title: Non-invasive brain stimulation in Parkinson's disease: Exploiting crossroads of cognition and mood.
abstract: Cognitive impairments and depression are common non-motor manifestations in Parkinson's disease (PD). Recent evidence suggests that both partially arise via the same frontostriatal network, opening the opportunity for concomitant treatment with non-invasive brain stimulation (NIBS) techniques such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS). In this systematic review, we evaluate the effects of NIBS on cognition and/or mood in 19 placebo-controlled studies involving 561 PD patients. Outcomes depended on the area stimulated and the technique used. rTMS over the dorsolateral-prefrontal cortex (DLPFC) resulted in significant reductions in scores of depressive symptoms with moderate to large effect sizes along with increased performance in several tests of cognitive functions. tDCS over the DLPFC improved performance in several cognitive measures, including executive functions with large effect sizes. Additional effects of tDCS on mood were not detectable; however, only non-depressed patients were assessed. Further confirmatory research is needed to clarify the contribution that NIBS could make in the care of PD patients.
authors.affiliation: Department of Neurology and Institute of Clinical Neuroscience and Medical Psychology, Heinrich Heine University, Duesseldorf, Germany. Electronic address: lars.dinkelbach@med.uni-duesseldorf.de.
authors.forename: Lars
authors.initials: L
authors.lastname: Dinkelbach
authors.affiliation: Neuropsychology Unit, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy. Electronic address: mbrambilla@fatebenefratelli.eu.
authors.forename: Michela
authors.initials: M
authors.lastname: Brambilla
authors.affiliation: Neuropsychology Unit, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy. Electronic address: rmanenti@fatebenefratelli.eu.
authors.forename: Rosa
authors.initials: R
authors.lastname: Manenti
authors.affiliation: Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, United Kingdom; Max-Planck Institute of Psychiatry, Munich, Germany; Berenson-Allen Center for Noninvasive Brain Stimulation and Division for Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States. Electronic address: anna-katharine.brem@psy.ox.ac.uk.
authors.forename: Anna-Katharine
authors.initials: AK
authors.lastname: Brem
mesh_terms: D000339:Affect; D001921:Brain; D003071:Cognition; D006801:Humans; D010300:Parkinson Disease; D065908:Transcranial Direct Current Stimulation; D050781:Transcranial Magnetic Stimulation
keywords: Cognition; Dementia; Depression; Non-invasive brain stimulation (NIBS); Parkinson’s disease (PD); Repetitive transcranial magnetic stimulation (rTMS); Transcranial direct current stimulation (tDCS)