: BW
authors.lastname: van Wessel
authors.affiliation: a Department of Neuroscience , Erasmus MC , Rotterdam , The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Claire Verhage
authors.affiliation: a Department of Neuroscience , Erasmus MC , Rotterdam , The Netherlands.|b Department of Biomedical Engineering , Zlotowski Centre for Neuroscience, Ben-Gurion University , Beer-Sheva , Israel.
authors.forename: Peter
authors.initials: P
authors.lastname: Holland
authors.affiliation: a Department of Neuroscience , Erasmus MC , Rotterdam , The Netherlands.|c Erasmus University College , Rotterdam , The Netherlands.
authors.forename: Maarten A
authors.initials: MA
authors.lastname: Frens
authors.affiliation: a Department of Neuroscience , Erasmus MC , Rotterdam , The Netherlands.
authors.forename: Jos N
authors.initials: JN
authors.lastname: van der Geest
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D002531:Cerebellum / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D011930:Reaction Time / Q000502:physiology; D065908:Transcranial Direct Current Stimulation / Q000379:methods*; D055815:Young Adult
keywords: Memory; N-back task; brain stimulation; cerebellum; cognitive performance; healthy humans; transcranial direct current stimulation