Visualizing virtual brain lesions: Simultaneously combining fMRI and TMS
Baudewig J, Bestmann S, Linden D, Dechent P, Goebel R, Sack A, Kohler A
MR-Research in Neurology and Psychiatry, Medical Faculty, Georg-August-University
Applying transcranial magnetic stimulation (TMS) can temporary and specifically impair behavioural performance. This non-invasive virtual lesion technique thus allows investigating the causal relationship between stimulated brain regions and a specific behavioural or cognitive function. Here we simultaneously combine fMRI and TMS during the execution of behaviourally controlled visuospatial tasks in order to visualize the physiological consequences of a virtual brain lesion as measured by TMS-induced changes of BOLD responses. We found a task-specific behavioural impairment of the TMS that was mirrored by task-specific fMRI signal reductions at the site of stimulation as well as within connected brain structures.