Sensory gating impairments in poor sleepers during presleep wakefulness.

The neurocognitive model of insomnia predicts information processing deficits in poor sleepers. There is some evidence for deficits in later cognitive processing, but earlier sensory processing remains to be investigated. Paired-click stimuli were delivered to good and poor sleepers in a single night. P50 amplitude to stimuli provided an index of sensory gating in presleep wake, rapid eye movement sleep and stage 2 sleep. Poor sleepers exhibited sensory gating impairments during wake. For both groups, gating was intact in rapid eye movement sleep but absent in stage 2 sleep. These data show that poor sleepers experience enhanced sensory processing in the waking period before sleep. Further study is needed to explore sensory gating in chronic primary insomnia, sleep maintenance insomnia, and across multiple recording nights.