[A case of predominant right thalamic infarction with severe verbal memory disturbance]

We encountered a 45-year-old right-handed man who had suffered a predominant right thalamic infarction and complained of memory loss. Performance on the Miyake Test (recall of ten pairs of related and unrelated words), the Rey Osterrieth Complex Figures, the Benton Test of Visual Retention and the Wechsler Memory Scale-R disclosed a severe verbal memory disturbance associated with a little, if any, visual memory disturbance. An MRI study revealed bilateral lesions limited to the thalamus involving most of the right anterior nucleus (AN), mediodorsal nucleus (MD), ventrolateral nucleus (VL), and centromedial nucleus (CM), as well as a small part of the left MD, and CM. HM-PAO-SPECT scans showed areas of decreased cerebral blood flow not only in the right thalamus but in the medial and basilar region of the right temporal lobe. It is noteworthy that our patient had a predominant right thalamic lesion and exhibited a severe verbal memory disturbance rather than visual memory disturbance. This suggests that the right hemisphere is dominant for verbal memory function in this patient.