Epilepsy surgery within the temporal lobe and its short-term and long-term effects on memory

In patients with pharmacologically intractable, complex-partial seizures, surgical excision of the involved temporal lobe may have significant therapeutic benefit. Resection of mesial structures of the temporal lobes, however, entails a significant risk of decreased memory function. Recent advances in the assessment of memory changes following temporal lobectomy surgery emphasize the complexity of subjective ratings of memory functioning in this population. Neuroimaging tools useful in the diagnostic evaluation of epilepsy surgical candidates have now been shown to be useful in predicting memory change in the post-surgical period. Functional magnetic resonance imaging appears to provide significant information regarding hemispheric representation of language in the temporal lobe epilepsy patient, and the use of this technique to predict memory status following surgery appears promising. Clinical studies involving patients who had temporal lobectomy surgeries have also revealed changes in emotional learning related to the degree of amygdala involvement. Moreover, there is increasing evidence to suggest that differential changes in emotional learning occur among patients with right versus left temporal lobe resections.