Chapter 4 AP Psych

1. Sensation

• The process by which sensory receptors detect physical energy from the environment and convert it into neural signals.

• Involves five main senses: vision, hearing, touch, taste, and smell.

2. Perception

• The interpretation and organization of sensory information into meaningful experiences.

• Heavily influenced by experience, expectations, and context.

3. Visual Agnosia

• A neurological condition where a person can see objects but cannot recognize or interpret them.

• Caused by damage to the occipital or temporal lobes.

4. Light & Physical Properties

• Wavelength: Determines color.

• Amplitude: Determines brightness.

• Purity: Determines saturation.

5. Transduction

• The conversion of physical stimuli (e.g., light, sound) into neural signals.

• Occurs in sensory organs like the retina (vision) or cochlea (hearing).

6. Parts of the Eye

• Cornea: Protective outer layer; helps focus light.

• Pupil: Adjustable opening that controls light entry.

• Iris: Colored muscle controlling pupil size.

• Lens: Adjusts shape to focus light onto the retina.

• Retina: Contains photoreceptors (rods and cones) for processing light.

• Fovea: Central point of focus; high concentration of cones.

• Optic Nerve: Transmits visual information to the brain.

• Optic Disk (Blind Spot): Area where the optic nerve exits; no photoreceptors.

7. Lens Accommodation

• The lens changes shape to focus on objects at varying distances.

• Thicker for nearby objects, thinner for distant objects.

8. Nearsightedness

• Difficulty seeing distant objects.

• Light focuses in front of the retina.

9. Farsightedness

• Difficulty seeing nearby objects.

• Light focuses behind the retina.

10. Visual Receptor Cells

• Rods: Detect black, white, and gray; important for peripheral and night vision.

• Cones: Detect color and fine detail; function best in bright light.

11. Ganglion Cells

• Collect visual information from bipolar cells and transmit it to the brain via the optic nerve.

12. Dark & Light Adaptation

• Dark Adaptation: Increased sensitivity to light in low-light conditions.

• Light Adaptation: Decreased sensitivity to light in bright conditions.

13. Trichromatic Theory of Color

• Proposes three types of cones: red, green, and blue.

• Colors are perceived by combining activity from these cones.

14. Color Blindness

• Dichromatism: Missing one type of cone (e.g., red-green color blindness).

• Monochromatism: Missing two or all cone types; no color perception.

15. Opponent Processing Theory

• Suggests color perception depends on opposing pairs: red-green, blue-yellow, black-white.

• Explains phenomena like afterimages.

16. Perceptual Set

• A mental predisposition to perceive things in a certain way, influenced by expectations and context.

17. Feature Analysis

• Detecting specific elements of visual input (e.g., lines, edges) and assembling them into a complex form.

18. Top-Down Processing

• Interpretation guided by higher-level mental processes and prior knowledge.

19. Bottom-Up Processing

• Interpretation starting with sensory input and building up to perception.

20. Apparent Motion (Phi Phenomenon)

• Perception of movement created by successive images or lights flashing in sequence.

21. Gestalt Principles

• Rules of perception for organizing sensory input:

  • Figure-Ground: Distinguishing object from background.

  • Proximity: Grouping nearby elements.

  • Closure: Filling in gaps to complete a figure.

  • Similarity: Grouping similar elements.

  • Simplicity: Preferring simplest explanations.

  • Continuity: Perceiving smooth, continuous patterns.

22. Depth Perception

• Ability to judge distance and spatial relationships.

• Combines binocular and monocular cues.

23. Binocular Depth Cues

• Retinal Disparity: Difference between images in each eye; greater disparity means closer objects.

• Convergence: Eye muscles turning inward for nearby objects.

24. Monocular Depth Cues

• Linear Perspective: Parallel lines converging in the distance.

• Texture Gradient: Finer texture indicates distance.

• Interposition: Closer objects block further ones.

• Relative Clarity: Clearer objects seem closer.

• Relative Size: Larger objects appear closer.

25. Perceptual Constancy

• Recognizing objects as unchanging despite changes in appearance (e.g., size, shape, color).

26. Physical Properties of Sound Waves

• Frequency: Determines pitch.

• Amplitude: Determines volume.

• Purity: Determines timbre.

27. Volley Theory

• Groups of auditory neurons fire in rapid succession to encode high frequencies.

28. Inner Ear

• Cochlea: Spiral-shaped structure with hair cells (auditory receptors) for transduction.

29. Pitch Theories

• Place Theory: Different frequencies activate specific areas of the cochlea.

• Frequency Theory: Frequency of auditory nerve impulses corresponds to sound frequency.

30. Sound Localization

• Determining sound origin based on differences in timing and intensity between ears.

31. Sensorineural Deafness

• Damage to cochlea or auditory nerve; irreversible.

32. Conduction Deafness

• Damage to outer/middle ear structures; often treatable.

33. Vestibular Sense

• Sense of balance and spatial orientation; relies on semicircular canals.

34. Taste (Gustatory System)

• Taste buds detect five primary tastes: sweet, sour, salty, bitter, umami; possibly oleogustus (fat).

35. Tasters

• Supertasters: Highly sensitive to taste.

• Medium Tasters: Average sensitivity.

• Nontasters: Low sensitivity.

36. Sensory Adaptation

• Diminished sensitivity to constant stimuli over time.

37. Olfactory System

• Olfactory Cilia: Detect odor molecules.

• Olfactory Bulb: Processes smell information in the brain.

38. Tactile System (Touch)

• Skin receptors detect pressure, warmth, cold, and pain.

39. Gate-Control Theory

• Pain signals are modulated by spinal "gates" that can block or allow signals to pass to the brain.

40. Schema

• Mental frameworks organizing knowledge and expectations.

41. Sensory Interaction

• When senses influence each other (e.g., smell enhancing taste).

42. Absolute Threshold

• Minimum stimulation needed to detect a stimulus 50% of the time.

43. Just Noticeable Difference (JND)

• Smallest difference detectable between two stimuli.

44. Signal Detection Theory

• Perception of stimuli depends on sensitivity and decision-making criteria.

45. Weber’s Law

• Ernst Weber's principle: JND is a constant proportion of the original stimulus.

46. Pheromones

• Chemical signals affecting behavior or physiology of others, often subconsciously.

47. Synesthesia

• Neurological condition where stimulation of one sense triggers perception in another.

48. Kinesthetic Sense

• Awareness of body position and movement.

49. Selective Attention

• Focusing on one stimulus while ignoring others.

50. Cocktail Party Phenomenon

• Ability to focus on one conversation in a noisy environment, yet notice personal information (e.g., your name).

51. Change Blindness

• Failure to notice changes in a visual scene.

52. Inattentional Blindness

• Failure to notice an unexpected stimulus when attention is focused elsewhere.

53. Afterimage

• Visual sensation persisting after the original stimulus is removed.

54. Prosopagnosia

• "Face blindness"; inability to recognize faces.

55. Blindsight

• Ability to respond to visual stimuli without conscious awareness.

56. Phantom Limb Syndrome

• Sensation of a limb still being present after amputation, often accompanied by pain.