Biopsych Ltu Jan 2015 Sleep

Front 1

Sleep is a behaviour, like walking and talking. We spend 1/3 of our lives doing it, and it's essential.

What does it do?

1) Conserves ___________

2) It is __________

3) Enforces _______ _____________

4) ___________ consolidation

Back 1

energy; restorative (stress hormones are removed in very deep sleep); niche adaptation; memory

'niche adaptation' is our species-specific characteristics that we developed in response to our needs

Front 2

Learning during sleep- what can you do and not do?

Back 2

You can't learn new facts or listen to a recording to revise while actually asleep. You can consolidate things you learned before you went to sleep (if you sleep for long enough to dream, which we'll catch up with later).

Front 3

What are Circadian Rhythms?

Back 3

During the day, all physiological measure change (up/down). On Earth, we have 24 hr cycles, and within that, 90 minute cycles are common e.g. for thirst. So it's that, basically

Front 4

Daytime rhythms are called _________, night-time are ___________

Back 4

diurnal; nocturnal

Front 5

What's the proper name of your biological clock?

Back 5

Endogenous clock. It's much the same thing as circadian rhythm or clock, either term may turn up. In my case, I'd accept 'bladder', but don't write that on the exam

Front 6

In the absence of external clues, e.g ______ or _________, an animal will maintain some kind of sleep/wake cycle, but it cannot exactly match 24 hrs. This is called _____-__________ and applies to humans as well; on the Mars 500 mock mission, all 6 crew members suffered ______ _________ and were on different patterns, e.g. 25 hour cycle, or 2 sleeps per day.

Back 6

light; temperature; free-running; sleep disorders

Front 7

What is a Zeitgeber?

Back 7

Literally, in German, 'time-giver'. Light is the big one, specifically blue wavelengths

Front 8

Why is watching Netflix on TV while faffing with your smartphone (at 11pm tonight, for example) a bad idea if you need to be up early??

Back 8

You may not sleep very well. Your endogenous clock must receive input from the visual system, and light is a potent Zeitgeber; your screened devices give off the blue wavelengths of light (as does daylight) that convince your endogenous clock that it's isn't bedtime (hence the apps you can get that change the light wavelength automatically, in the line with the sunset time).

Front 9

Where in the brain is your circadian clock?

Back 9

In the hypothalamus (NOT the thalamus!). Specifically, the SCN, or Suprachiasmatic Nucleus. Lesions on the SCN interfere with your rhythms, so you have trouble regulating eating and general activity.

Front 10

Your metabolism is _________ at night

Back 10

lower, obvz

Front 11

Describe what SAD is and give a brief explanation of how it works, and what helps with it. Think about Iceland...

Back 11

Seasonal Adjustment Disorder- a form of depression associated with lack of light in winter.

It's associated with reduced levels of Vitamin D (found in sunlight and also in fish, which is why the fish-gobbling island nation of Iceland don't really get SAD). Vit D has a positive effect on absorption of calcium, used by synapses, so improves brain efficiency.

Front 12

Sleep in the lab- what's an EEG?

Back 12

ElectroEncephaloGram- attached to scalp and/or eyes (muscles, that is)

Front 13

There are 4 types of waves on EEG patterns. Let's name them and what they correspond to, in terms of alertness

Back 13

Alpha- awake

Beta- awake and highly alert

Theta- transitional (drowsy)

Delta- slowest, deep sleep

A- Alpha -Awake and relaxed

B- Beta- Bouncing off the walls

T- Theta- Transitional

D- Delta- Deep sleep

Front 14

Think of/look at EEG wave diagram.

The more ______-________ wave pattern (more up-and- down and jaggy) is actually more ____________

Back 14

active-looking; relaxed

Why? The beta waves account for so much activity that they never really get going, and the measurement translates into more of a fast-moving blur

Make sure you recognise all 4 wave types on a diagram

Front 15

There are 5 stages of sleep- look at the diagram. 1-4 are self-explanatory, and the last one is....

Back 15

REM sleep

Front 16

In stages ___ and ____ of sleep, everything that isn't essential for ________ is 'shut off', so if someone woke you at this point you'd _________ to get going again. In ____ sleep, most of the brain is active and this is when ________ occur, which help us to _________ our ___________.

Back 16

3; 4; survival; struggle; REM; dreams: consolidate; memories

Front 17

In REM sleep, you dream. What nifty safety feature (usually) stops you wandering around and acting it out?

Back 17

The brainstem massively inhibits motor neurons, so almost all muscles are completely relaxed and unable to move, preventing you from moving around and potentially harming yourself

Front 18

In stage 1 sleep, ________ ________ are about slowing things down, e.g. heart rate. In late stage 2 and stage 3, ______ ________ and ___-___________ encourage you to ______ ________ and not wake in response to sounds that would have woken you in stage 1 sleep.

Back 18

vertex spikes; sleep spindles; k-complexes; stay asleep

Front 19

Evolution of sleep: Slow-wave sleep (SWS) is ________; REM sleep is ________. Almost all __________ display both, and also birds.

Back 19

ancient; newer

Front 20

Bonus question: What's weird about dolphins?

Back 20

Their brain shuts down one hemisphere for sleep at a time, rather than both as in most animals, because they have to go to the surface to breathe.

Also, they have prehensile penises (that is, they can grasp things with it, like an elephant's trunk), which is another weird thing but not the answer :)

Front 21

Elderly people sleep less well than younger people; why?

Back 21

They have fewer sleep spindles, meaning they are more easily roused from early stages of sleep, and consequently they have less restorative deep sleep, less recovery and faster aging.

Front 22

How many calories are used per hour of sleep?

Back 22

65. Jogging for an hour will burn around 470 calories (150lb female), so that's about 7 and a bit hour's kip!!

Front 23

The brain is able to sleep, wake and dream if isolated from the ________ ____, but if the _______ _______ is isolated from the __________, the animal will remain in short-wave sleep.

Back 23

spinal cord; brain stem; forebrain

That is to say, the forebrain= SWS (restorative sleep), and the brain stem= wakefulness and REM

Front 24

The ______ ________ ______ (RAS) is in the brain stem, and is responsible for ____________ sleep-wake transitions; it signals to the ___________ , which secretes ___________ and _________, for alertness. Problems such as lesions in the RAS can put the brain into a coma as it isn't 'ordered' awake

Back 24

Reticular Activating System; regulating; hypothalamus; hypocretin and histimine

Front 25

What are the 2 sleep disorders we know about and what's the difference between them?

Back 25

Insomnia is a difficulty in initiating and/or maintaining sleep e.g. as in sleep apnea, where breathing problems will wake the sufferer.

Narcolepsy is characterised by excessive and/or frequent 'attacks' of sleep, and sleep paralysis

Front 26

Insomniacs often take sleeping pills which help at first, but over time they _______ ___ _________. Insomniacs have been shown to fall asleep ________ and for _________ than they believe, but the real issue is that they do not reach ____________ sleep stages. They also suffer from ___________ _____ _________

Back 26

make it worse (sleeping tablets increase risk of stroke!); sooner; longer; restorative; Restless Legs Syndome

Front 27

Narcolepsy is essentially instant REM sleep- instant _________ and ________. It can be brought on by sudden emotion.

___% of sufferers carry ______ gene, which induces an ______-________ response against the _________-producing cells in the __________.

Back 27

paralysis; dreaming; 90; HLA; auto-immune; hypocretin; hypothalamus