CHAPTER 6 / 7

Perceptions

  • Selective attention means our awareness focuses on only a limited aspect of all that we can experience.
  • Illusions mislead us by playing on the ways we typically organize and interpret our sensations.
  • Depth perception is the ability to see objects in three dimensions although the images that strike the eye are two-dimensional. It enables us to judge distance.
  • Binocular cues (depth cues) require information from both eyes.
  • Monocular cues enable us to judge depth using information from only one eye.
  • Our basic assumption is that shrinking objects are retreating and enlarging objects are approaching.
  • Perceptual constancy is necessary to recognize an object. It enables us to see an object as unchanging.
ESP
  • Parapsychologists state that there are three varieties of extrasensory perception (ESP):

-telepathy (mind-to-mind communication),

-clairvoyance (perceiving remote events), and

-precognition (perceiving future events).

Closely linked with these are claims of psychokinesis, or “mind over matter.”

  • Research psychologists remain skeptical because the acts of so-called psychics have typically turned out to be nothing more than the illusions of stage magicians.
  • An important reason for their skepticism, however, is the absence of a reproducible ESP result (i.e. results haven’t been proven in experiments). In addition, to believe in ESP, one must believe that the brain is capable of perceiving without sensory input.

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Consciousness

  • Psychology began as the study of consciousness, our awareness of ourselves, and of our environment.
  • Conscious information processing allows us to exert voluntary control and to communicate our mental states to others.
  • Beneath the surface, faster unconscious processing occurs simultaneously on many parallel tracks. For example, when we meet someone, we instantly and unconsciously react to gender, race, and appearance, and then become aware of our response.
  • Our daily schedule of waking and sleeping is governed by a biological clock known as circadian rhythm.
  • We pass through a cycle of five sleep stages that total about 90 minutes.
  • People differ in their individual sleep requirements. For example, newborns sleep twice as much as adults.
  • Children are more prone to sleepwalking and sleep talking—conditions which run in families.
  • Our dreams are mostly of ordinary events; they often relate to everyday experiences and more frequently involve anxiety or misfortune than triumphant achievement.
  • Hypnosis does not enhance recall of forgotten events and may even foster false memories.
  • Research indicates that hypnotized people cannot be made to act against their will and that hypnosis can be at least temporarily therapeutic.

Drugs and Alcohol

  • Psychoactive drugs include the depressants, stimulants, and hallucinogens. All of these drugs operate at the brain’s synapses by stimulating, inhibiting, or mimicking the activity of neurotransmitters, the brain’s chemical messengers.
  • Depressants such as alcohol, the barbiturates, and the opiates act by reducing neural activity and slowing body functions.
  • Alcohol is a disinhibitor. It also impairs judgment, reduces self-awareness, and disrupts memory processes by suppressing REM sleep.
  • Stimulants, such as caffeine, nicotine, amphetamines, cocaine, Ecstasy, and methamphetamine, excite neural activity and arouse body functions.
  • Marijuana’s main active ingredient, THC, produces a variety of effects, including disinhibition, a euphoric high, feelings of relaxation, relief from pain; and intense sensitivity to colors, sounds, tastes, and smells.
Near Death Experiences
  • A number of those who have survived a brush with death later recall near-death experiences. These experiences are marked by out-of-body sensations, visions of tunnels and bright lights, and intense feelings of joy, love, and peace.

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