Abstracts

Rationale: Research on face recognition in children undergoing temporal lobe surgery has yielded conflicting results on whether lateralized effects are evident and whether there are changes after surgery. These mixed results could possibly be due to small samples, grouping of left and right-sided cases, and the inclusion of extratemporal cases within some of the temporal lobe samples. Here, with a larger sample than previously investigated, we explored change over time, laterality of excision, and whether excision of mesial temporal structures had an effect on face recognition.    Methods: Participants were 68 children and adolescents (IQs = 70) who underwent temporal lobe surgery (39 left, 29 right), subdivided into those with sparing of the mesial structures (lateral group; n=29, 20 left), and those whose temporal lobectomy included resection of mesial structures (n=39, 19 left). Participants completed the face memory subtests of either the Children's Memory Scale or the Wechsler Memory Scale - 3 before and 1 year following surgery. Results: Before surgery, all groups obtained mean scores within the average range on immediate recognition of faces. A Time x Resection Type x Laterality ANOVA yielded no significant effects. For delayed recognition, the right lateral group has a somewhat (albeit not statistically significant) lower score at baseline (within the low average range) compared with the other groups, but again, the analysis did not yield any significant effects.  However, when data were examined at the individual level, more children with left-sided resections than right showed a significant loss (= 1 SD) after surgery on delayed recognition of faces. Conclusions: The face recognition tests used in this study do not appear to be sensitive to laterality of temporal lobe lesion or to resection of mesial temporal lobe structures. At a group level, scores did not change significantly after surgery, suggesting a good outcome with respect to this aspect of visual memory. However, a number of children with left-sided resections declined in performance after surgery, a finding that warrants further investigation of possible predictors of such change. Funding: Funded by EpLink, an integrated discovery program of the Ontario Brain Institute.