Psych chapter 10

How does dreaming differ from other thinking?

Dreaming resembles other thinking, but it occurs during a time of decreased sensory input and loss of voluntary control of thinking.

How did researchers arrange for a stimulus to be conscious on some trials and not others?

Researchers presented a word for a small fraction of a second. When they simply presented the word, most peo- ple identified it. In other cases, researchers put interfering patterns before and after the word. In those cases, people were not conscious of it.

If you are an evening person, what could you do to improve your grades?

Try to schedule your important classes in the afternoon instead of the morning.

REM behavior disorder (RBD)

a rare disorder in which the mechanism that blocks the movement of the voluntary muscles fails, allowing the person to thrash around and even get up and act out nightmares

sleep apnea

a sleep disorder characterized by temporary cessations of breathing during sleep and repeated momentary awakenings. Many people have occasional brief periods without breathing while asleep. Fail to breathe for a minute or more and then wake up gasping for breath.

polysomnograph

combine an EEG measure with a simultaneous measure of eye movements to produce

minimally conscious state

one stage higher than a vegetative state marked by occasional brief periods of purposeful action and limited speech comprehension

flash suppression

procedure of making a stationary object impossible to see consciously by surrounding it with flashing objects

periodic limb movement disorder

prolonged "creepy-crawly" sensations in their legs, accompa- nied by repetitive leg movements strong enough to awaken the person, especially during the first half of the night

circadian rhythm

the biological clock; regular bodily rhythms (for example, of temperature and wakefulness) that occur on a 24-hour cycle. A rhythm of activity and inactivity lasting about a day

consciousness

the subjective experience of perceiving oneself and one's surroundings

Benjamin Libet

(1916 - 2007) Neuroscientist who conducted experiments that seemed to demonstrate that a build-up of electrical activity precedes the moment-of-decision; suggesting that the conscious decision is not the originator of the action, but that it originates in an unconscious impulse that 'causes' the conscious choice.

What evidence suggests that we construct a conscious perception of a stimulus afterward in- stead of simultaneously with it?

A brief masked stimulus is not perceived consciously, but a slightly longer one is perceived as lasting the entire dura- tion. Also, the perception of a first stimulus can be altered by a stimulus that follows it.

Melatonin

A hormone manufactured by the pineal gland that produces sleepiness.

What evidence shows that déjà vu does not always indicate that an experience was actually familiar?

A person with temporal lobe epilepsy reported an intense déjà vu experience immediately before his seizures, regardless of where he was or what he was seeing at the time.

Narcolepsy

A sleep disorder characterized by uncontrollable sleep attacks. The sufferer may lapse directly into REM sleep, often at inopportune times.

What experience reflects the fact that part of the brain can be awake while another is asleep?

Any of the following: waking up but finding oneself unable to move, sleepwalking, or lucid dreaming.

insomnia

Difficulty in falling asleep or staying asleep. is not enough sleep for the person to feel rested the next day.

paradoxical sleep or rapid eye movement (REM) sleep

During this stage of sleep, the sleeper's eyes move rapidly back and forth under the closed lids.

What was the order of these events: conscious decision to move, brain activity relevant to movement, and the movement itself?

Measurable brain activity came first, then the perception of the conscious decision, and then the movement.

What do people perceive during binocular rivalry?

Most people perceive one stimulus and then the other, alternating.

Are Freud's ideas on dreaming falsifiable in the sense described in Chapter 2?

No. A falsifiable theory makes specific predictions so that we could imagine evidence that would contradict it. Freud's dream theories make no clear predictions.

In the experiment described in the "What's the Evidence?" section, what did participants report, and when did they report it?

Participants watched a special fast clock and noted the time when they made a spontaneous decision to flex the wrist. They reported it a few seconds later.

Name two important functions of sleep.

Sleep conserves energy, and memories strengthen during sleep.

During which sleep stage is the brain least active? During which stage are the muscles least active?

