Sleep Flashcards
Circadian Rhythm
Circadian rhythm refers to the changes in bodily functions or activities that occur as part of a biological cycle with a duration of about 24 hours.
Ultradian Rhythm
Ultradian rhythm refers to changes in bodily functions or activities that occur as part of cycle shorter than 24 hours.
Primary sleep disorder:
a sleep disorder that cannot be attributed to another condition such as another sleep disorder, a mental disorder or medical problem, or use of a substance such as a legal or illegal drug.
Secondary sleep disorder:
involves a prominent sleep problem that is a by-product of or results from another condition, or use of a substance.
Circadian Phase Disorders
Circadian rhythm phase disorders are a group of sleep disorders involving sleep disruption that is primarily due to a mismatch between an individual’s normal sleep–wake pattern and the sleep-wake pattern that is desired or required.
Causes of Circadian Phase Disorder
- a mismatch between an individual’s sleep–wake cycle and the sleep–wake schedule required by their school, work or social schedule such as shift work
- a mismatch between an individual’s sleep–wake cycle and the day–night cycle of their physical environment such as jet lag
Sleep-Wake Cycle Shift
This is associated with puberty during adolescence.
During adolescence (13-19 years), the sleep–wake cycle moves back by about 1 to 2 hours (delayed) as the hormone melatonin (sleep hormone) is released 1 to 2 hours later meaning that sleep onset peaks later in the 24 hour cycle. Therefore, the entire sleep–wake cycle is delayed by 1–2 hours in relation to the onset of sleep and consequently the wake-up time
Restoration Theory
This theory proposes that sleep has a restorative function. For example, opportunity to support recovery of the body including the brain to full waking capacity.
Evolutionary Theory
This theory proposes that sleep enhances survival of a species by protecting its members through making them inactive during the part of the day when it is riskiest or most dangerous to move about
Effects of Sleep Deprivation
- Affective: refers to the fact that people tend to have amplified emotional responses including changes in emotional state, mood and ability to control emotions after sleep loss.
- Behavioural: refers to changes in our actions or the way we function after sleep loss.
- Cognitive: refers to changes in mental processes such as attention, logical thinking, learning, memory after just a small amount of sleep loss
Effects on Behavioural Functioning
- Sleep disturbances
- Slower reaction time and speed on tasks.
- Reduced motor coordination, particularly eye–hand coordination
Effects on Affective Functioning
- Amplified emotional responses.
- Mood change.
- Poorer emotion perception.
Effects on Cognitive Functioning
- Lapses in attention and inability to maintain prolonged concentration.
- Reduced alertness due to excessive sleepiness
- Impaired problem solving, decision making, errors in judgment
Dyssomnias
Dyssomnias are sleep disorders that produce difficulty initiating, maintaining and/or timing sleep at a regular time.
Examples of dyssomnias include sleep-onset insomnia
Parasomnias
Parasomnias are sleep disorders characterised by the occurrence of inappropriate physiological and/or psychological activity during sleep or sleep-to-wake transitions.
Examples of parasomnias include sleep walking
Dyssomnia: Sleep-Onset Insomnia
Sleep-onset insomnia is a sleep disorder involving persistent difficulty falling asleep at the usual sleep time, despite having adequate time and opportunity for sleep.
Sleep-onset insomnia is a dyssomnia because it significantly disrupts the sleep–wake cycle process and its regulation as it takes them a much longer time to fall asleep.
Parasomnia: Sleep Walking
Mobility and activity during asleep occurs— activities may vary in type, complexity and duration
Considerable difficulty in arousing/waking during a sleep walking episode because of tendency to be in a deep sleep state
Usually occurs during NREM stages 3 and 4 (and not during REM)
Sleep Walking’s effect on Circadian Rhythm
- There is a loss of deep sleep
- fragmented sleep episode
- causes daytime sleepiness following an episode.
Sleep-Onset Insomnia’s Effect on Circadian Rhythm
- changes in the amount, restfulness and timing of their sleep
- sleep onset tends to occur much later than desired
- sleep tends to be non restorative
CBT: Cognitive Techniques
A CBT therapist can achieve cognitive change in someone with insomnia through the use of techniques that assist the individual in recognising and altering inappropriate or dysfunctional attitudes, beliefs and other thoughts about their insomnia.
This includes:
- addressing anxiety or preoccupation with sleep difficulty and identifying unhelpful thoughts
- learning how to control or eliminate worries about falling asleep and negative thoughts that prevent sleep onset
- promote and offer alternative ways of thinking and interpreting what is making the person anxious or causing concern about sleep so that they are able to think about their insomnia in a different, realistic way.
Sleep hygiene education (SHE) - (Cognitive Behavioural Technique):
provides the patient with information about basic practices that tend to improve sleep. This involves teaching good sleep habits and changing the individual’s basic lifestyle habits.
Stimulus control therapy (SCT) - (Cognitive Behavioural Technique):
strengthens the bed and bedroom as cues for sleep and weakens them as cues for behaviours such as watching TV that are incompatible with sleep as well as to re-establish a consistent sleep–wake schedule.
For example, applying classical and operant conditioning principles and processes to the individual’s bedroom behaviours and practices to re-establish an association between sleep and the bed and bedroom.
- bed/bedroom (Antecedents)
- falling asleep (Behaviour)
- sleep/rest as a positive reinforcer (Consequence)
Bright Light Therapy - (Cognitive Behavioural Technique):
Used for Circadian Rhythm Phase Disorders in which the secretion of melatonin is supressed through timed exposure of the eyes to intense but safe bright light with the aim of shifting an individual’s sleep wake cycle to the desired schedule.
