AP Psych Unit 3 Notes Myers 3rd
Module 22: Vision: Sensory and Perceptual Processing
Learning Targets
22-1: Discuss the characteristics of the energy that we see as visible light, and describe the structures in the eye that help focus that energy.
22-2: Describe how the rods and cones process information, and explain the path information travels from the eye to the brain.
22-3: Discuss how we perceive color in the world around us.
22-4: Describe the location and function of feature detectors.
22-5: Explain how the brain uses parallel processing to construct visual perceptions.
Light Energy and Eye Structures
22-1: Characteristics of Visible Light and Eye Structures
The eye receives light energy and transduces it into neural messages, creating what we consciously see.
The light stimuli that strike the eyes are not particles of color, but pulses of electromagnetic energy perceived as color.
Electromagnetic Spectrum: Visible light is a narrow bandwidth within the full spectrum that ranges from gamma rays to radio waves.
Wavelength: The distance between wave peaks; shorter wavelengths are associated with bluish colors, longer ones with reddish colors.
Amplitude: The height of the wave; determines brightness (intensity of light).
Eye Structure:
Cornea: The transparent outer layer that bends light.
Pupil: An adjustable opening controlled by the iris that regulates light entry.
Iris: The colored muscle that adjusts pupil size according to light intensity and emotional states.
Lens: A transparent structure that focuses light onto the retina through a process called accommodation.
Retina: A multilayered tissue containing receptor cells (rods and cones) that convert light energy into neural impulses.
22-2: Rods and Cones Processing Information
Pathway of Light Processing:
Light triggers chemical reactions in rods and cones, starting at the back of the retina and leading to neural signals in bipolar cells.
Bipolar cells activate ganglion cells whose axons form the optic nerve.
After passing through the thalamus, information travels to the visual cortex in the occipital lobe.
Rods vs. Cones:
Rods: 120 million, responsive to black, white, and gray; critical for peripheral and twilight vision.
Cones: 6 million, concentrated near the fovea; responsible for color and fine detail in well-lit conditions.
Blind Spot: The area where the optic nerve exits the eye, devoid of receptor cells, leading to a gap in visual perception which the brain fills in.
22-3: Perception of Color
Color perception is not an intrinsic property of objects but a mental creation from the brain processing light wavelengths.
Trichromatic Theory: The retina contains three types of color receptors sensitive to red, green, and blue, which combine to produce other colors.
Opponent Process Theory: Suggests ability to see colors based on opposing retinal processes (red-green, blue-yellow).
Color Blindness: Male color blindness is often linked to genetic factors affecting the cones responsible for color detection.
22-4: Feature Detectors
Location and Function: Feature detectors in the brain's visual cortex respond to specific elements such as edges, lines, and angles, relaying information to other cortical areas for complex pattern recognition.
Supercell Clusters: Integrate responses from multiple feature detectors for recognition of complex stimuli, such as faces.
22-5: Parallel Processing in Visual Perception
Parallel Processing: The brain divides a visual scene into distinct sub-dimensions like color, motion, form, and depth, processing each aspect simultaneously.
This allows for the integrated perception and binding of information, creating an instant and coherent visual experience.
Module 23: Visual Organization and Interpretation
Learning Targets
23-1 Describe the Gestalt psychologists' understanding of perceptual organization and how principles like figure-ground and grouping affect perception.
23-2 Explain binocular and monocular cues for perceiving depth and motion.
23-3 Explain perceptual constancies and their role in meaningful perception.
23-4 Discuss the impact of experience on perception through restored vision and sensory restriction.
23-1: Gestalt Psychology and Perception
Gestalt Principles: Humans instinctively organize sensory experiences into wholes (gestalts) rather than just collections of separate parts.
Key Principles:
Figure-Ground: The ability to distinguish a figure from its background.
Grouping: Organizing stimuli into coherent groups based on principles such as proximity, continuity, and closure.
23-2: Depth Perception and Motion
Depth Perception: The ability to view the world in three dimensions and judge distances, developed through binocular (retinal disparity, convergence) and monocular cues (relative size, interposition).
Motion Perception: Involves understanding the movement based on the relation of objects as they move closer or farther away.
23-3: Perceptual Constancies
Perceptual Constancy: Our ability to perceive familiar objects as unchanging despite varying conditions such as color, shape, and size, maintaining recognition under differing contexts.
23-4: Impact of Experience on Perception
Research on restored vision suggests that visual recognition is heavily dependent on early experiences, as seen in individuals who regain vision after early blindness.
Module 24: Hearing
Learning Targets
24-1 Describe characteristics of sound as air pressure waves.
24-2 Explain how the ear transforms sound energy into neural messages.
24-3 Discuss loudness detection, pitch discrimination, and sound localization.
24-1: Sound Waves Characteristics
Sound is perceived as waves of varying amplitude and frequency:
Amplitude affects loudness (measured in decibels).
Frequency determines pitch (highs and lows).
24-2: Ear Transformation Process
**Process of Hearing:
Sound waves hit the eardrum causing it to vibrate.
Vibrations are transmitted by tiny bones in the middle ear (hammer, anvil, stirrup) to the cochlea.
Within the cochlea, vibrations induce fluid movement, bending hair cells in the basilar membrane which triggers neural impulses.
Impulses are sent via the auditory nerve to the brain's auditory cortex.
24-3: Detecting Pitch and Locating Sounds
Loudness is determined by the number of active hair cells responding to sound waves.
Pitch perception combines place theory (localizes pitch based on cochlear stimulation) and frequency theory (rate of neural impulses correlates with sound frequency).
Sound localization is made possible by detecting differences in time and intensity between signals reaching both ears.
Module 25: The Other Senses
Learning Targets
25-1 Describe the sense of touch.
25-2 Discuss biological, psychological, and social-cultural influences on pain.
25-3 Compare and contrast the senses of taste and smell.
25-4 Explain body position and movement perception.
25-5 Explore sensory interaction and embodied cognition.
25-1: Sense of Touch
Touch encompasses multiple sensations: pressure, warmth, cold, pain combining to create a textured experience like hot or ticklish sensations.
25-2: Pain Perception Influences
Pain perception is constructed through interactions among biological (nociceptors), psychological (attention) factors, and social contexts, influenced by the gate-control theory. Placebos and distractions serve to alleviate pain perception.
25-3: Taste vs. Smell
Both senses are chemical; taste involves five basic tastes (sweet, sour, salty, bitter, umami), while smell involves a complex combination of receptors responding to odor molecules.
25-4: Body Position and Movement
Kinesthesia helps us sense limb positions while the vestibular system monitors balance and orientation through fluid movement in the semicircular canals.
25-5: Sensory Interaction and Embodied Cognition
Our senses work together; for example, smell enhances taste. Embodied cognition shows that body sensations can influence cognitive judgments and preferences. Undeniably, sensory interactions inform perceptions of the environment and personal experience.