Sex differences in the pre- and postoperative neuropsychological function of epilepsy surgery candidates

Sallie Baxendale, UCL Queen Square Institute of Neurology, London, United Kingdom


Epilepsy surgery is becoming increasingly available for carefully selected people with medically intractable seizures. Prospective candidates require comprehensive presurgical neuropsychological evaluation and follow-up. Many factors combine to create the preoperative neuropsychological profile which forms the basis of formulations regarding lateralised dysfunction and predictions of postoperative outcome. Whilst sex (male/female) is one of a number of factors that is considered in the epilepsy surgery literature, the systematic impact of sex on pre and postoperative function in epilepsy surgery candidates has not been evaluated. The aim of this study was to examine sex differences in cognitive function in the presurgical presentation and postoperative outcomes of people with temporal lobe epilepsy referred for epilepsy surgery.

Participants and Methods:

372 patients (202 Female; 170 Male) with a homogenous underlying pathology (hippocampal sclerosis) underwent a preoperative assessment on tests of intellectual, language and memory function and were followed up one year after undergoing a unilateral temporal lobe resection; n= 169 Right (RTL), n=203 Left (LTL).


There was no impact of sex or laterality of surgery on seizure outcome; 84 % of males and 80% of females were seizure free at follow-up. Prior to surgery, sex effects were evident on tests of verbal memory with females performing better than males. Declines in verbal memory function following surgery were greater in females than males. Being female had a stronger association with postoperative decline on measures of verbal memory, than side of surgery.


There are subtle but significant sex differences in the neuropsychological profiles of people with temporal lobe epilepsy, prior to and following surgery. Whilst females generally perform better than males on tests of verbal memory function prior to surgery they demonstrate greater post operative declines on these measures following surgery. The implications of these findings for clinical practice are discussed.


Category: Epilepsy/Seizures

Keyword 1: epilepsy / seizure disorders - surgical treatment
Keyword 2: cognitive functioning
Keyword 3: assessment