title: Anodal-tDCS over the human right occipital cortex enhances the perception and memory of both faces and objects.
abstract: Accurate face processing skills are pivotal for typical social cognition, and impairments in this ability characterise various clinical conditions (e.g., prosopagnosia). No study to date has investigated whether transcranial direct current stimulation (tDCS) can causally enhance face processing. In addition, the category- and the process-specificity of tDCS effects, as well as the role of the timing of neuromodulation with respect to the execution of cognitive tasks are still unknown. In this single-blind, sham-controlled study, we examined whether the administration of anodal-tDCS (a-tDCS) over the right occipital cortex of healthy volunteers (N=64) enhances performance on perceptual and memory tasks involving both face and object stimuli. Neuromodulation was delivered in two conditions: online (a-tDCS during task execution) and offline (a-tDCS before task execution). The results demonstrate that offline a-tDCS enhances the perception and memory performance of both faces and objects. There was no effect of online a-tDCS on behaviour. Furthermore, the offline effect was site-specific since a-tDCS over the sensory-motor cortex did not lead to behavioural changes. Our results add relevant information about the breadth of cognitive processes and visual stimuli that can be modulated by tDCS, and about the design of effective neuromodulation protocols, which have implications for advancing theories in cognitive neuroscience and clinical applications.
authors.affiliation: School of Psychology, University of East London (UEL), London, UK; Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy.
authors.forename: Marica
authors.initials: M
authors.lastname: Barbieri
authors.affiliation: School of Psychology, University of East London (UEL), London, UK; Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy.
authors.forename: Marcello
authors.initials: M
authors.lastname: Negrini
authors.affiliation: Department of Psychology and Neuroscience, Leibniz Research Center for Working Environment and Human Factors (IfADo), Dortmund, Germany; Department of Neurology, University Medical Hospital Bergmannsheil, Bochum, Germany.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Nitsche
authors.affiliation: School of Psychology, University of East London (UEL), London, UK. Electronic address: d.rivolta@uel.ac.uk.
authors.forename: Davide
authors.initials: D
authors.lastname: Rivolta
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001245:Association Learning / Q000502:physiology; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology; D005145:Face; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D009778:Occipital Lobe / Q000502:physiology*; D009862:Online Systems; D009949:Orientation / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D065908:Transcranial Direct Current Stimulation; D055815:Young Adult
keywords: Face memory; Face perception; Object memory; Object perception; tDCS