Cognitive Enhancement Using Non-invasive Brain Stimulation (NIBS), with Application to Normal and Pathological Cognitive Decline in Aging

Abstract Cognitive decline is an inescapable part of aging, and few effective treatments to remediate such decline have been developed. Recently, the number of non-invasive brain stimulation (NIBS) studies reporting cognitive enhancement have multiplied, opening up the possibility of development of treatments for cognitive decline employing NIBS. Such possibilities are explored in this chapter, beginning with a survey of the current state of NIBS research into treating cognitive decline in normal and pathological aging, focusing on the use of transcranial magnetic stimulation (TMS) and transcranial electric stimulation (TES). The results of present work in the field indicate that cognitive improvements in healthy older adults and in patients with pathological aging such as Alzheimer’s disease can be produced using NIBS, both acutely and possibly in longer-lasting ways, but that much more needs to be done. We then discuss a number of research paradigms to accomplish this goal, beginning first by stressing that engagement with functional brain networks underlying the cognitive processes of interest should be established using NIBS prior to initiating any RCTS. Other techniques to optimize NIBS engagement discussed include use of imaging and computational tools to understand and exploit network interactions, of neural models of plasticity to make predictive choices of NIBS parameters, of online EEG to work with the brain’s oscillatory dynamics, and of functional state targeting to create Hebbian synergies with cognitive functions. Using these techniques in time may lead to the development of effective means of using NIBS to treat cognitive decline in aging.