Chp 12 Sleep deprivation - Psych

Define sleep deprivation?

• condition of not getting sufficient sleep, which can result from a variety of factors

  • Such as: shift work, drug use, poor sleep environment & stressors

How does Shift work cause sleep deprivation?

• Melatonin & Cortisol regulate sleep-wake cycle so ppl awake during day & feel tired @ night

• Shift work alters sleep-wake cycle & consequently reduces quality & amt of sleep

• Ppl work night shift may have trouble sleeping during day bcs exposure to light @ night & dark during day affects circadian rhythm

How do drugs cause sleep deprivation?

• affect progression of sleep stages, reduce amt of NREM sleep or alter REM sleep

• Caffeine: stimulant drug that increases activity in CNS, delays onset of sleep & reduces total sleep time

• Alcohol: can disrupt sleep when sedative effects wear off = cause nighttime awakenings. CNS depressant alcohol relaxes muscles throughout body (including throat) = narrow airway during sleep & increase risk of snoring or obstructive sleep apnoea

How does Sleep enviro cause sleep deprivation?

• Brightly lit environment @ night reduce melatonin production, disrupting natural sleep-wake cycle.

• Environmental noise (inside or outside) may cause awakenings & reduce intensity of sleep

• Room temp & air quality make it harder to fall & stay asleep

How can Stressors cause sleep deprivation?

• make it harder to fall asleep & stay asleep due to heightened anxiety

• Taking longer to fall asleep (sleep latency)

• Disrupt sleep routines, often leading to reduced overall sleep duration

What is Acute sleep deprivation

• occurs bcs short-term lack of sleep over 24hr period, or up to few consecutive nights

• No exact number of hours of sleep constituting acute sleep deprivation

  • However less than 5 hours of sleep within 24hr period general amt

• Immediate effects: typically reverse w adequate sleep

How does acute sleep deprivation affect attention?

• sleep deprivation reduces overall attention & increases lapses of attention where focus temporarily lost

• Occur bcs cognitive processing slows & brain struggles to take in & retain new info, making it harder to concentrate & learn effectively

How does acute sleep deprivation affect Mood?

• significantly altered by sleep deprivation

• Reduce positive emotions & increase negative emotional responses to stressors

• Often leads to irritability, frustration & feelings of anger

How does acute sleep deprivation affect Reflex speed?

Reflex speed: time it takes for signals to travel between neurons

Reaction time: incorporates reflex speed & cognitive processing

• longer reaction times &sleep deprivation slows both processes, leading to delayed response to stimuli

• Impair brain ability to process info & slow down reflexes

How does acute sleep deprivation affect Vision?

• eyes repair themselves during sleep

• Without enough sleep, eyes become itchy, dry, or bloodshot

• Tear production may decrease, raising risk of eye infections

• Sleep deprivation cause blurry vision, involuntary eye twitches & increase sensitivity to light

What is chronic sleep deprivation?

• inadequate sleep for more than a few weeks @ a time, sometimes lasting for years

• Sleep disorder (insomnia) cause chronic sleep deprivation, continual disturbances to sleep or extensive periods of insufficient sleep

• Consequences on overall health! More detrimental than those caused by acute, w outcomes more diffupicuot to reverse

• Can produce psychological effects: anxiety

• Physiological effects: heart disease, obesity

How does deprivation of REM sleep cause harm?

• Overstimulate limbic brain structures that regulate emotion, memory, behaviour & motivation

  • Hippocampus, thalamus, hypothalamus, amygdala

• Heightened activity contributed to increase emotional irritability & reactivity

• Individuals who already experience anxiety disorders, insufficient sleep can worsen symptoms

How does chronic sleep deprivation cause heart disease?

• chronic sleep deprivation elevates stress hormones (cortisol) & increase blood pressure & cholesterol lvls

• Over time, physiological changes place pressure on cardiovascular system & increase risk of developing heart disease

How does chronic sleep deprivation cause Obesity?

• disrupts balance of hormones that regulate appetite

• Cheekiness (hormone stimulate hunger) increases

• Leptin (hormone signals fullness) decreases

• Hormonal imbalance can cause individual to consume more high-energy foods & increase overall food intake

  • = contribute to weight gain & obesity

How does chronic sleep deprivation cause Insomnia?

• sleep disorder characterised by difficulties falling asleep or staying asleep

• Common to wake up not feeling well rested

• Disorder w both psychological & physiological components = result in sleep deprivation

Define sleep hygiene

• behaviour & sleep environment that results in healthy sleep

How does management of electronic devises affect sleep hygiene?

