Poster C2, Sunday, March 25, 1:00-3:00 pm, Exhibit Hall C
Improving auditory spatial attention by non-invasive brain stimulation and training
Stephan Getzmann1, Christina Hanenberg1,2, Joerg Lewald1,2; 1Leibniz Research Centre for Working Environment and Human Factors (IfADo), Germany, 2Ruhr University Bochum, Germany
Speech perception in complex acoustic environments usually declines with increasing age. This decline is based – at least in part – on difficulties in detecting and localizing a relevant target speaker among concurrent sound, indicating deficits in selective auditory spatial attention. Our project aims at improving localization of speakers of interest under simulated “cocktail-party” conditions in younger and older human subjects using non-invasive brain stimulation (transcranial direct current stimulation, tDCS) and short-term training. Based on previous findings of beneficial effects of tDCS on behavioral performance (Lewald, 2016, Neuropsychologia 84: 282-293), in Exp. 1 we investigated cortical correlates of improved sound localization using electrophysiological methods. We found that effects on attentional processing occurred after anodal, but not cathodal, tDCS and for targets presented on the side contralateral, but not ipsilateral, to the hemisphere stimulated by tDCS. Electrical imaging indicated specific modulation of activity in a focal region around ipsilateral intraparietal sulcus at the time of the N2 ERP component, reflecting modulation of attentional control. In Exp. 2, two types of short-term training were applied using either synchronized auditory targets and visual stimuli presented at the same location or auditory spatial feedback about the correct location of the target. Here, short-term effects on the behavioral level were found for lower performing participants, as well as related modulations of ERP components by training. Taken together, the present results demonstrate for the first time brain correlates of tDCS- and training-induced plasticity of processes involved in selective auditory spatial attention.
Topic Area: ATTENTION: Auditory