An autopsy case of a 56-year-old right-handed male with mixed dysphasia due to left thalamic hemorrhage was reported. is clinical symptoms began with weakness of the right leg and consciousness disturbance. He was admitted immediately to Kuwana hospital. On admission he was in a drowsy state with right hemiparesis, dysarthria and naming disorders. A CT scan revealed a hematoma ( 16 × 18 × 25 mm in diameter) in the left thalamus. On the 6th hospital day he had become alert, SLTA showed distinctive features of mixed dysphasia with severe acalculia. With improvement of the right hemiparesis and dysarthria, the symptoms of mixed dysphasia gradually faded away and became almost undiscernible on the 27th hospital day. However, acalculia and disorders of constructive praxis persisted. Perforation of gastric ulcer and subsequent sepsis resulted in death on the 64th hospital day. Postmortem examination of the brain showed a small hematoma ( 12 × 12 × l5 mm in diameter ) in the thalamus and posterior limb of the internal capsule on the left side. The localization of the hematoma was investigated, according to Schaltenbrand's atlas. The hematoma involved the thalamic nuclei of D. im. e., D. im. i., Z. im. e., Z. im. i., Ce., V. im. e., V. im. i., V. c. e., V. c. i., V. c. par., V. c. pc. and V. c. por.. The aphasic symptoms were transient and discernible only in the acute period. This suggests that the aphasic symptoms were caused by the hematoma itself and its accompanying effects in the acute period such as compression and edema on the pulvinar and other adjacent structures which have thalamo-cortical association fibers.
Three cases of mirror writing ( MW) with left thalamic hemorrhage were reported. All were right handed and the MW was limited to the left hand. All showed slight deficit in short term memory and in calculation. But none showed constructional difficulty or unilateral spatial neglect. Only one of them was considered as aphasic. MW was seen in voluntary writing and on dictation. Eye closure facilitated the tendency for MW. Also, it became more prominent when they had to write laterally from right to left than from left to right or in vertical direction. Automatic writing also facilitated the tendency while attention tended to suppress it. This tendency for MW seemed to fluctuate according to the level level of attention. As for the mechanism of MW in three cases, we discussed a possible role of the left thalamus. MW in the left hand can be seen in normal person under certain conditions. Therefore the MW seen in these cases may simply be a disclosure of the normal latent tendency. Lesions in the left thalamus may have contributed to the appearance of the MW by disturbing the attentional mechanism.