• to maintain sleep-wake cycle = recommended to stop looking at electronic screen at least 1hr before bedtime

• Electronic devices emit blue light = inhibit melatonin production, disrupting circadian rhythm & making it difficult to fall asleep

• Brain stimulation result from electronic device use

• Heightened cognitive alertness & arousal increases sleep latency & may reduce sleep duration & overall sleep quality

How does consistent sleep patterns affect sleep hygiene

• having consistent sleep pattern critical aspect of good sleep hygiene as aids in regulating circadian rhythm

Consistent sleep patterns increase amt of sleep & duration of sleep

• Done by setting bedtime that allows for recommended amt of sleep according to age of individual

• consistent sleep patterns help prevent sleep deprivation

How does creation of healthy sleep enviro affect sleep hygiene?

• Circadian rhythms disrupted by uncomfortable sleeping enviro,

  • therefore recommend that bedroom dark, quiet, & free from distractions (include mobile devices)

• Ned should only be used for sleep or intimacy = help strengthen cognitive link between bed & sleep

• Good airflow & ventilation important as cool & well-ventilated room improve comfort & promote more restful sleep

• Optimal temp 16-20 degrees bcs circadian rhythm regulates changes in body temp across day, promoting higher core temp during daylight hours, & trigger melatonin release & drop in core temp at night.

• Cool room supports natural nighttime temp decline & can therefore can help individuals fall asleep more quickly

What investigation did He study?

Effect of Restricting Bedtime Mobile Phone use on Sleep, Arousal, Mood and Working Memory

He et al.

2020

What is the Effect of Restricting Bedtime Mobile Phone use on Sleep, Arousal, Mood and Working Memory (He et al., 2020)

• randomised pilot trial w students

• Randomised pilot trial preliminary study that tests methods & validity of research & serves as ‘trial run’ for larger study

What is the aim of Effect of Restricting Bedtime Mobile Phone use on Sleep, Arousal, Mood and Working Memory (He et al., 2020)

• to determine how limiting the use of mobile phones before bedtime affects mood, working memory, presleep arousal, sleep quality and sleep habits

What were the participants in Effect of Restricting Bedtime Mobile Phone use on Sleep, Arousal, Mood and Working Memory (He et al., 2020)?

• 38 Uni students from Second Military Medical University in Shanghai China

• → low generalisability

• Had habit of using their mobile phone before bed & experienced poor sleep quality

What tests were using during the study Effect of Restricting Bedtime Mobile Phone use on Sleep, Arousal, Mood and Working Memory (He et al., 2020)?

PANAS: Positive and Negative Affect schedule

N-back task

PSAS: Pre-sleep Arousal Scale

PSQI: Pittsburgh Sleep Quality Index

Online sleep diary

What was the design of Effect of Restricting Bedtime Mobile Phone use on Sleep, Arousal, Mood and Working Memory (He et al., 2020)?

• IV: use of mobile phones during bedtime versus no mobile phone use for 30 mins before bedtime

• DV: mood, working memory, presleep arousal, sleep quality, & sleep habits measured using PANAS, n-back task, PSAS, PSQI, online sleep diary

What was the procedure of Effect of Restricting Bedtime Mobile Phone use on Sleep, Arousal, Mood and Working Memory (He et al., 2020)?

1. Researchers obtained ethics approval from Ethical Committee of University

2. Students from university responded to details posted on social media (voluntary sampling) & provided their written informed consent to participate in study

3. All participants completed before mentioned tests measuring their mood, working memory, presleep arousal, & sleep quality, & recorded their sleep habits via online diary for a week

4. Participants randomly assigned into experimental & control group w 19 participants allocates to each (validity?)

5. Next 4 weeks, participants in experimental grp abstained from using mobile phone 30 mins before planned to go to sleep, control grp continued to use mobile phones per usual

6. @ four-week mark , participants completed same tests as sat during pretesting and these were compared

What were the key findings of Effect of Restricting Bedtime Mobile Phone use on Sleep, Arousal, Mood and Working Memory (He et al., 2020)?

• participants who avoided mobile phone use for 30 mins before bedtime feel asleep faster (reduce sleep latency), slept for longer, experience better sleep quality, report presleep arousal, greater positive affect, less negative affect & show improve working memory

• No mobile phone use show significantly lower PSQI= better sleep quality

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What did Effect of Restricting Bedtime Mobile Phone use on Sleep, Arousal, Mood and Working Memory (He et al., 2020) contribute to psychology?

• relatively recent study that use well-established measures = increase potential for other researchers to replicate study

• Replication = allow researchers to assess reliability if study

What were the limitations of the study?

• sample size small = limit ability to generalise results to population sample was taken from

• → Increase by: increasing sample size, age, job, culture, country

• 4-week intervention period short = prevent examination of long-term effect of restricting mobile phone use before bedtime

• Aside from n-back test & PSQR, all measures were self-report measures = produced subjective data

• → Subjective methods should be combined w physiological measures to prove more objective & less biased data

Why was Effect of Restricting Bedtime Mobile Phone use on Sleep, Arousal, Mood and Working Memory (He et al., 2020) experimental?

• control group

• Pre & post experimental tests