CPTP 3.5 - Hypnotics and Anxiolytics Flashcards
How many cycles exist within a typical 8 hour duration of sleep?
Five -
REM sleep (later half)
Slow wave sleep (stage 1 - 4)
In which brain regions is slow wave sleep mediated?
Hippocampus
Neocortex circulatory
Describe four features of slow wave sleep?
Increased amplitude
Slow frequency
Delta wavelength
Memory = reactivation of short-term memory which is integrated into long-term storage
In which brain regions is rapid eye movement sleep mediated?
Cortex
Describe four features of REM sleep?
Decreased amplitude
Increased frequency
Gamma (Y) wavelength
Memory = consolidation into long-term stores (synapses strengthened vis repeated activation)
What acts as the body’s clock pace-maker and where is this found?
Suprachiasmatic nucleus
Hypothalamus - receives inputs from the retina (photosensitive neurones)
What does the suprachiasmatic nucleus activate?
Dorsomedial hypothalamic nucleus
What does the dorsomedial hypothalamic nucleus activate?
- Tuberomammillary nucleus - Histamine
- Raphe nucleus - 5HT
- Locus coereleus - Nor Epi
= Activated - project to cortex and facilitate arousal
Describe the two ways in which sleep is initiated?
- Pineal gland secretes melatonin (inhibits suprachiasmatic nucleus)
- Ventrolateral pre-optic nucleus secretes GABA and Galanine - inhibits tuberomammillary/raphe/locus corueleus nucleus
Why do elderly people suffer more insomnia?
With increased age melatonin secretion decreases
What are the three types of insomnia?
Initial insomnia = difficulty falling asleep
Middle insomnia = wake up repeatedly
Terminal insomnia = wake up too early
Name four causes for insomnia?
Stress
Psychiatric illness
Drugs (SSRI and MAOI - Increased monoamines)
Medical illness
How can stress lead to insomnia?
Active mind
Increased cortisol = interference between hippocampus and neocortex circuitry (SWS)
Increased cortisol also interferes with LTP (REM)
What is the association between anxiety and sleep?
Initial insomnia
What is the association between depression and sleep?
Terminal insomnia
What is the association between bipolar disorder and sleep?
Decreased slow wave sleep
What is the association between PTSD and sleep?
Decreased REM sleep
Define anxiety?
Physical and psychological response to perceived threat - if XS/prolonged = anxiety disorder
Describe the relationship between neurotransmitters in the brain and anxiety?
Decreased GABA-A receptor binding = Increased anxiety
Increased 5HT = Increased anxiety
Increased Nor Epi = PTSD = Increased anxiety
What is the relationship between hypnotics and anxiolytics?
Drugs have common range of activity - depends on DOSAGE used =
Low dose - anxiolysis
Middle dose - concious sedation
High dose - Hypnosis
Name three non-specific CNS suppressants?
Alcohol
Barbituates
Benzodiazapines
Name a benzodiazapine with a short half-life?
Temazepam
8-20 hours half-life
Used as a hypnotic
Name two benzodiazapines with long half-lives?
Chlorodiazepoxide = 6-28 hours (anxiolytic) Diazepam = 20-70 hours (anxiolytic)
Name four adverse effects associated with hypnotic/anxiolytic use?
Barbituates and benzodiazapines are potentated by alcohol
Poor motor co-ordination
Poor memory (decreased REM)
Tolerance and dependence
