Spiral aftereffect durations following awakening from REM sleep and non-REM sleep

Nine Ss were awakened 2 min after the beginning of a REM period and 2 min after the beginning of a non-REM period (Stage 4), and were tested on a spiral aftereffect. The duration of the spiral aftereffect was found to be longer for the tests made following REM periods than for the tests made following non-REM periods. The results were interpreted to suggest a possible “carry over” effect from the particular sleep, stage into the waking state.