AP Psychology Unit 3: Sensation and Perception

Introduction

• Sensation vs. Perception
  • Sensation: Raw data from the five senses, received by sensory receptors.
  • Perception: Interpretation of sensory information.

Gestalt Principles

• Perceptual Organization: Whole is greater than individual parts.
• Principles include:
  • Figure and Ground: Simplifying visual information into objects of focus (figure) and background (ground).
  • Continuation: Viewing an object as a whole even when connected to another.
  • Closure: Filling in missing information subconsciously.
  • Similarity: Viewing similar objects as part of a group.
  • Proximity: Closeness of objects perceived as a single image.
  • Symmetry: Symmetrical objects perceived as one object.

Depth Perception

• Binocular Cues: Require two eyes, include convergence and retinal disparity.
• Monocular Cues: Require one eye, include:
  • Relative Size: Closer objects appear larger.
  • Interposition: Obstructed objects appear farther.
  • Relative Height: Higher objects appear farther away.
  • Shading and Contour: Hazier objects are farther.
  • Texture and Gradient: Clear objects are closer.
  • Linear Perspective: Parallel lines converge at a distance.
  • Motion Parallax: Closer objects move faster.

Sensory Processing

• Sensory Transduction: Activation of sensory neurons for sensation.
• Absolute Threshold: Minimum stimulus required for sensation.
• Signal Detection Theory: Predicts perception of weak signals.
• Sensory Adaptation vs. Habituation:
  • Sensory Adaptation: Continuous, unchanging stimulus.
  • Habituation: Repeated exposure to stimulus reduces responsiveness.
• Difference Threshold: Minimum change between stimuli for detection.

Perception Principles

• Perceptual Constancy: Objects remain constant despite changes.
  • Size, Color, Shape, Lightness Constancy.
• Perceptual Sets and Schemas: Influence perception based on experience and expectations.

Visual System

• Eye Anatomy: Sclera, Cornea, Aqueous Humor, Iris, Pupil, Lens, Vitreous Humor, Retina, Choroid, Optic Nerve.
• Rods and Cones: Visual receptors for detail, color, and dim light.
• Astigmatism: Corneal shape affecting focus.
• Cataracts: Cloudy lens causing blurry vision.

Color Perception

• Trichromatic Theory: Color vision from red, green, and blue receptors.
• Opponent Processing Theory: Color information processed in pairs.
• Color Blindness: Types include achromatism and dichromatism.
• Synesthesia: Stimulation of one sense triggers another.

Sound Perception

• Ear Anatomy: Pinna, Auditory Canal, Eardrum, Ossicles (Malleus, Incus, Stapes), Oval Window, Cochlea, Organ of Corti.
• Hearing Loss: Sensorineural vs. Conductive.
• Cochlear Implants and Hearing Aids: Assistive hearing devices.

Chemical Senses: Smell and Taste

• Olfactory System: Olfactory receptors, bulb, and nerve.
• Taste System: Papillae (taste buds) for sweet, salty, sour, bitter, savory.
• Gestation: Sensation of tasting.

Body Senses

• Skin Anatomy: Epidermis, Dermis, Hypodermis.
• Pain Receptors: Detect pain, temperature, pressure.
• Phantom Limb Sensations: Pain in missing body parts.
• Kinesthesis: Perception of body movements.
• Vestibular Sense: Balance and equilibrium.

Conclusion

• Sensory Interaction: Senses influence each other, enhancing perception.

• Action Items:
  • Review the study guide and practice quizzes for a deeper understanding.
  • Check the ultimate review packet for more resources.

As always, ensure you understand these concepts deeply and refer to additional resources if needed. Happy studying!