<prompt> Pontogeniculo-occipital spike is characteristic of which of the following sleep stage?Stage 1 NREMStage 2 NREMStage 3 NREMREM  <response>: Ponto - geniculo - occipital spikes are large phasic potentials, seen in REM sleep. These orginate from cholinergic neurons in pons and pass rapidly to lateral geniculate body and then to occipital coex. 