Frontal-type memory impairment associated with thalamic damage.

The present case report adds further evidence to the hypothesis that material-specific memory problems arise from unilateral thalamic damage and that frontal cortical dysfunction may affect the nature of the memory disorder. A 64-year old patient who had suffered an ischemic lesion limited to the right anterior thalamus showed marked deficits in immediate and delayed recall of visuospatial material and face recognition. In addition, there was evidence of frontal-type memory problems including impaired spatial working memory, increased forgetting rates, poor prospective memory and inadequate elaborative encoding. Concomitant behavioral changes characterized by increased irritability and disinhibition also supported the hypothesis of frontal lobe dysfunction after thalamic damage.