AP Psychology: Sensation and Perception - Unit 3

Introduction

• Sensation: Raw data from the five senses; involves sensory receptors.
• Perception: Interpreting sensory information.

Gestalt Psychology

• Principles of perceptual organization.
  • Figure and Ground: Simplifies visual information into figures and background.
  • Continuation: View objects as continuous over time.
  • Closure: Brain fills in gaps in familiar objects.
  • Similarity: Group similar objects together.
  • Proximity: Objects close together perceived as one unit.
  • Symmetry: Symmetrical objects perceived as a single object.

Depth Perception

• Binocular Cues: Require both eyes; include convergence and retinal disparity.
• Monocular Cues: Require one eye; include relative size, interposition, relative height, shading and contour, texture gradient, and linear perspective.
• Motion Parallax: Objects closer appear to move faster.

Sensory Processes

• Sensory Transduction: Conversion of sensory stimuli into neural signals.
• Absolute Threshold: Minimum stimulation needed to detect a stimulus.
• Signal Detection Theory: Predicts detection of weak signals; categories: hit, miss, false alarm, correct rejection.
• Sensory Adaptation vs Habituation:
  • Adaptation: Decreased sensitivity to unchanging stimulus.
  • Habituation: Decreased response to repeated stimulus.

Perception of Change

• Difference Threshold: Minimum difference needed to detect a change.
• Weber-Fechner Law: Difference must be a constant percentage, not amount.

Perceptual Constancy

• Size, Color, Shape, Lightness Constancy: Perception remains constant despite changes.
• Perceptual Sets and Schemas: Influence perception based on prior experiences.
• Optical Illusions: Perception influenced by cultural and experiential factors.

Anatomy of the Eye

• Sclera: Protective layer.
• Cornea: Transparent front; bends light.
• Iris and Pupil: Control light entry.
• Lens: Focuses light.
• Retina: Contains photoreceptors.
• Optic Nerve: Transmits visual information to the brain.
• Rods and Cones: Detect light; rods for dim light, cones for color.

Color Vision

• Trichromatic Theory: Three color receptors (red, blue, green).
• Opponent Process Theory: Color perception through opponent channels.
• Color Blindness: Achromatism, Dichromatism, Trichromatism.
• Synesthesia: Stimulation of one sense triggers another.

Hearing and the Ear

• Outer Ear: Pinna directs sound.
• Middle Ear: OSSICLES amplify sound (malleus, incus, stapes).
• Inner Ear: Includes cochlea for sound transduction.
• Frequency vs Amplitude: Frequency determines pitch; amplitude determines loudness.
• Hearing Loss:
  • Sensorineural: Damage to inner ear.
  • Conductive: Obstruction or damage in the ear canal.

Chemical Senses

• Olfactory System: Smell via olfactory receptors and bulbs.
• Taste System: Taste buds on papillae detect five basic tastes.

Skin and Touch

• Epidermis and Dermis: Layers of skin responsible for protection and sensation.
• Pain Receptors: Detect various stimuli.
• Phantom Limb Sensation: Sensation in amputated limbs.

Kinesthetic and Vestibular Senses

• Proprioceptors: Sensory receptors for body position.
• Vestibular Sense: Balance and head position.

Conclusion

• Sensory Interaction: Senses work together to create a complete perceptual experience.

Review Recommendations

• Complete practice quizzes.
• Use the study guide for more detailed explanations.
• Explore additional resources for deeper understanding.