Epilepsy surgery in children: no further threat to theory of mind

Abstract

To investigate whether theory of mind (ToM), an important requirement for adaptive social functioning, is different between children with pharmacologically refractory epilepsy who undergo epilepsy surgery and healthy control children, whether ToM is affected by epilepsy surgery in these children, and whether ToM is associated with demographic or epilepsy variables. The "ToM storybooks", a psychometrically sound ToM instrument designed for children, was administered shortly before and 0.5, one and two years after surgery as part of a neuropsychological assessment. Fifteen patients (mean age: 7.1 years) completed the ToM storybooks before and at least twice after surgery. Two sex- and age-matched healthy control children were included per patient. Linear mixed models were used to analyse differences between patients and controls. The association between ToM and demographic, epilepsy and surgical variables was explored. Patients had lower ToM scores than healthy control children, even when corrected for verbal intelligence quotient (VIQ). Epilepsy surgery had neither a harmful nor a favourable effect on ToM. Later epilepsy onset and temporal origin of epilepsy were associated with higher (better) ToM scores relative to earlier epilepsy onset and extra-temporal epilepsy (including hemispherotomy in one case). Children in whom the amygdala was resected had worse ToM scores. Children with refractory epilepsy have a ToM deficit that may not be accounted for by lower VIQ. Epilepsy surgery does not affect ToM functioning. Younger age at epilepsy onset is associated with poorer ToM, and temporal epilepsy with better ToM. Finally, the amygdala is implicated in ToM deficit. Patients and their parents should be educated about the possible consequences of epilepsy with regards to the development of social cognition and should be guided in order to help improve ToM.