Abstract
Phonemic paraphasia and verbal paraphasia were investigated in relation to focal brain lesions. Regarding phonemic paraphasia, the patients with the lesion in the left prefrontal gyrus showed no different frequency of phonemic paraphasia between the task of confrontation naming and repetition, while the patient with the lesions in the left posterior regions including temporo-parietal lobes showed more significant frequency of phonemic paraphasia in the task of confrontation naming than repetition. This result indicates that phonemic paraphasia can be caused by some different origin in the process of speech : invoking and rearrangement of the target phonemes. The phonemic paraphasia due to left frontal lesion may be possibly caused by the disturbance of realization of phonemes, which did not receive any effect by the difference of modality : confrontation naming and repetition, while the phonemic paraphasia due to the left posterior lesions may be caused by the disturbance in the process of invoking, rearrangement and retrieval of phonemes, which can be improved by the given phonemes in repetition task. Regarding verbal paraphasia, the patients with the left frontal lobe lesions showed no significance of frequency between semantic paraphasia and non-semantic related paraphasia, while the patients with the lesions in the left posterior regions including temporo-parieto-occipital lobes showed more significant frequency of semantic paraphasia than semantically unrelated paraphasia. This fact indicates that the patients with left frontal lesion have a disturbance of selective access to the target related semantic field, while the patients with the left posterior lesions can access the target related semantic fields but cannot select and retrieve a proper target word.
