Word deafness is an intriguing neurological syndrome characterized by severe difficulties in the ability to understand or reproduce spoken language with otherwise intact speech production and nonauditory language comprehension. Although symptoms of word deafness can appear in Wernicke's aphasia, the syndrome has been distinguished from Wernicke's aphasia because reading, copying written material, spontaneous writing, and speech are largely unaffected. This pattern of deficit has also been referred to as "verbal auditory agnosia" because deficiencies in processing language are particularly salient in the auditory modality. The disorder is of significant theoretical importance because it supports the modularity of speech recognition from more central language computational networks. However, the specificity and functional locus of the processing disturbances resulting in word deafness remains unclear. This presentation will discuss the nature and potential treatment of word deafness, drawing from data obtained in the course of detailed studies (neuropsychological, neuroimaging and ERP) of rare childhood and adult cases seen in our laboratory. Evidence will be presented that word deafness is based in deficiencies in the spectrotemporal analysis of transient frequency modulations, occurring within a temporal window of a few hundred milliseconds, that provide the foundation for abstracting linguistic information from speech. These deficits can occur in the context of intact processing of temporal features of sound requiring much more refined (millisecond level) resolution of auditory events and therefore represent fairly circumscribed disturbances of temporal processing in the brain that have a profound impact on communication. The potential neurophysiological and neuroanatomical basis for these deficiencies will be proposed.

Gerry Stefanatos is an Institute Scientist and director of the Cognitive Neurophysiology Laboratory at Moss Rehabilitation Research Institute (MRRI). He received his doctorate in Neuropsychology from the University of Oxford where he worked jointly in the University Laboratory of Physiology (with RH Kay and GGR Green) and at the Medical Research Council Neuropsychology Unit (with GG Ratcliff and JC Marshall). His research focused on studies of the neurophysiological basis of developmental and acquired language disorders. Following a postdoctoral fellowship with Doreen Kimura in London, Canada, he moved to the United States and took his first faculty position in the Department of Psychiatry at the University of Texas Health Science Center. Prior to joining the faculty of MRRI, he was Associate Professor in the Department of Neuroscience at Seton Hall University and Clinical Associate Professor in the Department of Psychiatry at Thomas Jefferson University. The current emphasis of his research is on neuropsychological disorders affecting auditory processing and language. This work integrates neuropsychological, neurophysiological, and functional neuroimaging approaches to understanding neuroplasticity and functional reorganization that accompanies recovery from aphasia.