Narcolepsy-cataplexy: deficient prepulse inhibition of blink reflex suggests pedunculopontine involvement

Reflex excitability regulates prepulse inhibition.

Presentation of a weak stimulus, a prepulse, before a reflex-evoking stimulus decreases the amplitude of the reflex response relative to reflex amplitude evoked without a preceding prepulse. For example, presenting a brief tone before a trigeminal blink-eliciting stimulus significantly reduces reflex blink amplitude. A common explanation of such data are that sensory processing of the prepulse ...

Narcolepsy and Cataplexy

After hearing the punch line of the joke, the teenager falls to the floor, almost as if actually punched. She remains there, completely unable to move. She hears her parents reassure her friends that they need not worry about her because she will be all right in a few minutes. She is embarrassed and frustrated as the episode continues, and her friends begin to leave. They bid her goodbye, but s...

Narcolepsy and Cataplexy

Epidemiology [3] Prevalence is estimated as 25 per 100,000 in Caucasian populations. [4] Age of onset is typically around adolescence. A smaller number of cases presents at around 35 years. Less than 5% of narcolepsy with cataplexy occurs in children. One study found that it was often linked to complex movement disorders. [5] It is possible that incidence statistics would increase if diagnostic...

The neurobiology of narcolepsy-cataplexy.

Facilitation as well as inhibition of the blink reflex by a visual prepulse requires intact striate cortex.

OBJECTIVE The role of visual cortex in modulation of the human eye blink reflex was assessed. METHODS Participants were 13 patients with unilateral striate cortex damage. Nonreflexogenic gratings were presented in their intact or blind hemifield prior to white noise or air puff blink-eliciting stimuli. RESULTS Inhibition of reflex amplitude was observed at asynchronies ranging from about 12...