Cognitive deficits due to asymmetrical bilateral thalamic lesions.

The cognitive deficits are described in a 20-year-old right-handed man with asymmetrical bilateral thalamic lesions and a lesion resulting in the 'locked-in' syndrome. Memory and intellectual assessment, modified due to the physical and communication difficulties, suggested that the patient had little impairment of verbal intelligence and performed normally on memory test involving immediate recall of new material. There was, however, considerable impairment of organization, planning and in the recall of visual and especially verbal memory, over longer periods. Remote memory was relatively intact, except for chronological errors in time-tagged material, and he was disoriented for year, month and day.