Narcolepsy Flashcards
What is narcolepsy?
sudden attacks of sleepiness through the day
What are some of the symptoms of narcolepsy?
hallucinations
sleep paralysis
insomnia
What are episodes normally triggered by?
emotional arousal
What are the 3 explanations of narcolepsy called?
REM
HLA
Hypocretin
REM explanation
Narcolepsy occurred as a result of the malfunction in the systems which maintain REM sleep.
How can REM sleep explain some of the symptoms related to narcolepsy?
REM sleep occurred at the onset of sleep in narcoleptics. Which is why many experience hallucinations and loss of muscle tone.
Evaluation of REM explanation
Looked at cataplexy in narcoleptic dogs and found that cataplexy linked to the activation of cells normally only active during REM sleep, showing those cells could cause narcolepsy. HOWEVER no more evidence supports this.
HLA explanation
These are molecules found on the surface of white blood cells. There has been found to be an increase in one type of HLA in patients with narcolepsy.
HLA evaluation
is HLA found in all narcoleptics?
No, so cannot be sole explanation, it is also common in the general public i.e. those without narcolepsy.
HLA-how would it cause narcolepsy?
By generating an auto-immune attack which results in lower hypocretin cells which are involved in keeping us awake.
Hypocretin explanation
Hypocretin is a neurotransmitter than plays a role in maintaining wakefulness. Narcoleptics have large numbers of hypocretin missing.
Why cant you give narcoleptics hypocretin to boost their numbers?
The molecule is unstable, if given by mouth or injection, it is broken down before it reaches the brain.
What leads to lower levels of hypocretin?
Narcoleptic dogs have a mutation in a gene which disrupts the way hypocretin was processed. However, this results cannot be applied to humans. Narcolepsy doesn’t seem to be down to genes so the lower levels of hypocretin seems to be down to brain injury, stress, dieting or even an auto-immune attack.
An issue with these explanations are that they are biological approaches-explain
They are reductionist as they overlook the impact of individual differences such as personality factors and the ways individuals may benefit from treatments. It ignores other biological explanations and even environmental factors that can cause narcolepsy.
Determinism
These theories suggest that the individual has no control over their condition which may or may not be true for certain individuals.
