The ability to learn and remember facts, experiences, and skills is critical for a wide range of human activities. Although how experience is encoded into memory, how such memory is then consolidated and later retrived have been extensively studied by psychologists and neuroscientists, a critical context in which memory processing taking place has been understudied. That is the natural rise and fall of the neurochemicals that are known to influence a wide range of brain functions through the sleep and wake cycles. Here Dr. Sara Mednick of the University of California, Riverside (UCR) and Dr. Michael Silver of the University of California, Berkeley (UCB) and their colleagues will investigate how acetylcholine (Ach), a major neuromodulator known to play a critical role in learning and memory, might differentially affect neural processing at the stages of encoding, consolidation, and retrieval. Rivastigmine a drug for treating Alzheimer's Disease, will be given to human subjects to increase Ach just before training (encoding), just after training (consolidation in the waking state), just before bedtime (sleep-dependent consolidation), and just before testing (retrieval). Brain electrical activity will be monitored using high-density electroencephalography (EEG) to characterize how different cortical regions are affected by both natural variations in ACH associated with sleep-wake cycles and by pharmacological treatment. Together, these experiments will provide the critical empirical data to test theories of learning and memory that take into consideration of dynamic changes in neuromodulation
Acetylcholine has been associated with Alzheimer's disease, a neurodegenerative disease that affects over 5 million Americans. Better understanding of ACh's role in mechanisms of memory will help treat patients with the disease and also develop tools for enhancing healthy memory as well. A better understanding of neurochemical mechanisms of learning and memory will also help improve educational practice and applied training regimes, and investigations of the role of sleep in this project will help emphasize the importance of sleep in a society that has record low levels of sleep and impaired functioning due to poor sleep habits. Dr. Mednick and Dr. Silver will develop teaching modules and courses on the roles of sleep and acetylcholine and learning and memory as well as a course on sleep methods that will help train students to conduct research in this area. Finally, Dr. Mednick will present public lectures on the health benefits of sleep at local Hispanic-serving public hospitals and will work with the UCR Health Center to promote napping and healthy sleep habits in college students through Nap-Ins and other university-wide events.
