Untitled Quiz

Unit 2: Sensation and Perception

• Learning Objectives: Students will be able to differentiate between sensation and perception, explain the nature of perception, and its scope, explain the process of perception, identify factors affecting perception, describe laws of perceptual organization, summarize common types of perceptual constancies, and explain the basis of perceptual illusion.

Sensation

• Definition: The process through which our sensory organs receive and transmit information about our environment.
• Components: Involves sensory organs, presence of stimulus in the environment, converting physical energy into electrical impulses, and transmitting these impulses to the brain for processing.
• Transduction: The process of translating physical energy into electrical impulses by receptors.

Our Senses

• Vision: Light enters the eye, is focused on retina, and then converted to electrical impulses.
• Visual Acuity: The ability to accurately distinguish details in the visual field.
• Blind Spot: A point on the retina where there are no receptor cells for vision.
• Hearing: Sound waves affect the eardrum, which then stimulates nerve cells.
• Smell: Specialized receptor cells to detect chemical substances in the air.
• Taste: Sensory cells react to chemicals in food, leading to different taste sensations (sweet, sour, salty, bitter).
• Skin Senses: Receptors in the skin that detect pressure, warmth, cold, and pain..
• Kinesthetic Sense: Knowledge of the position of the body parts relative to each other.

Perception

• Definition: The process by which we organize and interpret sensory information to understand the world around us.
• Stages: Selection, organization, and interpretation. Involves how we filter info, how we put that info into meaningful patterns, and how we make sense of that.

Theoretical Approaches to Perception

• Top-down: Existing knowledge and experiences influence how we interpret stimuli.
• Bottom-up: Stimuli themselves drive the perception.

Laws of Perceptual Organization: Gestalt Principles

• Figure-ground: The tendency to segment the visual field into distinct objects (figure) and surrounding areas (ground).
• Proximity: The tendency to group together objects that are near each other.
• Similarity: The tendency to group together objects that are similar in appearance.
• Closure: The tendency to complete incomplete figures.
• Continuity: The tendency to perceive continuous figures.
• Common Fate: The tendency to perceive objects moving in the same direction as a group.
• Symmetry: The tendency to perceive symmetrical images as a whole.

Factors Affecting Perception

• Motivation: Needs, desires, and expectations influence what we perceive.
• Expectation: Readiness to see something in a particular way.
• Emotions: Feelings impact how we perceive stimuli.
• Stimulus Characteristics: The intensity, size, or appearance of a stimulus can influence what we pay attention to and perceive.
• Culture: Cultural background can affect perception.
• Experience: Past experiences shape how we perceive things.

Perception of Depth and Distance

• Monocular Cues: Depth cues that require only one eye (relative size, texture gradient, aerial perspective).
• Binocular Cues: Depth cues that require two eyes (retinal disparity, convergence).

Movement Perception

• Methods: Retinal motion, motion aftereffect (MAE), induced movement.

Errors in Perception: Illusions

• Examples: Muller-Lyer, Ponzo, Ebbinghaus, Ames room, and Moon illusions.

Key Terms

• Sensation : The process of receiving sensory information
• Perception: The process of interpreting this sensory information.