Social and environmental contexts modulate sleep deprivation-induced c-Fos activation in rats.

•Rats were sleep-deprived for 2h using three voluntary/forced deprivation methods.•The patterns of c-Fos activation in the brain varied with the deprivation method.•Voluntary exploration with or without social interaction activated select regions.•Forced, gentle sensory stimulation was least effective in inducing c-Fos.•The brain responds to voluntary and forced sleep deprivation differently.