Abstracts

In previous work, we found that stimulation in the anterior temporal region tends to disrupt auditory but not visual naming, whereas stimulation in the mid to posterior temporal/perisylvian region tends to disrupt both auditory and visual naming. Considering this pattern, we hypothesized that patients with abnormalities in the anterior temporal region would perform more poorly on auditory naming relative to visual naming tasks, whereas patients with abnormalities in the posterior temporal region would perform poorly on both tasks., Subjects were 29 patients with lesion or seizure onset in the left anterior temporal region (defined as [lt] 5cm from temporal pole) and 16 patients with lesion or seizure onset in the posterior temporal or adjacent suprasylvian region. All patients underwent neuropsychological evaluation, including auditory description naming and picture naming tasks. Performance measures from auditory and visual naming tasks were: Accuracy, Response Time, and Number of TOT (tip-of-the-tongue) responses. All scores were converted to z scores based on published norms. Repeated measures, multivariate ANOVA was used to compare auditory and visual naming test scores within the Anterior and Posterior groups, and independent samples t tests were used to compare demographic and clinical data between groups. Classification of individual patients as having [ldquo]anterior[rdquo] vs. [ldquo]posterior[rdquo] dysfunction based on naming performance patterns (i.e., auditory more impaired than visual naming) was assessed via chi square analysis., Auditory naming scores were significantly lower than visual naming scores in the Anterior group for all three measures (Accuracy: P = .001, RT: P =.001, TOT: P = .004). However, there were no significant differences between auditory and visual naming scores in the Posterior group (all P [gt] .05) and group means were all [gt] 2 SDs below normative values. There were also no group differences in age, education, age of onset or Full Scale IQ (all P [gt] .05). Within the Anterior group, 22/29 patients demonstrated auditory naming scores at least 1SD below visual naming (using time-based scores; i.e., RT and TOT), whereas in the Posterior group, only 7/16 patients showed this pattern (chi square P = .03)., Consistent with the topographic pattern of auditory naming sites, patients with anterior temporal abnormalities were more impaired in auditory relative to visual naming, whereas patients with posterior abnormalities were more likely to exhibit comparably poor performances in auditory and visual naming. Additionally, the pattern of poorer auditory than visual naming was predictive of anterior rather than posterior temporal abnormalities in individual patients. These results suggest that performance patterns on auditory and visual naming tasks, in conjunction with other clinical data, might be useful in localizing dysfunction within the temporal region., (Supported by NIH R01 NS35140.)