Physiology

Question 1

What is the differential diagnosis for sexual dysfunction?

Answer 1

Drugs (antihypertensives, neuroleptics, SSRIs, ethanol); diseases (depression, diabetes); psychological (performance anxiety) (p.60)

Question 2

What is dyspareunia and vaginismus?

Answer 2

Sexual pain disorders; considered sexual disfunction disorders (p.60)

Question 3

How is BMI calculated and what values indicate normal, overweight, obese, and underweight statuses?

Answer 3

BMI= (weight in kg)/(height in meters, squared); <18.5 is underweight; 18.5-24.9 is normal; 25-29.9 is overweight; over 30 is obese; over 40 is morbid obesity (p.60)

Question 4

What EEG waveforms are present in the awake state?

Answer 4

Eyes Open, with active mental concentration: Beta (highest frequency, lowest amplitude). Eyes closed: alpha waves (p.61)

Question 5

What is stage N1 sleep, how much time is spent in this stage, and what types of EEG waveforms are present?

Answer 5

Light sleep; 5% of sleep; Theta waves (p.61)

Question 6

What is stage N2 sleep, how much time is spent in this stage, and what types of EEG waveforms are present?

Answer 6

Deeper sleep, bruxism, grinding, clenching; 45% of sleep; Sleep Spindles and K complexes on EEG (p.61)

Question 7

What is stage N3 sleep, how much time is spent in this stage, and what types of EEG waveforms are present?

Answer 7

Deepest, non-REM sleep (slow wave sleep), sleepwalking, night terrors, bedwetting; 25% of sleep; Delta waves (lowest frequency, highest amplitude) (p.61)

Question 8

What is REM sleep, how much time is spent in this stage, and what types of EEG waveforms are present?

Answer 8

Dreaming, loss of motor tone, erections, increased brain O2 use; 25% of sleep; Beta waves (p.61)

Question 9

What part of the brain is essential to initiating sleep?

Answer 9

Raphe nucleus; serotonergic predominance (p.61)

Question 10

How is Sleep enuresis treated?

Answer 10

Oral desmopressin acetate (DDVAP) which mimicks vasopressin. This is preferred over imipramine due to side effects (p.61)

Question 11

What substances/ medications are associated with reduced REM and delta sleep?

Answer 11

Alcohol, benzodiazepines, barbiturates (p.61)

Question 12

What class of drugs is most useful for treating night terrors and sleep walking?

Answer 12

Benzodiazepines (p.61)

Question 13

Describe the duration, neurotransmitters, and physical findings associated with REM sleep.

Answer 13

REM sleep occurs every 90 minutes and duration increases throughout the night. Ach is the principle NT; NE reduces REM sleep. Findings include: variable pulse and BP, Extraocular movements due to activity of PPRF (paramedian pontine reticular formation/ conjugate gaze centre), penile/clitoral tumescence. It decreases frequency with age and has the same EEG patterns as wakefullness (p.61)

Question 14

How are sleep patterns altered in depressed patients?

Answer 14

Decreased slow wave sleep, decreased REM latency, increased REM early in sleep cycle, increased total REM sleep, repeated nighttime awakenings, early morning awakening (p.62)

Question 15

What is narcolepsy?

Answer 15

Disordered regulation of sleep-wake cycles with excessive daytime sleepiness. May include hypnagogic (just before sleep) or hypnopompic (just before awakening) hallucinations. Patient’s narcolepic anc nocturnal sleep patterns begin with REM sleep. Some patients experiencecataplexy (loss of all muscle tone). Strong genetic component (p.62)

Question 16

Compare hypnagogic to hypnopomic hallucinations.

Answer 16

Hypnagogic- right before sleep; hypnopompic- just before awakening (p.62)

Question 17

How is narcolepsy treated?

Answer 17

Daytime stimulants- amphetamines, modafinil and nighttime sodium oxybate (GHB) (p.62)

Question 18

What factors regulate circadian rhythm?

Answer 18

Driven by the suprachiasmatic nucleus (SCN of the hypothalamus) and is regulated by the environment/ light. Controls ACTH, prolactin, melatonin, nocturnal NE release; SCN –> NE release –> pineal gland –> melatonin (p.62).

Question 19

What is sleep terror disorder?

Answer 19

Terror/ screaming in the middle of the night during slow wave sleep. Most common in children; cause is unknown but triggers may cause emotional stress, fever, lack of sleep. Usually episodes are self limited (p.62)

Question 20

What is the difference between nightmares and night terrors?

Answer 20

Nightmares occur during REM sleep and thus memories of the nightmare are possible. Sleep terrors occur during non-REM sleep and there is no memory of arousal (p.62)