A study in the Oct. 29 issue of the Journal of Neuroscience demonstrates a novel role for rapid eye movement (REM) sleep in human memory formation and highlights a significant cognitive consequence of obstructive sleep apnea (OSA). Results show that observed improvements in human spatial navigational memory after a night of normal sleep were significantly attenuated after a night of REM disruption without changes in psychomotor vigilance. Lead author Andrew Varga, MD, PhD, received research support through a Physician Scientist Training Award from the American Sleep Medicine Foundation (ASMF).