A selective impairment of semantic memory for words was observed in 7 cases of lobar atrophy with temporal predominance and in a case (H. S.) of herpes simplex encephalitis with a damage to the left anterior temporal lobe (Fig. 6). Semantic memory for faces was also disturbed in a patient (I. K.) whose temporal lobe atrophy is more conspicuous on the right. All the patients preformed the Marie's 3-Paper Test flawlessly and some of them who took the Token Test showed high scores (Table 1). Their aphasic type was diagnosed as Gogi (word meaning) aphasia since they presented with selective impairment in kanji (ideogram) processing as opposed to well-preserved kana (phonogram) processing. In the pateints with focal atrophy, SPECT scans (Fig. 7) revealed that hypoperfusion extended to the middle portion of the temporal lobe, involving both medial and lateral aspects, on the left in all cases and on the right in one case (I. K.) beyond knife-edged atrophic areas in the anterior temporal lobe.
    In the cases of lobar atrophy, words not comprehended were consistent from one occasion to another and lack phonemic cue effects and signs of familiarity. Of a particular interest, the completion phenomenon of proverbs was totally negative except for one case (H. I. ) in which the degree of Gogi aphasia was comparatively mild. These findings indicate that they show a loss of lexicon or a degradation within the verbal meaning representations, themselves. On the other hand, words not comprehended fluctuated from session to session and phonemic cue effects were frequently observed in a case of herpes simplex encephalitis. The completion phenomenon of proverbs was also positive. These findings indicate that he shows a failure to associate the lexical tag and the lexical meaning or a rarefaction of the meaning representations.
    The above findings, consideration of the effects of anterior temporal lobectomy on language functions and neuroanatomical data about the memory system in monkey suggest that semantic memory for words is mainly subserved by the neural network connecting the hippocampal area and the temporal association cortex in the dominant hemisphere, while that for faces is mainly subserved by the homologous structures in the nondominant hemisphere. In addition, pathological process of lobar atrophy with temporal predominance might selectively affect the semantic memory system as a unit.

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     This study examined the comprehension ability of 7 conduction aphasics, using the auditory comprehension part of the syntax test for aphasia designed by Fujita (1981). The results were compared to data on other types of aphasics obtained by Fujita in 1989.
    Four results were obtained. 1 ) Conduction aphasia showed a hierachy similar to that of Broca's aphasia. 2) The conduction aphasics demonstrated greatest difficulties in particle comprehension. 3) As syntactic constructions which potentially intervene in the conduction aphasics'comprehension, we considered word order, location of the agent in the sentence and the complement construction. Word order was shown to have the strongest effect on comprehension. 4) When the conduction aphasics confronted sentences above their ability, they utilized three possible strategies : a) word-order strategy ; considering the first noun as agent and the second noun as subject, b) verb phrase strategy ; constructing a verb phrase and considering the noun in theverb phrase as the subject, and c) morpheme strategy ; understanding the morphemes of passive and active sentences, thus enabling them to change the word-order strategy.

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