Dreaming without REM sleep.
Consciousness and Cognition September 1, 2012 Delphine Oudiette, Marie-José Dealberto, Ginevra Uguccioni et al.
Suppressing REM sleep with the antidepressant clomipramine (50 mg) in 11 healthy young men did not substantially affect dream recall, including report length, complexity, bizarreness, pleasantness, or self-perception of dream or thought-like mentation. REM sleep was suppressed by a marked 81% (range 39-98%). The persistence of long, complex, and bizarre dreams even after partial or total REM suppression suggests that the generation of mental activity during sleep is independent of sleep stage.