Silent functional magnetic resonance imaging demonstrates focal activationin rapid eye movement sleep

Functional imaging of human sleep has been performed with nuclear medicine methods, but MRI has been difficult to implement, in part because of the no ise associated with echo-planar imaging as well as the difficulty in readin g physiologic signals in the MRI environment. We describe a silent MR seque nce that can record brain activation over many hours with simultaneous acqu isition of an EEG. This shows activation of occipital cortex and deactivati on of frontal cortex during REM sleep, in agreement with previous studies u sing other techniques.