UC Irvine

The last decade has seen significant progress in identifying sleep mechanisms that support cognition. Most of these studies focus on the link between electrophysiological events of the central nervous system during sleep and improvements in different cognitive domains, while the dynamic shifts of the autonomic nervous system across sleep have been largely overlooked. Recent studies, however, have identified significant contributions of autonomic inputs during sleep to cognition. Yet, there remain considerable gaps in understanding how central and autonomic systems work together during sleep to facilitate cognitive improvement. My dissertation work investigates the independent and interactive roles of central and autonomic activities during sleep and wake in cognitive processing. I specifically focus on the prefrontal-subcortical working memory (WM) processing and mechanisms underlying the formation of hippocampal-dependent episodic long-term memory (LTM). Here, I first present an introduction to heart-brain interaction and memory processing during sleep. Next, I show two experimental studies where I examine the role of autonomic activities and autonomic-central couplings during sleep on WM, which has reliably been shown to benefit from sleep. Lastly, I present a pharmacological within-subjects, double-blind, placebo-controlled study that identifies separate and competing underlying mechanisms between autonomic and central activities supporting WM and LTM. In light of these three studies’ novel contributions, I propose a theoretical model – the Sleep Oscillation Switch (SOS) Model that sleep is a competitive arena in which autonomic WM and LTM vie for limited resources.