Cortical reorganization after acute unilateral hearing loss traced by fMRI

Unilateral acoustic stimulation produces a functional MRI (fMRI)-blood-oxyg enation-level-dependent (BOLD) response mainly in the contralateral auditor y cortex. In unilateral deaf patients, the BOLD response is bilateral. We s tudied a subject with sudden hearing loss after cochlear nerve resection be fore and repeatedly after surgery. During normal bilateral hearing, contral ateral cortical BOLD responses were found. Progressing compensatory reorgan ization with bilateral representation of unilateral stimulation was detecte d over a period of approximately 1 year.