Lecture 9: Sleep And Biological Rhythms

Question 0

What are some recent discoveries on sleep and the brain?

Answer 0

Sleep improves procedural memory - tasks requiring practice and repetition

Also improves problem solving skills and pruning and strengthening of circuits that promotes learning new things and reinforcing old ones

Question 1

What are some reasons we need to sleep?

Answer 1

Body repair
Energy replenishment
Predator avoidance
Thermoregulation
Memory consolidation
Neuronal integrity
Resulting of synaptic populations
Maximising adaptation to the environment

Question 2

What is the result of sleep deprivation on junior doctors?

Answer 2

Impaired performance tests on vigilance
Impaired serial mathematical calculations
Impaired Verbal processing, complex problem solving
Significant decrements in procedural skills post call among surgical trainees
Worsening of stimulated intubation tasks among ED trainees

Question 3

What are the two types of sleep?

Answer 3

REM (rapid eye movement)

Non-REM

Question 4

What are the 4 factor to be considered when diagnosing sleep disorders?

Answer 4

Sleep history
Sleep diary
Actigraph
Polysomnogram

Question 5

What is actigraphy?

Answer 5

A non invasive method of monitoring human rest and activity cycles
The small actigraph unit is worn often under the wrist by the patient to measure gross motor activity
Movement is recorded and the data can be read by a computer and analysed

Question 6

What is a polysomnography?

Answer 6

A type of sleep test which is multi parametric. The test result is called a polysomnograph.
Many body functions are monitored including the brain (EEG), eye movements (EOG), muscle activity (EMG) and heart rhythm (ECG)
Respiratory airflow and effort were also later added

Question 7

When do dreams usually occur?

Answer 7

Mostly during REM sleep

Question 8

What are some reasons for dreaming?

Answer 8

Erasing theory, (dreams are a way of dumping the information we dont need during the day)
filing theory (dreams are a way of storing the information we don't need during the day)

Question 9

How often does REM sleep occur ?

Answer 9

5 times a night, totalling about 2 hours

Question 10

What are some effects of total sleep deprivation?

Answer 10

Death 11-32 days without sleeping
Brownish/disheveled fur
Skin lesions on tails/paws
Increased food intake
20% weight loss
Increased energy expenditure (1.9x increase in energy use)
Decreased body temperature terminally

Question 11

What are some components of sleep history?

Answer 11

Sleep onset
Sleep latency
Interruptions
Total sleep time
Quality of sleep
Long term pattern
Sleep attack
Sleepiness during the day
Sleep walking
Sleep talking
Sleep eating
Sleep sex
Snoring
Violent activities

Question 12

What are some countermeasures for sleep deprivation/fatigue

/sleepiness?

Answer 12

Sleep 2-8 hours before 24 hour shift
15 min nap every 2-3 hour intervals
Sometimes more than 2 hour naps can worsen the sleep inertia

Caffeine

Modafinil

Question 13

What are the three types of sleep problems?

Answer 13

Insomnia (difficulty sleeping)
Excessive day time sleepiness
Parasomnia (abnormal actions while sleeping)

Question 14

What is insomnia? What are its symptoms?

Answer 14

Difficulty sleeping
Can have primary insomnia,
secondary insomnia - due to substances, psychiatric, medical, neurological condition

Can have circadian rhythm problems
Jet lag
Shift work sleep disorder

Question 16

What is excessive daytime sleepiness?

Answer 16

A difficulty in maintaining desired wakefulness
Symptoms:
Falling asleep at inappropriate times

Excessive amount of sleep
Sleep apnoea, narcolepsy/sleep attacks, idiopathic hypersomnia, substances, circadian rhythm disorder, sleep deprivation

Question 17

What is parasomnia?

Answer 17

abnormal actions while sleeping
symptoms include
sleepwalking, eating, talking (somniloquy), REM behaviour disorders, periodic limb movements, restless legs, bruxism

Question 18

How can sleep disorders be managed?

Answer 18

correct diagnosis
multi-model approach (targeting psychological, beahvioural and biological factors)
cognivitve behavrioual teatment for insomnia
light treatment
melatonin
continuous positive airway pressure
medications

Question 19

how can sleep be enhanced?

Answer 19

addressing underlying medical and psychiatric condition
avoiding stimulating substances like caffeine
minimising alcohol intake
adjusting bed firmness, temperature, noise
minimising stimulating activities at night
going to bed when really sleepy
maintain a consistent time in getting out of bed
reducting compuer use at night and turning cellphones off?
have a calm and focused mind (through meditating, focusing on present moment, having your full attention to your current activity)