The brain is least active during stage 4 sleep. The mus- cles are least active during REM sleep.

Can hypnosis cause people to do anything they would be unwilling to do otherwise?

The evidence is unclear. In certain experiments, hypno- tized people have done some strange things, but so have nonhypnotized people.

readiness potential

The increased motor cortex activity prior to the start of the movement

Libet's experiment indicated that the brain activity responsible for a movement began earlier than the conscious decision to make the movement. What is the main reason to be uncertain of this conclusion?

We have reasons to doubt that people can accurately state the time that a conscious decision began. Spontaneous movements and the decisions behind them develop gradually, not suddenly.

How is the content of dreams similar to waking thoughts, and how is it different?

We mostly dream about the same topics we think about, but dreams usually feature less happy emotions.

Suppose someone with intact retinas becomes blind because of damage to the visual cortex. Will that person nevertheless synchronize the circadian rhythm to the time of sunlight? Explain

Yes, someone with blindness because of cortical damage nevertheless tends to waken during times of sunlight. The average amount of bright light activates certain ganglion cells that send their output not to the visual cortex, but to the suprachiasmatic nucleus, which controls the circadian rhythm.

Suppose you are the president of a U.S. company, negotiating a business deal with someone from the opposite side of the world. Should you prefer a meeting place in Europe or on an island in the Pacific Ocean?

You should prefer to meet on a Pacific island so that you will travel west.

If you were on a submarine deep in the ocean with only artificial light that was the same at all times, what would happen to your rhythm of wakefulness and sleepiness?

You would continue to produce a 24-hour circadian rhythm. The sun resets the rhythm, but you generate it within your own body

backward masking

a brief visual stimulus after another brief visual stimulus that leads to failure to remember the first

Hypnosis

a condition of focused attention and increased suggestibility that occurs in the context of a special hypnotist-subject relationship

déjà vu experience

a feeling that an event is uncannily familiar

suprachiasmatic nucleus (SCN)

a pair of cell clusters in the hypothalamus that controls circadian rhythm. In response to light, the SCN causes the pineal gland to adjust melatonin production, thus modifying our feelings of sleepiness

jet lag

a period of discomfort and inefficiency while your internal clock is out of phase with your new surroundings

posthypnotic suggestion

a suggestion, made during a hypnosis session, to be carried out after the subject is no longer hypnotized; used by some clinicians to help control undesired symptoms and behaviors

Meditation

a systematic procedure for inducing a calm, relaxed state through the use of special techniques

masking

a word or other stimulus appears on the screen for a fraction of a second, preceded and/or followed by an interfering stimulus. if the interfering stimulus follows it

binocular rivalry

alternation between seeing the pattern in the left retina and the pattern in the right retina

coma

caused by traumatic brain damage, the brain shows a steady but low level of activity and no response to any stimulus

night terror

causes someone to awaken screaming and sweating with a racing heart rate, sometimes flailing with the arms and pounding the walls

activation-synthesis theory of dreams

dreams occur because the cortex takes the haphazard activity that occurs during REM sleep plus whatever stimuli strike the sense organs and does its best to make sense of this activity

Name two practical applications of hypnosis.

hypnosis can relieve pain, and posthypnotic suggestions help some people break unwanted habits, such as smoking

vegetative state

marked by limited responsiveness, such as increased heart rate in response to pain

electroencephalograph (EEG)

measures and amplifies tiny electrical changes on the scalp that reflect patterns measures and amplifies tiny electrical changes on the scalp that reflect patterns

sleep spindles

short bursts of brain waves detected in stage 2 sleep. Waves of activity at about 12 to 14 per second that result from an exchange of information between the cerebral cortex and the underlying thalamus.

basal ganglia

structures in the forebrain that help to control movement

brain death

the brain shows no activity and no response to any stimulus

manifest content

the content that appears on the surface

latent content

the hidden ideas that the dream experience represents symbolically.