Brain stimulation ‐induced neuroplasticity underlying therapeutic response in phantom sounds

Abstract
Noninvasive brain stimulation can modify phantom sounds for longer periods by modulating neural activity and putatively inducing regional neuroplastic changes. However, treatment response is limited and there are no good demographic or clinical predictors for treatment outcome. We used state‐of‐the‐art voxel‐based morphometry (VBM) to investigate whether transcranial magnetic stimulation‐induced neuroplasticity determines therapeutic outcome. Sixty subjects chronically experiencing phantom sounds (i.e., tinnitus) received repetitive transcranial magnetic stimulation (rTMS) of left dorsolateral prefrontal and temporal cortex according to a protocol that has been shown to yield a significantly higher number of treatment responders than sham stimulation and previous stimulation protocols. Structural magnetic resonance imaging was performed before and after rTMS. In VBM whole‐brain analyses (P < 0.05, FWE corrected), we assessed longitudinal gray matter changes as well as structural connectivity between the ensuing regions. We observed longitudinal mesoscopic gray matter changes of left dorsolateral prefontal (DLPFC), left operculo‐insular, and right inferior temporal cortex (ITC) in responders (N = 22) but not nonresponders (N = 38), as indicated by a group × time interaction and post‐hoc tests. These results were neither influenced by age, sex, hearing loss nor by tinnitus laterality, duration, and severity at baseline. Furthermore, we f...

Source: Human Brain Mapping - October 24, 2017 Category: Neurology Authors: Timm B. Poeppl, Berthold Langguth, Astrid Lehner, Thomas Frodl, Rainer Rupprecht, Peter M. Kreuzer, Michael Landgrebe, Martin Schecklmann Tags: Research Article Source Type: research