Here we show that a core feature of cognitive decline may emerge from the temporal decoupling of neural codes theorized to constitute a flexible frontotemporal circuit for the monitoring and storage of memory contents of real-world information. The work supports theories of neurocognitive aging that propose cortical disconnection underlies age-related cognitive decline 4–6, 9, 10, and suggests that aspects of neurocognitive aging may be related to the declining use of ubiquitous physiological mechanisms of cortical information gating and transmission, indexed by cross-frequency PAC and phase synchronization. However, the weakening of these mechanisms or the absence of their functioning does not appear to be immutable. We developed a noninvasive procedure for directly acting on these mechanisms by matching their preferred resonance frequency on an individual subject basis with that of external alternating current. The results suggest that by customizing electrical stimulation to individual network dynamics it may be possible to influence putative signatures of intra- and inter-regional functional connectivity, and rapidly boost working memory performance accuracy in older adults, with effects that last for 50 minutes and potentially longer.
