There is evidence of reorganization of somatotopic maps following cortical lesions in mammals such as monkeys, raccoons and rats. However, there has been a striking lack of research on somatosensory plasticity following cerebral damage in adult humans. We describe two individuals with left hemisphere damage who misperceive the locations of tactile stimuli whose presence or absence they can readily detect.We find that the mislocalizations preserve the relative topography of pre-lesion experiences, resulting in shifted and compressed representations of the hand surfaces. These results not only provide evidence for systematic remodeling of somatotopic maps in humans, they also reveal that the systematic changes in cortical topography that have been documented using electrophysiological methods may give rise to similarly systematic changes in somatosensory perception itself. NeuroReport 13:207^211

How does the attentional system coordinate the processing of stimuli presented simultaneously to different sensory modalities? We investigated this question with individuals with neurological damage who suffered from deficits of attention. In these individuals, we examined how the processing of tactile stimuli is affected by the simultaneous presentation of visual or auditory stimuli. The investigation demonstrated that two stimuli from different modalities are in competition when attention is directed to the perceptual attributes of both, but not when attention is directed to the perceptual attributes of one and the semantic attributes of the other. These findings reveal a differentiated attentional system in which competition is modulated by the level of stimulus representation to which attention is directed.

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