Sensation & Perception Flashcards
Define Sensation
The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.
Define Perception
The process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events.
Define Bottom-Up Processing
Analysis that begins with the sensory receptors and works up to the brain’s integration of sensory information.
Define Top-Down Processing
Information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations.
Define Selective Attention
The focusing of conscious awareness on a particular stimulus. You only consciously process a small amount of what your senses take in.
Define Inattentional Blindness
Failing to see visible objects when our attention is directed elsewhere.
Define Change Blindness
Failing to notice changes in the environment.
Define Transduction
Conversion of one form of energy into another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret.
Define Psychophysics
The study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them.
Define Absolute Threshold
The minimum stimulation needed to detect a particular stimulus 50 percent of the time.
Define Signal Detection Theory
A theory that predicts how and when we detect the presence of a faint stimulus amid background stimulation. Assumes that there is no single absolute threshold and that detection depends partly on a person’s experience, expectations, motivation, and alertness.
Define Subliminal
Below one’s absolute threshold for conscious awareness.
Define Priming
The activation, often unconsciously, of certain associations, thus predisposing one’s perception, memory, or response.
Define Difference Threshold
The minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference. The difference threshold increases with the size of the stimulus.
Define Weber’s Law
The principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage, not a constant amount. The exact proportion varies depending on the stimulus.
Define Sensory Adaptation
Diminished sensitivity as a consequence of constant stimulation. Offers the benefit of freedom to focus on informative changes in our environment.
Define Perceptual Set
A mental predisposition to perceive one thing and not another that can influence what we hear, taste, feel, and see.
Define Extrasensory Perception
The controversial claim that perception can occur apart from sensory input.
Define Parapsychology
The study of paranormal phenomena, including ESP and psychokinesis.
Define Wavelength
The distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short blips of cosmic rays to the long pulses of radio transmission.
Define Hue
The dimension of color that is determined by the wavelength of light. What we know as the color names.
Define Intensity
The amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave’s amplitude.
Define Pupil
The adjustable opening in the center of the eye through which light enters.
Define Iris
A ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening.
Define Lens
The transparent structure behind the pupil that changes shape to help focus images on the retina.
Define Retina
The light-sensitive inner surface of the eye, containing the receptor rods and cones puls layers of neurons that begin the processing of visual information.
Define Accommodation
The process by which the eye’s lens changes shape to focus near or far objects on the retina.
Define Rods
Retinal receptors that detect black, white, and grey. Necessary for peripheral and twilight vision, when cones don’t respond.
Define Cones
Retinal receptor cells that are concentrated near the center of the retina. Function in daylight or well-lit conditions. Detect fine detail and give rise to color sensations.
Define Optic Nerve
The nerve that carries neural impulses from the eye to the brain.
Define Blind Spot
The point at which the optic nerve leaves the eye. Creating a blind spot because no receptor cells are located there.
Define Fovea
The central focal point in the retina.
Define Feature Detectors
Nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, ore movement. Receive information from individual ganglion cells in the retina.
Define Parallel Processing
The processing of many aspects of a problem simultaneously. The brain’s natural mode of information processing for many functions, including vision.
Define Young-Helmholtz Trichromatic Theory
The theory that the retina contains three different color receptors which, when stimulated in combination, can produce the perception of any color. One most sensitive to red, one most sensitive to green, one most sensitive to blue.
Define Opponent-Process Theory
The theory that opposing retinal processes enable color vision. For example, some cells are stimulated by green and inhibited by red and vice versa.
Define Gestalt
An organized whole. Gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes.
Define Figure-Ground
The organization of the visual field into objects that stand out from their surroundings.
Define Grouping
The perceptual tendency to organize stimuli into coherent groups. Illustrate how the perceived whole differs from the sum of its parts.
Define Depth Perception
The ability to see objects in three dimensions although the images that strike the retina are two-dimensional. Allows us to judge distance.
Define Visual Cliff
A laboratory device for testing depth perception in infants and young animals.
Define Binocular Cues
Depth cues, such as retinal disparity, that depend on the use of two eyes.
Define Retinal Disparity
A binocular cue for perceiving depth. By comparing images from the retinas in the two eyes, the brain computes distance. The greater the difference between the two images, the closer the object.
Define Monocular Cues
Depth cues, such as interposition and linear perspective, available to either eye alone.
Define Phi Phenomenon
An illusion of movement created when two or more adjacent lights blink on and off in quick succession.
Define Perceptual Constancy
Perceiving objects as unchanging even as illumination and retinal images change.
Define Color Constancy
Perceiving familiar objects as having consistent color, even as illumination and retinal images change.
Define Perceptual Adaptation
In vision, the ability to adjust to an artificially displaced or even inverted visual field.
Define Audition
The sense or act of hearing.
Define Frequency
The number of complete wavelengths that pass a point in a given time.
Define Pitch
A tone’s experienced highness or lowness. Depends on frequency: long waves have low frequency and pitch, short waves have high frequency and pitch.
Define Middle Ear
The chamber between the eardrum and cochlea. Contains three tiny bones that concentrate the vibrations of the eardrum on the cochlea’s oval window: the hammer, anvil, and stirrup.
Define Cochlea
A coiled, boney, fluid-filled tube in the inner ear. Sound waves traveling through the cochlear fluid trigger nerve impulses.
Define Inner Ear
The innermost part of the ear. Contains the cochlea, semicircular canals, and vestibular sacs.
Define Sensorineural Hearing Loss
Hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerves, also called nerve deafness. Occasionally caused by disease, but more often caused by biological changes linked with heredity, aging, and prolonged exposure to ear-splitting noise.
Define Conduction Hearing Loss
Hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea.
Define Cochlear Implant
A device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea. They do not enable hearing in adults if their brain never learned to process sound during childhood.
Define Place Theory
In hearing, the theory that links the pitch we hear with the place where the cochlea’s membrane is stimulated.
Problem: Place theory can explain how we hear high-pitched sounds but not low-pitched sounds. Neural signals generated by low-pitched sounds are not so neatly localized on the basilar membrane.
Define Frequency Theory
In hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch.
Problem: doesn’t explain how we can sense sounds with frequencies above 1000 waves per second. An individual neuron cannot fire faster than 1000 times per second.
Define Gate-Control Theory
The theory that the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass on to the brain. The “gate” is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain.
Define Kinesthesia
The system for sensing the position and movement of individual body parts.
Define Vestibular Sense
The sense of body movement and position, including the sense of balance.
Define Sensory Interaction
The principle that one sense may influence another, as when the smell of food influences its taste.
Define Embodied Cognition
In psychological science, the influence of bodily sensations, gestures, and other states on cognitive preferences and judgements.
