Sleep and Mental Wellbeing

Circadian Rhythm Sleep Disorders

Internal circadian rhythm conflicts with daily requirements, resulting in disruption of their circadian rythm

Causes of DSPS

• lifestyle factors

• Poor sleep habits

• Shift work

• Jet lag

• Adolescence

Advanced Sleep Phase Disorder

• lifestyle factors

• Generics

• Shift work

• Jet lag

• Old age

Zeitgeber

External or environmental cues but help synchronise a biological rhythm with the environment. (temperature, light, eating/ drinking habits and exercise)

Bright light therapy

Exposing individual to high intensity light source (15 mins - 2hrs) to adjust a persons circadian rhythm, artificially stimulating or inhibiting melatonin release.

Partial sleep deprivation

Having some sleep in a 24 hour period, but not enough to meet quality or quantity

Full Sleep Deprivation

Going without sleep for a 24 hour period for one or several nights in a row

Cognitive Effects of sleep deprivation

• irritability

• Cognitive impairment

• Memory lapse/loss

• Impaired moral judgement

• Hallucinations

Affective effects

• Mood changes

• Heightened anxiety

• Depression

• Irritability

• Lack of motivation

Behaviour effects

• slower reaction time

• Clumsiness

• Risk taking behaviours

Cognitive effects

• lack of concentration

• Impaired memory (trouble encoding)

• Illogical/ irrational thoughts, poor decision making

• Trouble with simple, monotonous tasks

Physiological effects

• Fatigue

• Trembling hands

• Drooping eyelids

• Staring and inability to focus eyes

• Lack of energy

• Increased pain sensitivity

• Headaches

Micro sleep

Short sharp bursts of sleep (13-15 seconds) where individual may be unaware they have slept

REM rebound

The increase of proportion of REM sleep to catch up

Comparisons to BAC

Affective similarities -Emotional state is altered

Cognitive similarities - decreased concentration, impaired reasoning and complex thought

0.05% BAC

Affective and cognitive effects comparable to 17 hours of sleep deprivation

0.1% BAC

Affective and cognitive effects comparable to 24 hours of sleep deprivation

Full Sleep Deprivation

Missing an entire sleep episode, impairs psychological functioning

BAC Affective similarities

Irritability, reduced emotional regulation

BAC cognitive similarities

Reduced attention poor judgement and impaired decision-making

Bright light therapy

Carefully timed exposure to bright light to help shift circadian timing to align with an individuals required schedule.

Process of bright light therapy

light is detected by the retina, Which signals to The SCN to trigger melatonin release by the Pineal gland.

DSPS bright light therapy

Properly timed morning bright light can advance the circadian rhythm which supports earlier sleep and waking

ASPD bright light therapy

Appropriately timed evening bright light can delay circadian rhythm supporting later sleep and waking.

DSPS and ASPD bright light comparison

for both bright light acts through the retina to change the timing that the SCN stimulates melatonin release from the pineal glandto align circadian rhythm to required schedule.

However for DSPS morning exposure shifts sleep week cycle earlier and for ASD evening exposure shift later

Sleep hygiene

Habits and conditions that support adequate sleep quantity and quality

Daylight

Zeitgeber that indicates the Day night cycle and Influences the SCNs Regulation of melatonin release

Blue light

Can suppress or delay melatonin release Due to simulating daylight

Temperature

Zeitgeber that Affect comfort and sleep continuity, And provides environmental cues

Eating patterns

Zeitgeber that helps synchronise biological rhythms

Drinking patterns

Zeitgeber that influences sleep wake cycle Due to influencing repeated bathroom visits which may interrupt sleep. Caffeine promotes alertness and alcohol Can reduce sleep quality