AP Consciousness

“To sleep, perchance to dream.”William Shakespeare

Today’s Opening Assignment

1. Clear your desks

2. Get comfortable

3. Go to sleep

What is Consciousness?

• A person’s awareness of the world around him/her.

• Individual consciousness can vary • If consciousness varies to the point that it

considerably varies from the norm, it is termed an altered state of consciousness (ASC).

• The cycle of wake & sleep is known as circadian rhythm. The chemical melatonin plays a key role in the regulation of sleep/wake cycles.

The Default Mode Network

• Old view of consciousness: The brain was “on” only when a person is awake.

• Current view: Research indicates that the brain is always “on,” regardless of whether a person is awake or asleep.

• In fact, according to research, certain areas of the brain (e.g. lateral parietal cortex, medial prefrontal cortex) are more active (up to 20X) during sleep than when awake (Raichle).

• This has been termed the default mode network

• Believed to play a major role in learning and memory

• Also may be linked to Alzheimer’s, clinical depression, and schizophrenia (Raichle; also Whitfield-Gabrieli, 2008).

Sleep

• Why do we sleep?Answer: unknown• It is known that all humans need to sleep;

without it, hallucinations will occur. If a person does not sleep, eventually they will die.

• Sleep needs will vary with age.• There are four stages of sleep; most dreaming

takes place in Stage 1. Some separate REM stage sleep into a different stage altogether.

Sleep Disorders

• Sleep apnea: interruption of breathing during sleep. Person afflicted will snore because their windpipe is blocked, which causes the person to wake up repeatedly throughout the sleep cycle. Can be fatal.

• Insomnia: inability to sleep. Linked with anxiety and/or depression

• Narcolepsy: The immediate falling to sleep (often REM) from wake.

Sleep Disorders

• Somnambulism: sleepwalking. Occurs on NREM sleep. Can be very dangerous. Sleeptalking (somniloquy) also occurs during NREM sleep.

• Night terrors: Occurs during Stage 4 sleep, not during dream state. Features fear-producing episodes combined with movement of the person affected. Not the same as nightmares.

Dreams

• Everyone dreams• Dreams occur during REM sleep. Recent research also

indicates that dreams occur during NREM sleep (Stickgold).

• REM= Rapid Eye Movement• Your ability to remember dreams depends on waking

up during/right after REM sleep.• REM sleep typically begins during the second time of

Stage 1 sleep.• Dreams occur 3-5 times during sleep

REM Dreams v. NREM Dreams

• REM dreams are longer. REM dream states also increase throughout the night.

• NREM dreams are associated with positive emotions, while REM dreams are associated with negative emotions

• Ratio of NREM to REM dreams may be related to depression

• Research indicates that NREM dreams make memories more useful in future applications of what has been previously experienced/learned

Dream Theory

• Research indicates that dreams occur in real time.• Freudian Theory: Dreams indicate a pathway into a

person’s true self. Dreams contain symbols of what the person is consciously unaware.

• Activation-Synthesis: Dreams are composed of bizarre combinations of a person’s working memory.

• Continual-activation (Zhang, 2004): During sleep, information is stored into long-term memory. Dreams are a byproduct of the storage process. REM sleep also seems to foster neurogenesis (Guzman-Marin et al, 2008; Meerlo et al 2009).

Can Dreams Be Seen?

• Scientists at the University of California-Berkeley have used fMRI technology to model not only what subjects think about when awake, but what they dream about while asleep

• Images are crude at the moment, but are believed to become sharper in detail in the future.

Drugs

• What is a drug?Any substance that changes a person’s behavior.

Drugs taken for recreational purposes are psychoactive.

What is the most used drug in the U.S.?

What is the most abused drug in the U.S.?

Drug Classes

• Stimulants: Drugs that accelerate the brain & body (caffeine, nicotine, cocaine, methamphetamine).

• Depressants: Drugs that slow down the brain & body (alcohol, barbiturates, morphine, opium). Depressants are split into those that are pain-killers (opiates), and those that make the user drowsy (sedatives).

• Hallucinogens (aka psychedelics) : Drugs that generate changes in perception detached from physical reality (LSD, marijuana, peyote, mushrooms).

Note: The drug MDMA (aka Ecstasy) is a compound that is both stimulant and hallucinogen.

Drug Use in the U.S.

• ONDCP (Office of National Drug Control Policy, 2007) stats:

Among Youth (12-17):Any illicit drug: 9.5%Marijuana: 6.7%Cocaine: 0.4%Methamphetamine: 0.1%Illicit use of prescription drugs: 3.3%Hallucinogens: 0.7%Overall drug use down from 11.6%

ONDCP Stats, cont.

• Among young adults (17-25):Cocaine: 1.7 %Meth: 0.4

Most commonly used illegal drugs used by first time users:

1. Prescription Drugs (2.5 million)2. Marijuana (2.1 million)

Commercials

• Please watch the following commercials, and answer the following questions:

1. Which commercial is the most effective, and why?

2. Which commercial is the least effective, and why?

3. Overall, are media campaigns effective in keeping people from using drugs? Why?

Alcohol

• Causes approximately 85,000 deaths in U.S. each year (CDC).

• Most abused substance in the country.• DUI accidents primary cause of death among teenagers

in the U.S.• People who drink alcohol more likely to:1. Engage in high-risk sexual behavior2. Use tobacco3. Have poor grades/job performance4. Use illegal drugs

Tobacco

• Nicotine is the active drug in tobacco• Currently 20% of adults smoke, compared to

over 40% in 1965 (CDC, 2007)• According to the CDC (2007), approx 50% of all

high school seniors have tried cigarettes• 90% of all adult smokers started by age 19

(ACS).• Approximately 440,000 people die in the U.S.

from smoking-related causes.

Tobacco, cont.

• 350,000 acres in the U.S. are currently used in tobacco production (MSNBC, 6/11/08)

• Estimated profit from tobacco per acre: $ 1,000-1,500. From corn: $100-150 (MSNBC, ibid)

• #1 cash crop in U.S.: Marijuana (Estimates have been as much as $100 Billion/annually)

Addiction and Dependence

• Physiological Dependence (aka Addiction)Why are some people more prone to addiction than

others?Salience Theory of Addiction (Volkow)- Involves the neurotransmitter dopamine- Dopamine is involved in motivation, pleasure, and

learning- Earlier theories believed that dopamine triggered the

brain’s pleasure centers (e.g. limbic system, prefrontal cortex), causing the addict to seek the next “fix”

• Problem: addicts often are completely miserable (think Jessica from “Intervention”). According to Volkow, some substances and/or behaviors trigger such a rush of dopamine that it overwhelms receptors within the brain.

• Result: The dopamine now acts as a motivating agent, making the need to get the next “fix” the most salient (i.e. important) thing for the addict to accomplish.

• Conclusion: According to this theory, Tiger Woods and Jessica have more in common than you might think