Chapter 14-2

Question 1

Crepuscular/ vespertine circadian rhythms:

Answer 1

Active at twilight and dawn

Question 2

Lesions to the SCN disrupt:

Answer 2

Sleep/wake cycle, not total sleep

Question 3

PER gene acculumates ____ and is degraded ____:

Answer 3

During the day, at night

Question 4

Genes regulating circadian rhythms and how they’re regulated:

Answer 4

clock, tau, Per1, Per2, Per3, Sleepy 1&2
Self-regulating, entrained by SCN

Question 5

External cues that entrain the internal biological clock:

Answer 5

1. Light/dark cycles
2. Meals, social interactions, physical activity

Question 6

What is melanopsin:

Answer 6

Photopigment in specialized cells in retina for light entrainment.

Question 7

What happens in mice with a small dorsomedial hypothalamic nucleus?

Answer 7

Reduced pre-meal anticipation

Question 7

Light/dark cycle of the SCN entrains what:

Answer 7

Wake/sleep cycle is entrained by the light/dark cycle

Question 8

DHN activity on food entrained mice:

Answer 8

Higher DHN activity

Question 9

Stimulation to sleep-promoting circuits leads to ____:

Answer 9

Sleep

Question 10

Lesions to sleep-promoting circuits leads to ____:

Answer 10

Impaired sleep

Question 11

Brain regions regulating sleep:

Answer 11

1. Reticular formation (nuclei that control different aspects of sleep)
2. Anterior and posterior hypothalamus
3. Basal forebrain

Question 12

Old studies of the neurobiology of sleep concluded that:

Answer 12

Sleep occurs when there is minimal or no sensory input to the forebrain

Question 13

How do we know that old neurobiological sleep studies are incorrect?

Answer 13

We know that sleep is actively regulated by an arousal mechanism in the reticular formation called the reticular activating system

Question 14

REM sleep muscle paralysis theories:

Answer 14

Increased inhibition or decreased excitation of motor neurons

Question 14

Increased inhibition theory of REM sleep muscle paralysis:

Answer 14

Activation of both metabotropic GABAb and ionotropic GABAa/glycine receptors

Question 15

Decreased excitation theory of REM sleep muscle paralysis:

Answer 15

Reduction in glutamate, noradrenaline, dopamine, and hypocretin release

Question 16

Posterior hypothalamus lesions cause:

Answer 16

Promotes wakefulness

Question 17

Anterior hypothalamus lesions case:

Answer 17

Promotes sleep

Question 18

Cholinergic neurons in the basal forebrain promote:

Answer 18

Wakefulness and REM sleep

Question 19

Caffeine is a ___ receptor antagonist, which promotes ____:

Answer 19

Adenosine, wakefulness

Question 20

What is adenosine and how does it accumulate?

Answer 20

• Inhibitory neurotransmitter
• Starts low, accumulates throughout the day
• Accumulation of adenosine enhances deep, slow wave sleep