Altered states Flashcards
What is a circadian rhythm
A behavioural or physiological cycle that takes place over a 24 hour period
Give examples of circadian rhythms
Sleep wake cycle, body temp, altertness, reaction time.
Exogenous factors
Daily habits such as reading before bed, washing face, etc.
Endogenous factors
Light, melatonin production
How does light control the sleep wake cycle
- Light enters eyes and falls on the retina
- the retina sends a signal through the optic nerve to the superachiasmatic nucleus
- the superachiasmatic nucleus then sends a message to the pineal gland in the hypothalamus telling it to reduce or increase the production of melatonin
Why do we need sleep
Energy conversation
Memory consolidation
Repair and restoration
Amplitude
Height
Frequency
close together
Stage one sleep
alpha and theta waves + hypnic jerks
Stage two sleep
Theta waves + sleep spindles (High frequency) and K complexes (High amplitude)
Stage three sleep
Less than 50% delta waves + deep sleep+ slow waves
Stage four sleep
50+% delta waves
Stage five
REM + alpha and theta similar to wakefulness
Sleep Apnoea
Periodically stop breathing either due to obstruction or central sleep (Due to a delayed signal to the brain)
Results in high blood pressure and heart problems
Sleeping on side, weight loss and C-PAP
C-PAP
Continous Postitive Airway Pressure