This work showed that global spontaneous activity that spreads over the entire cerebral cortex of the neonatal mouse brain occurs almost exclusively during sleep cycles.  We propose that this serves to segregate this activity from more local activity that occurs primarily during wakefulness.  In this work we used frequency-domain analysis of EMG signals to quantify sleep/wake cycles and to trigger stimulation to prevent sleep from occurring.  Activity was measured by calcium imaging of GCaMP signal through the intact skull and the patters of that activity in sleep and wake cycles were quantified using Non-Negative Matrix Factorization.