AP Psychology Unit 4/5 Vocab

### Unit 4: Sensation and Perception

1. Sensation - The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.

2. Perception - The process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events.

3. Bottom-Up Processing - Analysis that begins with the sensory receptors and works up to the brain's integration of sensory information.

4. Top-Down Processing - Information processing guided by higher-level mental processes, drawing on our experience and expectations.

5. Selective Attention - The focusing of conscious awareness on a particular stimulus.

6. Inattentional Blindness - Failing to see visible objects when attention is directed elsewhere.

7. Change Blindness - Failing to notice changes in the environment.

8. Transduction - The conversion of one form of energy into another, as in transforming stimulus energies into neural impulses.

9. Psychophysics - The study of relationships between the physical characteristics of stimuli and our psychological experience of them.

10. Absolute Threshold - The minimum stimulus energy needed to detect a particular stimulus 50% of the time.

11. Signal Detection Theory - A theory predicting how and when we detect the presence of a faint stimulus amid background noise.

12. Subliminal - Below one's absolute threshold for conscious awareness.

13. Priming - The activation of certain associations, predisposing perception, memory, or response.

14. Difference Threshold (Just Noticeable Difference) - The minimum difference between two stimuli required for detection 50% of the time.

15. Weber’s Law - Principle that to be perceived as different, two stimuli must differ by a constant percentage.

16. Sensory Adaptation - Diminished sensitivity due to constant stimulation.

17. Perceptual Set - A mental predisposition to perceive one thing and not another.

18. Extrasensory Perception (ESP) - The claim that perception can occur apart from sensory input.

19. Parapsychology - The study of paranormal phenomena, including ESP and psychokinesis.

20. Wavelength - The distance from the peak of one light or sound wave to the next.

21. Hue - The color we experience, determined by the wavelength of light.

22. Intensity - The amount of energy in a light or sound wave, perceived as brightness or loudness.

23. Pupil - The adjustable opening in the center of the eye through which light enters.

24. Iris - The colored part of the eye, a muscle that controls the size of the pupil.

25. Lens - The transparent structure behind the pupil that changes shape to focus images on the retina.

26. Retina - The light-sensitive inner surface of the eye, containing rods and cones and processing visual information.

27. Accommodation - The eye's lens changes shape to focus near or far objects on the retina.

28. Rods - Retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision.

29. Cones - Retinal receptors concentrated near the retina's center and function in daylight or well-lit conditions.

30. Optic Nerve - The nerve that carries neural impulses from the eye to the brain.

31. Blind Spot - The point where the optic nerve leaves the eye, creating a "blind" spot because no receptor cells are located there.

32. Fovea - The central focal point in the retina, around which the eye's cones cluster.

33. Feature Detectors - Nerve cells in the brain that respond to specific features of the stimulus, like shape, angle, or movement.

34. Parallel Processing - The brain's ability to process many aspects of a problem simultaneously.

35. Young-Helmholtz Trichromatic (Three-Color) Theory - Theory that the retina contains three different color receptors (red, green, blue).

36. Opponent-Process Theory - Theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision.

37. Gestalt - An organized whole; gestalt psychologists emphasize our tendency to integrate pieces of information into meaningful wholes.

38. Figure-Ground - The organization of the visual field into objects (figures) that stand out from their surroundings (ground).

39. Grouping - The perceptual tendency to organize stimuli into coherent groups.

40. Depth Perception - The ability to see objects in three dimensions, allowing judgment of distance.

41. Visual Cliff - A laboratory device for testing depth perception in infants and young animals.

42. Binocular Cues - Depth cues that depend on the use of both eyes.

43. Retinal Disparity - A binocular cue for perceiving depth by comparing images from both eyes.

44. Monocular Cues - Depth cues available to either eye alone.

45. Phi Phenomenon - An illusion of movement created when two or more adjacent lights blink on and off.

46. Perceptual Constancy - Perceiving objects as unchanging despite changes in illumination and retinal images.

47. Color Constancy - Perceiving familiar objects as having consistent color, even if lighting alters the wavelengths reflected.

48. Perceptual Adaptation - The ability to adjust to an artificially displaced or inverted visual field.

49. Audition - The sense or act of hearing.

50. Frequency - The number of complete wavelengths that pass a point in a given time, determining pitch.

51. Pitch - A tone's highness or lowness, depending on frequency.

52. Middle Ear - The chamber between the eardrum and cochlea with three tiny bones that concentrate vibrations on the cochlea's oval window.

