AQA PSYA3 - Biological Rhythms - Narcolepsy

The symptoms of Narcolepsy:

• Extreme daytime sleepiness.
• Uncontrollable day-time sleep attacks.
• Cataplexy - sudden loss of muscle tone while awake causing the person to collapse, can be caused by over-excitement and over-arousal.
• Hypnagogic hallucinations - dream-like experiences while awake.
• Sleep paralysis - inability to move while falling asleep or waking up.

Genetic factors:

Lin et al (1999) - linked cataplexy in dogs to a gene defect on chromosome 12

• This gene is responsible for regulating the neurochemical orexin (also known as hypocretin). The defect means it cannot carry out it's normal function.
• A drug used for cataplexy in humans has been shown to be effective on dogs suggesting that the results are relevant.
• There are problems with extrapolating the results from research carried out on dogs with narcolepsy. The inherited nature of narcolepsy in dogs is different…