Factors affecting how much sleep we need
Age (i.e. teenagers need more sleep than adults)
Lifestyle (i.e. leading an active vs. inactive life)
Our Sleep/Wake cycle
This regular cycle, an example of a circadian rhythm, is determined by an internal body clock (the suprachiasmatic nucleus [SCN], located in the hypothalamus in the brain).
Our sleep/wake cycle actually runs closer to 24.2 hrs.
Types of sleep deprivation
Sleep deprivation, not getting the amount of sleep you need, involves partial or total loss of sleep.
Partial sleep deprivation is having some sleep in a 24-hour period but not getting enough to meet your needs.
Total sleep deprivation is going without sleep for an entire 24-hour period, for one night or for several nights.
Psychological effects of sleep deprivation
- Cognitive Difficulties
- difficulty paying attention/concentrating
- difficulty processing information
- difficulty thinking
- memory problems
- impaired creativity
- Affective (feelings) disturbances
- mood disturbances
- lack of motivation
- feelings of fatigue
- Behavioural Difficulties
- slowed performance
- risk-taking behaviour
Physiological effects of sleep deprivation
- slower physical reflexes
- hand tremors
- droopy eyelids
- difficulty focusing eyes
- a heightened sensitivity to pain
- lower energy levels
Conditions linked to sleep deprivation
- Heart Disease
- Anxiety Disorders
Lack of REM sleep is linked with what?
Lack of REM sleep has been linked with:
- Learning problems as REM sleep has been linked with the consolidation of memories.
- REM sleep interrupts the release of some neurotransmitters and this might allow the brain receptors to recover and become more sensitive to their release after a break.
Can you recover from sleep deprivation?
Yes! Most people fully recover quickly from even days of total sleep deprivation. You also don't need to recover an equal amount of sleep to what was lost.
What is sleep debt?
The accumulated amount of sleep loss from insufficient sleep.
What is REM Rebound?
When we sleep after being deprived of REM sleep, we experience a significantly larger amount of time in REM sleep.
What are Microsleeps?
A brief, involuntary period of sleep in the midst of a wakeful activity.
Usually last 3-15 seconds.
Adolescent sleep/wake cycle
- Delayed onset of sleep
- The need for more sleep (9-10 hours sleep per night) than an adult
What is Melatonin?
Melatonin is a hormone that causes sleepiness in humans. It is secreted by the pineal gland, a small structure in the brain, when it is dark.
Tips for getting a better nights sleep?
- Follow a regular routine
- Avoid staying up too late on weekends
- Avoid stimulating activities just before bedtime
- Avoid caffeinated products after 3PM
Effects of sleep deprivation
Nights without sleep
- 1 Night - Discomfort felt but is tolerable
- 2 Nights - Urge to sleep (especially between 2 and 4AM)
- 3 Nights - Tasks requiring concentration are seriously impaired especially if they are simple, repetitive or boring.
- 4 Nights - Periods of microsleeps are unavoidable. Person becomes irritable and confused.
- 5 Nights - Still irritable and confused. May become delusional
- 6 Nights - They may be depersonalisation, with a loss of sense of personal identity and increased difficulty coping with other people and the environment. This is referred to as 'sleep deprivation psychosis'.