Abstract
A right-handed male patient with probable herpes simplex encephalitis is presented because of the rarity of the clinicial picture. Brain X-ray CT scans showed lesions located in the bilateral fronto-temporal regions primarily involving the left lower temporal lobe. The clinical picture following the acute phase of the disease was characterized by specific emotional and behavioral disorders, i.e. oral tendency, hyperactivity, thoughtless talkativeness, random speech and exhilaration, which were partly compatible with the Klüver-Bucy syndrome. Furthermore, this case was characterized by Gogi (word-meaning) aphasia-like transcortical sensory aphasia and neologism produced saliently when naming objects and peculiar neologistic kanji processing in writing to dictation and oral reading. Both the neologism and neologistic kanji processing varied in quantity in parallel with the specific emotional and behavioral disorders. The relationships of these clinical features to lesional sites demonstrated by X-ray CT are discussed.