Neuromodulation for restoring memory

Abstract

Disorders of learning and memory have a large social and economic impact in today's society. Unfortunately, existing medical treatments have shown limited clinical efficacy or potential for modification of the disease course. Deep brain stimulation is a successful treatment for movement disorders and has shown promise in a variety of other diseases including psychiatric disorders. The authors review the potential of neuromodulation for the treatment of disorders of learning and memory. They briefly discuss learning circuitry and its involvement in Alzheimer disease and traumatic brain injury. They then review the literature supporting various targets for neuromodulation to improve memory in animals and humans. Multiple targets including entorhinal cortex, fornix, nucleus basalis of Meynert, basal ganglia, and pedunculopontine nucleus have shown a promising potential for improving dysfunctional memory by mechanisms such as altering firing patterns in neuronal networks underlying memory and increasing synaptic plasticity and neurogenesis. Significant work remains to be done to translate these findings into durable clinical therapies.

Keywords: AD = Alzheimer disease; Alzheimer disease; DBS = deep brain stimulation; GABA = γ-aminobutyric acid; MMSE = Mini-Mental State Examination; NBM = nucleus basalis of Meynert; NMDA = N-methyl-d-aspartate; PD = Parkinson disease; PPN = pedunculopontine nucleus; STN = subthalamic nucleus; TBI = traumatic brain injury; deep brain stimulation; memory; traumatic brain injury.