Word deafness in head injury: implications for coma assessment and rehabilitation.

Pure word deafness, usually involving left hemisphere focal lesions that destroy Heschl's gyrus and/or isolate auditory association cortex, may be rare, but cases with additional perceptual or cognitive symptoms may not be. Word deafness can be transient or evolving, and has been seen in various conditions without identifiable focal lesions. Only two closed head injury cases with focal contusions have been reported; we report two more, with diffuse damage and no focal signs. One patient's symptoms evolved soon after they were recognized. The other patient's unresponsiveness to spoken verbal stimuli persisted despite relatively preserved reading and speech, in a context of poor initiation and moderately severe cognitive impairment. Unrecognized, word deafness following head injury could lead to overestimation of coma duration if transient, and impede rehabilitation if chronic.