Sleep and Biological Rhythms

ConsciousnessConsciousness refers to an organism’s awareness of itself

and its surroundings.

Levels of awareness:TOP: Controlled processes require attention (and interfere

with other functions)MIDDLE: Automatic processes require minimal attention

(such as riding your bike)LOWEST: Minimal or no awareness of the environment

Controlled ProcessesControlled Processes are

actions that require full awareness ,attention, and focus in order to complete your task. The focused attention required in completing controlled processes usually interferes with the execution of activities in action.

Automatic ProcessesAutomatic processes

are activities that only need minimal focus, and do not distract you from the other activity that’s occurring.

DaydreamingDaydreaming is when

you fantasize or dream while you are awake. This state requires minimal alertness .

Altered StatesAltered states of

consciousness are achieved when using psychoactive drugs, meditation, hypnosis or lack of sleep. These all create a state that is different from the usual consciousness.

HypnosisHypnosis is an altered state of heightened

suggestibility.

The hypnotic state is characterized by:Narrow and focused attention ImaginationPassive receptive attitudeReduced reaction to painHeightened suggestibility

Myths of HypnosisPeople can be hypnotized against their will.

People will do immoral things while hypnotized.

Hypnosis improves memory recall.

Hypnotized persons have special strength.

Hypnosis is fake.

Altered StatesMeditation refers to a

set of techniques that promote a heightened sense of awareness.can involve body

movements and posture, focusing of attention on a focal point, or control of breathing

can induce relaxation, lower blood pressure, and can be associated with a sense of euphoria

Circadian Rhythms Many of our behaviors display rhythmic variation.

Circadian rhythmsOne cycle lasts about 24 hours (e.g. sleep-waking cycle).Light is an external cue that can set the circadian rhythm. Some circadian rhythms are endogenous suggesting the

existence of an internal (biological) clock.

Biological Clocks & its their location

Biological clocks are a timing system embedded in our genetics that control and regulate physiological responses for different periods of time.

Biological Clocks are located in suprachiasmatic nucleus , which makes up the hypothalamus in the brain.

Circadian Problems and Treatments The most common

circadian problems are accidents, jet lag, and resetting the clock

melatonin ( a hormone given by the pineal gland), has proved to help those with disrupted circadian clocks, sleep better.

Light therapy is used to reset the circadian clocks and to treat those who suffer from sleeping disorders.

SleepSleep is a behavior AND an altered state of

consciousness.

We spend about a third of our lives in sleep.A basic issue is to understand the function of sleep.

Myths of SleepEveryone needs 8 hrs of

sleep per night to maintain good health.

Learning of complicated subjects such as calculus can be done during sleep.

Some people never dream.

Dreams last only a few seconds.

Genital arousal during sleep reflects dream content.• May be a useful index of

physical versus psychological causes of impotence in males

Awake but RelaxedWhen an individual closes his eyes but remains awake, his brain activity slows

down to a large amplitude and slow, regular alpha waves (9-14 Hz). A meditating

person exhibits an alpha brain activity.

Stage 1: early, light sleep with slowed breathing, irregular brain waves, potential

hynagogic sensationsStage 2: the brain enters a high-amplitude, slow, regular theta waves (5-8 Hz), spindles

Sleep Stages 1-2

Theta Waves

During deepest sleep (stages 3-4), brain activity slows down. There are large-

amplitude, slow delta waves (1.5-4 Hz).

Sleep Stages 3-4

Stage 5: REM SleepAfter reaching the deepest sleep stage (4),

the sleep cycle starts moving backward towards stage 1. Although still asleep, the brain engages in low- amplitude, fast and regular beta waves (15-40 cps) much like

awake-aroused state.

A person during this sleep exhibitsRapid Eye Movements (REM)

and reports vivid dreams.

Consequences of REM Deprivation

1. Lower stress threshold:When you’re tired, routine activities, such as stopping at the grocery store on the way home from work, walking the dog or picking up the house can feel like overwhelming tasks.2. Impaired memory: Deep sleep fosters the formation of connections between cells, and REM sleep aids in memory formation. Students considering pulling an all-nighter to study for that big exam might do better to get some sleep.

