title: Treatment of visuospatial neglect with biparietal tDCS and cognitive training: a single-case study.
abstract: Symptoms of visuospatial neglect occur frequently after unilateral brain damage. Neglect hampers rehabilitation progress and is associated with reduced quality of life. However, existing treatment methods show limited efficacy. Transcranial direct current stimulation (tDCS) is a neuromodulatory technique, which can be used to increase or decrease brain excitability. Its combination with conventional neglect therapy may enhance treatment efficacy. A 72-year-old male with a subacute ischemic stroke of the right posterior cerebral artery suffering from visuospatial neglect, hemianopia, and hemiparesis was treated with biparietal tDCS and cognitive neglect therapy in a double-blind, sham-controlled single-case study. Four weeks of daily treatment sessions (5 days per week, 30 min) were started 26 days post-stroke. During week 1 and 4 the patient received conventional neglect therapy, during week 2, conventional neglect therapy was combined once with sham and once with real biparietal tDCS. Week 3 consisted of daily sessions of real biparietal tDCS (1 mA, 20 min) combined with neglect therapy. Outcome measures were assessed before, immediately after, as well as 1 week and 3 months after the end of treatment. They included subtests of the Test for Attentional Performance (TAP): covert attention (main outcome), alertness, visual field; the Neglect-Test (NET): line bisection, cancelation, copying; and activities of daily living (ADL). After real stimulation, covert attention allocation toward left-sided invalid stimuli was significantly improved, and line bisection and copying improved qualitatively as compared to sham stimulation. ADL were only improved at the 3-month follow-up. This single-case study demonstrates for the first time that combined application of tDCS and cognitive training may enhance training-induced improvements in measures of visuospatial neglect and is applicable in a clinical context.
authors.affiliation: Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School Boston, MA, USA.
authors.forename: Anna-Katharine
authors.initials: AK
authors.lastname: Brem
authors.affiliation: Department of Neuropsychology, University Hospital Zurich Zurich, Switzerland.
authors.forename: Evelyn
authors.initials: E
authors.lastname: Unterburger
authors.affiliation: Department of Neuropsychology, Zürcher Höhenklinik Wald ZHW, Rehabilitation Center Faltigberg-Wald, Switzerland.
authors.forename: Irving
authors.initials: I
authors.lastname: Speight
authors.affiliation: Division Neuropsychology, Institute of Psychology, University of Zurich Zurich, Switzerland ; Center for Integrative Human Physiology, University of Zurich Zurich, Switzerland ; International Normal Aging and Plasticity Imaging Center, University of Zurich Zurich, Switzerland ; University Research Priority Program "Dynamic of Healthy Aging," University of Zurich Zurich, Switzerland ; Department of Special Education, King Abdulaziz University Jeddah, Saudi Arabia.
authors.forename: Lutz
authors.initials: L
authors.lastname: Jäncke
keywords: cognitive therapy; rehabilitation; stroke; transcranial direct current stimulation; visuospatial neglect