A Disproportionate Role for the Fornix in Recall Rather Than Recognition Memory - Tractography Evidence in Temporal Lobe Epilepsy

Mahinda Yogarajah¹, Niels Focke², Silvia Bonelli, Geoff Parker³, Daniel Alexander⁴, Pamela Thompson, Mark Symms, Matthias Koepp, John Duncan

Temporal lobe epilepsy is the most common cause of focal epilepsy, and over one third of patients have seizures that cannot be controlled with medications. Persisting seizures are associated with progressive memory impairment in these patients. Using diffusion tensor tractography we have demonstrated that damage to the fornix in this group, is correlated with material specific memory impairment. In addition, we have demonstrated that the fornix is critical for recall memory, rather than recognition memory. This information aids our understanding of the memory deficits observed in patients with temporal lobe epilepsy.