L33 Coordinating systems Flashcards
What is the process of allostasis
the maintenance of stability through physiological and/or behavioural change and is adaptive in the short term
2 types of things that can cause stress
Major life stressors
Daily hassles
What is the stress response
Hypothalamus -> Pituitary gland -> adrenal gland
Does long term stress have detrimental impacts
Yes
Circadian Rythym: length and how its regulated
Roughly 24hr cycles
Regulated by environmental cues called zeitgebers. e.g. (light exposure, eating, activity, socialising)
What is the Suprachiasmatic Nucleus (SCN)
Specialised group of hypothalamic cells
Function of the Suprachiasmatic Nucleus (SCN)
Recieves information about light exposure from ganglion cells in retina (along retinohypothalamic tract)
Activates melatonin secretion by pineal gland
What did early animal studies into Suprachiasmatic Nucleus (SCN) find
Lesions = no circadian rythym
Transplant SCN from rat with 20 hour period to a rat with 27 hour period recipient adopts the period of the transplanted SCN
What is Melatonin
Sleep-promoting hormone released by pineal gland at night
What is melatonin supressed by
light exposure
When is Dim Light Melatonin Onset
time at which melatonin levels rise above threshold under dim light conditions in laboratory
How are melatonin levels measured
Via saliva or blood samples
What is a reliable marker of individuals circadian phase
melatonin levels
What is social jet leg
Circadian preference misaligned with schedule
What are consequences of short and ill-timed sleep
Cognition & academic performance
Safety (road collisions)
Mental health (depression, anxiety)
Physical health (obesity, long-term conditions)
