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.