Consequences of REM Deprivation

• Trouble concentrating. When you’re dragging yourself through the day, it’s hard to stay alert and focused. This is why we don’t want our pilots and surgeons to lose too much sleep. Sleep-deprived people have trouble focusing on tasks and overestimate their performance.• Decreased optimism and

sociability.Whether it’s the effort we have to put into staying awake or other factors, sleep deprivation makes us less hopeful and less friendly.

Consequences of REM Deprivation

• Impaired creativity and innovation.

A growing body of research suggests that sleep deprivation may have a particular effect on cognitive processes that rely on our experience of emotions.• Increased resting blood

pressure.Several studies have found that sleep deprivation leads to increased blood pressure (Fujikawa et al., 2009) and even half a night of sleep loss has been reported to increase blood pressure in people with hypertension or pre-hypertension (Lusardi et al., 1996).

Consequences of REM Deprivation

• Increased food consumption and appetite.

Research indicates that acute sleep loss enhances pleasure response processing in the brain underlying the drive to consume food (Benedict et al., 2012). The researchers raise the question of whether chronic sleep deprivation is linked to rising levels of obesity.• Increased risk of cardiac

morbidity. A number of factors can lead to an increased risk of heart attacks, and sleep deprivation is one of them. During experimental sleep deprivation of healthy participants, increases in inflammation associated with the future development of cardiovascular disease occurred.

Why We Dream IPhysiological Function: Dreams provide the sleeping brain with periodic stimulation to develop and preserve neural pathways. Neural networks of newborns are quickly developing; therefore, they need more sleep.

Why We Dream II2. Wish Fulfillment: Sigmund Freud suggested that dreams provide a psychic safety valve to discharge unacceptable feelings. The dream’s manifest (apparent) content may also have symbolic meanings (latent content) that signify our unacceptable feelings.

3. Information Processing: Dreams may help encode a day’s experiences in our LTM.

Why We Dream4. Activation-Synthesis Theory: Suggests

that the brain engages in a lot of random neural activity. Dreams make sense of this activity.

5. Cognitive Development: Some researchers argue that we dream as a part of brain maturation and cognitive development.

All dream researchers believe we need REM sleep. Whendeprived of REM sleep and then allowed to sleep,

we show increased REM sleep called REM Rebound.

1. Insomnia: A persistent inability to fall asleep.

2. Narcolepsy: Overpowering urge to fall asleep that may occur while talking or standing up.

3. Sleep apnea: Failure to breathe when asleep.

Sleep Disorders

Just Funny (2 min): http://www.youtube.com/watch?v=70jFzlxCnZAhttp://www.youtube.com/watch?v=LbmbQkX7czo

Children are most prone to:

Night terrors: The sudden arousal from sleep with intense fear accompanied by physiological reactions (e.g., rapid heart rate, perspiration) which occur during Stage 4 sleep.

Sleepwalking: A Stage 4 disorder which is usually harmless and unrecalled the next day.

Sleeptalking: A condition that runs in families, like sleepwalking.

Sleep Disorders

SADSeasonal Affective Disorder

She doesn’t look very SAD… bud dum bum shee!

Sleep Theories1. Sleep Protects: Sleeping in the darkness

when predators loomed about kept our ancestors out of harm’s way.

2. Sleep Helps us Recover: Sleep helps restore and repair brain tissue.

3. Sleep Helps us Remember: Sleep restores and rebuilds our fading memories.

4. Sleep may play a role in the growth process: During sleep, the pituitary gland releases growth hormone. Older people release less of this hormone and sleep less.

Funny Sleepy Puppy Pictures

More…

Best one…

Crazy Sleeping Disorders!

https://www.youtube.com/watch?v=jtmwuI-j2Pk

Narcolepsy!

http://www.youtube.com/watch?v=Myaonferplk

Kind of funny but really sad at the same time…