Enhancing memory performance with rTMS in healthy and neurological subjects: the role of the right dorsolateral prefrontal cortex

A debated question in the literature is the degree of anatomical and functional lateralization of the executive control processes subserved by the dorsolateral prefrontal cortex (DLPFC) during recognition memory retrieval.We investigated if transient inhibition and excitation of the left and right DLPFC at retrieval by means of repetitive transcranial magnetic stimulation (rTMS) modulate recognition memory performance in 100 healthy controls (HCs) and in 8 patients with Mild Cognitive Impairment (MCI). Recognition memory tasks of faces, buildings and words were used in different experiments.rTMS-inhibition of the right DLPFC enhanced recognition memory of verbal and non verbal material in both HCs and MCIs. rTMS-excitation of the same region in HCs deteriorated memory performance.Bilateral recruitment of the DLPFC could represent a dysfunctional use of brain resources in recognition memory. Inhibitory rTMS of the right DLPFC may modulate the activity in this dysfunctional network enhancing function in HCs or restoring an adaptive equilibrium in MCI