sleep Flashcards
sleep: summarise the functions of sleep and clinical examples of sleep disturbance
3 classifications of sleep deprivation
psychiatric and neurological, neurological, somatic
psychiatric and neurological effects of sleep deprivation
sleepiness, irritability, stress, mood fluctuations, depression, impulsivity, hallucinations; risk factor for seizures
neurological effects of sleep deprivation
impaired attention, memory, executive function; risk of error and accidents; neurodegeneration
somatic effects of sleep deprivation
glucose intolerance, reduced leptin/increased appetite, impaired immunity, increased risk of CVD and cancer, death
what happens to sleep regulation after sleep loss to compensate
reduced latency to sleep onset (get to sleep faster), increase of slow wave sleep (NREM), increase of REM sleep (after selective REM sleep deprivation)
4 potential functions of sleep
restoration and recovery, energy conservation (10% drop in basal metabolic rate), predator avoidance, specific brain functions (memory consolidation)
when do dreams occur
in either REM or NREM, but more frequent and easily recalled in REM
where is brain activity during dreams, and impact on content
higher in limbic system than in frontal lobe, so more emotional than “real-
3 possible functions of dreams
safety valve for antisocial emotions, disposal of unwanted memories, memory consolidation; may have no function (side effect of brain activity when awake)
types of sleep disorders
insomnia, hypersomnia, narcolepsy
duration of insomnia, and impact on life
most transient but some chronic; functional impact on life, and are they falling asleep during day because disrupted sleep cycle
2 classifications of chronic insomnia
physiological and brain dysfunction
2 causes of physiological chronic insomnia
sleep apnoea, chronic pain
3 causes of brain dysfunction chronic insomnia
depression, fatal familial insomnia (primary brain neurodegenerative disease), night working
3 treatments for insomnia
sleep hygiene, hypnotics, sleep cognitive behavioural therapy
how do hypnotics work when treating insomnia
enhance GABAergic circuits
how to improve sleep hygiene
common sense: fixed times, relaxed routine, comfortable sleep environment, not napping during daytime, avoid caffeine nicotine and alcholol late at night, avoid eating heavy meal at night
define hypersomnia
excessive daytime sleepiness
common causes of hypersomnia
obstructive sleep apnoea (keep waking up but don’t remember), restless legs syndrome, nocturnal pain, neurodegenerative disease, medication, noise, anxiety
rare causes of hypersomnia
oesophageal acid reflux, severe bruxism
3 primary causes of hypersomnia
narcolepsy, idiopathic hypersomnolence, post-traumatic brain injury
subjective test for sleepiness
Epworth sleepiness scale
define narcolepsy
falling asleep repeatedly during day and distrurbed sleep during night
3 causes of narcolepsy
cataplexy (sudden, brief loss of voluntary muscle tone, often triggered by strong emotions e.g. laughter), dysfunction of control of REM sleep, orexin/hypocretin deficiency