53. Cochlea - A coiled, fluid-filled tube in the inner ear that triggers nerve impulses in response to sound waves.

54. Inner Ear - The innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.

55. Sensorineural Hearing Loss - Hearing loss caused by damage to the cochlea’s receptor cells or auditory nerves.

56. Conduction Hearing Loss - Hearing loss caused by damage to the mechanical system conducting sound waves to the cochlea.

57. Cochlear Implant - A device converting sounds into electrical signals to stimulate the auditory nerve.

58. Place Theory - Theory linking the pitch we hear with the location where the cochlea’s membrane is stimulated.

59. Frequency Theory - Theory that the brain reads pitch by monitoring the frequency of neural impulses.

60. Gate-Control Theory - Theory that the spinal cord has a gate that blocks or allows pain signals to the brain.

61. Kinesthesia - The system for sensing the position and movement of individual body parts.

62. Vestibular Sense - The sense of body movement and position, including balance.

63. Sensory Interaction - The principle that one sense may influence another.

64. Embodied Cognition - The influence of bodily sensations, gestures, and other states on cognitive preferences and judgments.

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People to Know (Unit 4)

1. Gustav Fechner - Early psychologist who studied the relationship between stimuli and sensation, laying the foundation for psychophysics.

2. Ernst Weber - Known for Weber's Law, which quantifies the perception of changes in stimulus intensity.

3. David Hubel - Discovered feature detectors in the visual cortex.

4. Torsten Wiesel - Collaborated with Hubel on feature detection research.

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### Unit 5: States of Consciousness

1. Consciousness - Our awareness of ourselves and our environment.

2. Hypnosis - A social interaction involving a subject’s openness to suggestions.

3. Posthypnotic Suggestion - A suggestion made during hypnosis to be carried out after the subject is no longer hypnotized.

4. Dissociation - A split in consciousness that allows some thoughts and behaviors to occur simultaneously.

5. Circadian Rhythm - The biological clock regulating bodily rhythms on a 24-hour cycle.

6. REM Sleep - A sleep stage with vivid dreams and relaxed muscles, while other systems are active.

7. Alpha Waves - The slow brain waves of a relaxed, awake state.

8. Sleep - A periodic, natural loss of consciousness.

9. Hallucination - A false sensory experience with no external stimulus.

10. Delta Waves - The large, slow brain waves associated with deep sleep.

11. NREM Sleep - Non-rapid eye movement sleep encompassing all stages except REM.

12. Suprachiasmatic Nucleus (SCN) - A pair of hypothalamic cell clusters controlling circadian rhythm.

13. Insomnia - Recurring problems in falling or staying asleep.

14. Narcolepsy - A disorder causing uncontrollable sleep attacks.

15. Sleep Apnea - A disorder with temporary cessations of breathing and awakenings.

16. Night Terrors - High arousal and appearance of terror during NREM-3 sleep.

17. Dream - A sequence of images, emotions, and thoughts in a sleeping mind.

18. Manifest Content - The remembered storyline of a dream.

19. Latent Content - The hidden meaning of a dream, per Freud.

20. REM Rebound - The tendency for REM sleep to increase after deprivation.

21. **Sub

stance Use Disorder** - Continued substance craving and use despite risks.

22. Psychoactive Drug - A chemical that alters perceptions and moods.

23. Tolerance - Diminished drug effect with regular use.

24. Addiction - Compulsive craving and use of a substance.

25. Withdrawal - Discomfort following the discontinuation of a drug.

26. Depressants - Drugs that reduce neural activity and slow body functions.

27. Alcohol Use Disorder - Prolonged and problematic alcohol use.

28. Barbiturates - Drugs depressing the central nervous system, impairing memory and judgment.

29. Opiates - Drugs that reduce pain and anxiety.

30. Stimulants - Drugs that excite neural activity and increase body functions.

31. Amphetamines - Drugs that stimulate neural activity, causing sped-up functions.

32. Nicotine - A stimulating and highly addictive psychoactive drug in tobacco.

33. Cocaine - A powerful stimulant producing increased alertness and euphoria.

34. Methamphetamine - A highly addictive stimulant that affects dopamine levels.

35. Ecstasy (MDMA) - A stimulant and mild hallucinogen causing euphoria and social intimacy.

36. Hallucinogens - Drugs that distort perceptions and evoke sensory images.

37. LSD - A powerful hallucinogenic drug causing visual distortions.

38. Near-Death Experience - An altered state of consciousness reported after close brushes with death.

39. THC - The major active ingredient in marijuana causing mild hallucinations.

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People to Know (Unit 5)

1. William James - Early psychologist who considered consciousness to be a continuous "stream."

2. Ernest Hilgard - Known for his theory of dissociation in hypnosis.

3. Sigmund Freud - Proposed theories on dreams, particularly manifest and latent content.