Postencephalitic Proper- and Common-name Anomia, Alexia With Agraphia, and Mild Semantic Deficit due to Left Anterior Temporal Lobe Lesion

Here we report the case of an individual who developed proper- and common-name anomia with no category specificity, alexia with agraphia for kanji (Japanese morphograms), and mild verbal and semantic memory impairment after unilateral herpes simplex encephalitis. Although their common-name anomia, alexia with agraphia, and semantic memory impairment resolved within 2 years, this individual continued to experience proper-name anomia and verbal memory impairment. Encephalitic damage was limited to the left anterior temporal lobe (ATL), amygdala, hippocampus, and parahippocampal gyrus, sparing the mid-fusiform and posterior inferior temporal gyri. Although ATL lesions are not typically associated with semantic memory impairment, we suggest that damage to the left ATL can result in both proper- and common-name anomia, as was evident in the current case. In these cases, proper-name anomia may be more severe and persistent than common-name anomia, which may be mild and significantly improved within several years. In cases of semantic memory deficits, persistent common-name anomia, and severe alexia with agraphia, there is typically more extensive involvement of the temporal lobe than seen in the current case, including the mid-fusiform and posterior inferior temporal gyri.