Pre-activating the mesial temporal lobe facilitates learning

While numerous neuroimaging studies have been conducted to examine brain activities associated with different cognitive tasks, few have focused on the effects of temporary increase in blood oxygen level on subsequent cognitive performance. The present study aimed to study this temporary hemodynamic change on subsequent learning. Using the novel picture encoding task (NPET) to activate the hippocampus, the present functional magnetic resonance imaging study showed that the level of blood oxygen level-dependent signals in the mesial temporal lobe associated with NPET positively predicted memory performance after engaging in the NPET for normal controls and patients with temporal lobe epilepsy. In addition, patients demonstrated significantly greater improvement on memory performance than normal controls. Though the improvement was transient, these results provided a neuro-physiological evidence to support our previous hypothesis that the functioning of a specific brain region can be facilitated by performing a task mediated by the same region.