Circadian Rhythms -A-Level Psychology
Biological Rhythms-distinct patterns of changes in body activity that conform to cyclical time periods.
These are regulated by 2 factors:
1)Endogenous pacemaker-internal body clocks e.g. SCN
2)Exogenous zeitgebers-external changes in the environment e.g. social cues,light
Some of these rhythms occur many times a day (ultradian rhythms),others take longer than a day to complete(infradian rhythms).
Circadian rhythms-a type of biological rhythm that is subject to a 24 hour cycle.These regulate the sleep/wake cycle as well as core body temperature.
The sleep/wake cycle:
The fact that we feel drowsy at night and alert during the day demonstrates the effect of daylight(exogenous zeitgeber)
Case study-Siffre’s Cave Study:
He spent several extended periods underground to study the effects on his own biological rhythms
He was derived from natural sunlight and sound but had adequate access to food and drink.
His “free running” biological rhythm stretched to about 25 hours though he slept and woke up at a regular schedule.
This supports the assumption that endogenous pacemakers exert an influence on circadian rhythms.
Case study-Folkard et al
It lasted for 3 weeks and was located in as dark cave.
12 people went to sleep at 11:45pm and woke up at 7:45pm .
The researcher sped up the clock so a day eventually lasted 22 hours.Only one person adjusted to this timing.
This suggests that the existence of a strong free running circadian rhythm that can not be easily overridden by changes in the external environment.
Evaluation Points:
Practical application to shift work-Shift work has been found to lead to desynchronization of circadian rhythms and can lead to adverse and physiological effects.Research by Boivin et al showed that night shift workers suffer a concentration lapse at 6am (a circadian trough) which increases the likelihood of accidents.This research has many economic implications in terms of maintaining worker productivity and preventing accidents in the workplace. Knutsson’s research showed that there is a relationship between shift work and poor health;shift workers are more likely to develop heart disease perhaps due to the stress of adapting to different sleep/wake patterns and lack of poor quality sleep during the day.
Pharmacokinetics-is the action of drugs on the body and how well they are distributed and absorbed.Circadian rhythms coordinate a number of the body’s basic processes such as heart rate,digestion and hormone levels.Research into circadian rhythms has revealed that there are certain peak times during the day or night where drugs are most effective.This has led to the development of guidelines to do with the timing of drug dosing for a range of medications e.eg antiepileptic drugs(Baraldo).
Circadian rhythms are biological rhythms that follow a 24-hour cycle, influencing our sleep-wake cycles, hormone release, body temperature, and other physiological processes.
Circadian rhythms regulate our sleep patterns, with the body naturally being more alert during the day and more tired at night. Disruptions to circadian rhythms can lead to sleep disorders, such as insomnia and jet lag.
External factors such as light, temperature, and social cues can influence our circadian rhythms. Additionally, genetic factors and individual differences can affect our circadian rhythms.
Disruptions to circadian rhythms have been linked to mental health issues such as depression, bipolar disorder, and seasonal affective disorder. It’s important to maintain a regular sleep-wake cycle to support mental health.
Maintaining a consistent sleep-wake schedule, avoiding bright light exposure before bedtime, and avoiding stimulants such as caffeine and nicotine can help regulate circadian rhythms. Additionally, light therapy and melatonin supplements can be used to adjust circadian rhythms.
Understanding circadian rhythms is relevant to topics such as biological rhythms, sleep, and mental health. It’s important for A-Level Psychology students to understand the role of circadian rhythms in these areas and how disruptions can impact our physical and mental health.
Yes, careers related to the study of circadian rhythms include sleep medicine, neuroscience, psychiatry, and psychology research. A strong understanding of circadian rhythms can be useful in these fields.
Still got a question? Leave a comment
Leave a comment