Brain activation in patients with congenital bilateral hearing impairment

Twelve patients with idiopathic, congenital, symmetric, moderate-to-severe sensorineural hearing loss participated in this study. Functional magnetic resonance imaging was performed while speech sounds were presented to each patient monaurally. Notable blood oxygenation level-dependent responses were clustered mainly in the superior temporal gyrus and transverse temporal gyrus of both hemispheres during right and left ear stimulation. In addition, the middle temporal gyrus of the right hemisphere was activated during right ear stimulation. The activation pattern was very similar to that of participants with normal hearing. Thus, as long as peripheral acoustic stimulation has not been totally absent from childhood, the classical activation pattern can be elicited in patients with congenital bilateral hearing impairment.