Narcolepsy Flashcards
At what point in someone’s life does narcolepsy begin?
Usually begins in adolescence or early adulthood
What does narcolepsy mean?
The experience of sudden and uncontrollable attacks of sleep at irregular and unexpected times
What is associated with narcolepsy?
Cataplexy
What is cataplexy?
The loss of muscular control
What triggers episodes of narcolepsy?
Emotional arousal
What percentage of narcoleptics have cataplexy?
75%
Name 3 other symptoms of narcolepsy
1) Hallucination
2) Sleep paralysis
3) Frequent waking up
Name the 3 explanations of narcolepsy
1) REM
2) Immune system
3) Hypocretin
When was the REM explanation of narcolepsy created?
In the 1960s
Outline the REM explanation of narcolepsy
It is a result of the malfunction in the symptoms that maintain REM sleep
What evidence is there for the REM explanation of narcolepsy?
One of the symptoms of narcolepsy is cataplexy which is similar to what happens in REM sleep and during the day, sufferers often experience intrusions of REM-type sleep or hallucinations and at night, experience abnormal REM
Name and explain the 2 studies supporting the REM explanation of narcolepsy
1) Vogel (1960) - found REM occurred at the onset of sleep in narcoleptics which explains some symptoms like loss of muscle tone (found in REM) and hallucinations (REM-type sleep)
2) Siegel (1999) - recordings of neural activity in the brainstem of narcoleptic dogs - showed cataplexy co-occurred with brain cell activity that usually only occurs in REM - however general support not convincing
When was the immune system explanation of narcolepsy put forward?
In the 1980s
Outline the immune system explanation of narcolepsy
Narcolepsy is linked to a mutation of the immune system
Name the 3 research studies associated with the immune system explanation of narcolepsy
1) Honda (1983)
2) Stanford Medical Centre (2012)
3) Mignot (1997)
Outline Honda (1983)
Found increased frequency 1 type of human leukocyte antigen HLA which coordinate the immune response and found on the surface of white blood cells
Outline Stanford Medical Centre (2012)
Found more than 90% of narcoleptics with cataplexy found HLA varient - but not all so cannot be the only factor and it is not clear how HLA may lead to narcolepsy