Chapter 4: Sensation and Perception Psychology in Action (8e) by Karen Huffman PowerPoint  Lecture Notes Presentation Chapter 4: Sensation and Perception Karen Huffman, Palomar College ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Lecture Overview Introduction to Sensation & Perception Understanding Sensation How We See and Hear Our Other Senses Understanding Perception ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Introduction to Sensation and Perception Sensation (process of receiving, converting, and transmitting raw sensory information from the external and internal environments to the brain) Perception (process of selecting, organizing, and interpreting sensory information) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Sensation Versus Perception When you stare at the cube on the left, which area is the top, bottom, or back? In the figure on the right, is this a young woman looking to the right, or an older woman with her chin buried in her jacket? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Sensation Vs. Perception ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Sensation: Processing Processing (sensory organs contain receptors that receive sensory information from the environment) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Sensation: Processing Three Types of Processing: Transduction converts the sensory stimuli into neural impulses that are sent on to the brain. Sensory reduction filters and analyzes incoming sensations before sending on to the brain. Coding converts particular sensory input into a specific sensation sent to parts of the brain. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Sensation: Processing (Continued) Transduction, sensory reduction, and coding all occur at the sensory level and messages are then sent on to the brain. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Sensation: Thresholds Psychophysics: Testing limits and changes Absolute Threshold: smallest amount of a stimulus we can detect Difference Threshold: minimal difference needed to detect a a stimulus change; also called the just noticeable difference (JND) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Sensation: Thresholds Sensory Adaptation: decreased sensory response to continuous stimulation ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) How We See VISION- How We See Light is a form of electromagnetic energy that moves in waves. Many types of electromagnetic waves form the electromagnetic spectrum. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

How We See: Electromagnetic Spectrum ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

How We See: Electromagnetic Spectrum The flower on the left looks normal to us, whereas the one on the right was photographed under ultraviolet light. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) How We See: Light Waves Light waves vary in: length (wavelength), which determines frequency (hue or color). height (amplitude), which determines brightness or intensity. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

How We See: Anatomy of the Eye The function of the eye is to capture light waves and focus them on receptors at the back of the eyeball. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

How We See: Structures of the Retina Receptors for vision are the rods and cones located in the retina. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Do You Have a Blind Spot? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

How We See: Are You Nearsighted or Farsighted? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) How We Hear: Audition Sound results from movement of air molecules in a particular wave pattern. Sound waves vary in: length (wavelength), which determines pitch (highness or lowness). height (amplitude), which determines loudness (intensity of the sound). ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) How We Hear: Audition The loudness of a sound is measured in decibels. Constant noise above 90 decibels can cause permanent nerve damage to the ear. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

How We Hear: Anatomy of the Ear Receptors for hearing are hair cells located in the cochlea. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Our Other Senses Our sense of smell is called olfaction. Receptors for smell are embedded in a nasal membrane, the olfactory epithelium. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Our Other Senses: Gustation (Sense of Taste) Receptors for gustation are taste buds, located in the papillae on the surface of the tongue. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Our Other Senses: Three Body Senses Skin senses involve three basic skin sensations- touch (or pressure), temperature, and pain. Receptors for these sensations occur in various concentrations and depths in the skin. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Our Other Senses: Three Body Senses Vestibular sense (or sense of balance) involves the vestibular sacs and semicircular canals located in the inner ear. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Three Body Senses (Continued) Kinesthesia provides the brain with information about bodily posture and bodily movement. Kinesthetic receptors are found throughout the muscles, joints, and tendons of the body. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Perception Illusions: false or misleading perceptions help scientists study the processes of perception (e.g., the horizontal-vertical illusion) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: The Muller-Lyer Illusion Which vertical line is longer? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Perception Do You See the Cow? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Perception Now Can You See the Cow? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Perception (Continued) Perception’s three basic processes: Selection Organization Interpretation ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Perception: Selection Selection (choosing where to direct attention) involves three factors: Selective Attention (filtering out and attending only to important sensory messages) Feature Detectors (specialized neurons respond only to certain sensory information) Habituation (brain’s tendency to ignore environmental factors that remain constant) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Perception: Selection Kittens raised with only vertical visual stimuli fail to develop the ability to detect horizontal lines. Can you explain why? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Perception: Organization Organization: assembling of information into patterns that help us understand the world We organize sensory information in terms of: Form Constancy Depth Color ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Perception: Organization Form Perception Gestalt psychologists developed laws explaining how people perceive form according to: Figure and ground Proximity Continuity Closure Similarity ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Form Perception- Basic Gestalt Principles Understanding Perception: Organization Form Perception- Basic Gestalt Principles ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Form Perception: Can You Explain These Impossible Figures? Understanding Perception: Organization Form Perception: Can You Explain These Impossible Figures? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Organization Perceptual Constancy: Tendency to perceive the environment as remaining the same even with changes in sensory input. Four best-known constancies: Size Shape Color Brightness ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Can You Identify the Size, Shape, Color, and Brightness Constancies? Understanding Perception: Organization Can You Identify the Size, Shape, Color, and Brightness Constancies? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Organization-- The Ames Room Illusion ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Organization Depth Perception: ability to perceive three dimensional space and accurately judge distance ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Organization Depth Perception (Continued) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Organization Depth Perception involves both binocular (two eyes) and monocular (one eye) cues. Two Binocular Cues for Depth: Retinal disparity (separation of the eyes causes different images to fall on each retina) Convergence (the closer the object the more the eyes turn inward) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Binocular Cues- Retinal Disparity (left) Convergence (right) Understanding Perception: Organization Binocular Cues- Retinal Disparity (left) Convergence (right) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Organization Six Monocular Depth Cues: Can You Find Them? linear perspective interposition relative size texture gradient aerial perspective light and shadow ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Organization Color Perception is a combination of two theories: Trichromatic: color perception results from mixing three distinct color systems (red, green, and blue) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Organization Color Perception is a combination of two theories: Opponent-process: color perception results from three systems of color opposites (blue-yellow, red-green, and black-white) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Organization People who have red-green color deficiency have trouble perceiving the green colored number in the center of this circle. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Organization and Color Perception ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Understanding Perception: Four Factors in Interpretation Interpretation (how we explain sensations) involves four major factors: Perceptual adaptation (brain adapts to changed environments) ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Four Factors in Interpretation Perceptual set: readiness to perceive in a particular manner, based on expectations Some groups are more likely than others to be affected by the center item in this collection. Can you explain why? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Four Factors in Interpretation Another example of perceptual set. Do you notice anything wrong with these photos? ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e) Understanding Perception: Four Factors in Interpretation Frame of reference: based on the context of the situation Bottom-up or top-down processing: information either starts with raw sensory data or with thoughts, expectations, and knowledge ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Problems with Believing in Subliminal Perception and ESP Subliminal perception may occur, but there is little or no evidence of subliminal persuasion. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Problems with Believing in Subliminal Perception and ESP Extrasensory perception (ESP): supposed ability to perceive things that go beyond the five normal senses ESP research is criticized due to lack of experimental control and replicability. ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)

Sensation and Perception Psychology in Action (8e) by Karen Huffman PowerPoint  Lecture Notes Presentation End of Chapter 4: Sensation and Perception Karen Huffman, Palomar College ©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)