Ch. 5 Flashcards
Perception
The process of organizing and intepreting
sensory information, enabling us to recognize meaningful objects and events.
Sensation
The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.
Bottom up processing
Analysis that begins with the sensory receptors and works up to the brains integration of sensory info.
Top down processing
Information processing guided by higher level mental processes, as when we construct perceptions drawing on our experiences and expectations.
Prosopagnosia
Complete sensation but incomplete perception.
Psychophysics
The study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them.
Absolute threshold
The minimum amount of stimulation needed to detect a particular stimulus 50% of the time.
Signal detection theory
A theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise)
Subliminal
Below ones absolute threshold for conscious awareness.
Priming
The activation, often unconsciously, of certain associations, thus predisposing ones perception, memory, or response.
Difference threshold
The minimum difference between two stimuli required for detection 50% of the time. We experience difference threshold as a just noticeable difference.
Webers law
The principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount).
Sensory adaptation
Diminished sensitivity as a consequence of constant stimulation.
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 brains can interpret.
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 days to the long pulses of radio transmission.
Hue
The dimension of color that is determined by the wavelength of light; what we know as the color names, blue, green, etc.
Intensity
The amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the waves amplitude.
Pupil
The adjustable opening in the center of the eye through which light enters.
Iris
A ring of muscle tissue that or a the colored portion of the eye around the pupil and controls the size of the pupil opening.
Lens
The transparent structure behind the pupil that changes shape to help focus images in the retina.
Accommodation
The process by which the eyes lens changes share to focus near or far objects on the retina.
Retina
The light-sensitive inner surface of the eye, containing the receptor rods and cones, plus layers of neurons that begin the processing of visual info.
Acuity
The sharpness of vision
Nearsightedness
A condition in which nearby objects are seen more clearly than distant objects be aide distant objects focus in the front of the retina.
Farsightedness
A condition in which far away objects are seen more clearly than near objects because the image of near objects is focused behind the retina.
Rods
Retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision; when cones don’t respond.
Cones
Retinal receptors that are concentrated near the center of retina, function in daylight or in well lot conditions. The cones detect fine detail and give rise to color sensation.
Optic nerve
The nerve that carries neural impulses from the eye to the brain.
Blind spot
The point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there.
Fovea
The central focal point in the retina, around which the eyes cones cluster.
Feature detectors
Nerve cells in the brain that respond to specific features of the stimulus, such as shapes angle, or movement.
Parallel processing
Processing of several aspects of a problem simultaneously; the brains natural mode of info processing for many functions, including visions. Contrasts with step by step processing of most computers and if conscious problem solving.
Young-helmholtz trichromatic theory (three color)
Theory that the retina contains 3 different color receptors – one most sensitive to red, one to green, and one to blue. – which when stimulated in combination can produce the perception of any color.
Opponent-process theory
The theory that the opposing retinal processes (red-green, yellow-blue, and white- black) enable color vision.
Ex. Some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green.
Color constancy
Perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object.
Blindsight
Blindness in part of the field of vision due to destruction in the visual cortex from stroke or surgery.
Audition
The sense or act of hearing
Frequency
The number of complete wavelengths that pass a point in a given time (for example, per second)
Pitch
A tones experienced highness or lowness; depends on frequency.
Middle ear
The chamber between the ear drum and cochlea containing three tiny bones (hammer, anvil, stirrup) that concentrate the vibrations of the eardrum on the cochleas oval window.
Cochlea
Coiled, boney, fluid filled tube in the inner ear through which sound waves trigger nerve impulses.
Inner ear
The innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.
Semicircular canals
It’s what makes you feel dizzy when you get off an amusement park ride.
Place theory
In hearing, the theory that links the pitch we hear with the place where the cochleas membrane is stimulated.
Frequency theory
In hearing, the theory that the rate of nerve impulses, traveling up the auditory nerve matches the frequency of a tone, this enabling us to sense it’s pitch.
Conduction hearing loss
Hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea.
Sensorineural hearing loss
Hearing loss caused by damage to the cochleas receptor cells or to the auditory nerves; also called nerve deafness.
Cochlear implant
A device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea.
Gate-control theory
The theory that the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass to the brain. The “gate” is opened by the activity of pain signals traveling up in larger fibers or by info coming from the brain.
Sensory interaction
The principle that one sense may influence another, as when the smell of food influences it’s taste.
Kinesthesis
The system for sensing the position and movement of individual body parts.
