Chapter 5- Sensation Flashcards
Perception
The process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events.
Similar to top down processing.
Sensation
The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.
Similar to bottom up processing
Bottom-up processing
Analysis that begins with the sensory receptors and works up the brains integration of sensory information.
Similar to sensation
Top-down processing
Information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experiences and expectations.
Similar to perception
Prosopagnosia
Complete sensation, incomplete process. They take the senses in but can’t process it. They don’t “top-down”. They have no facial recognition.
Psychophysics
The study of relationships between the physical characteristics of stimuli, such as intensity, and our psychological experience of them.
Absolute threshold
The minimum 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). Assumes there is no absolute threshold and the detection depends partly on experience, expectations, motivation, and level of fatigue.
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 for detection 50% of the time. We experience the 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
Diminishing sensitivity as a consequence of constant motion
Transduction
Encoding physical energy as neural signals. Transforming of stimulus energies, such as sights, sounds, and smell.
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.
Hue
The dimension of color that is determined by the wavelength of light; what we know as the color names of 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 tissues that firms 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 on the retina.
Accommodation
The process by which the eyes lens change shape 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 information.
Acuity
The sharpness of vision
Nearsightedness
A condition in which nearby objects are seen more clearly than distant objects because distant objects focus in front of the retina.
Farsightedness
A condition in which faraway objects are seen more clearly than nearby objects because the image of near objects is focused behind the retina.
Rods
Retinal receptors that detect black, white, and gray; necessary for peripheral twilight vision, when cones don’t respond.
Cones
Retinal receptors that are concentrated near the center of the retina and that function in daylight or in well lit conditions. The cones detect fine detail and give rise to color sensation.
Bipolar cells
Rod and cone cells act to transmit signals from the photoreceptors to the ganglion cells.
Ganglion cells
Neuron near the inner surface of the retina of the eye. Receives visual information from photoreceptors. They transmit images forming and non image forming visual information from the retina to the thalamus, hypothalamus, etc.
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 shape, angle, or movement.
Parallel processing
The processing of several aspects of a problem simultaneously; the brains natural mode of information processing for many functions, including vision. Contrasts with a step by step process.
Blindsight
The ability of people who are cortically blind due to lesions in their striate cortex to respond to visual stimuli that they do not consciously see.
Young-Helmoltz trichromatic theory
The manner in which the photoreceptor cells in the eyes of humans and other primates work to enable color vision.
Opponet- process theory
Color perception is controlled by the activity of two opponent systems; a blue-yellow mechanism and a red-green mechanism.
Color constancy
Perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object.
Audition
The sense or act of hearing.
Frequency
The number of complete wavelengths that pass a point in a given time, per second.
Pitch
A tones experienced highness or lowness; depends on frequency.
Middle ear
The chamber between the eardrum and cochlea, containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochleas oval window.
Cochlea
A coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses.
Cilia
Short, hairlike, rhythmically beating organelles on the surface of certain cells at provide mobility. The eyelashes.
Inner ear
The inter most part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.
Place theory
In hearing, the theory that links the pitch we hear with the place that cochleas membrane is stimulated.
Frequency theory
In hearing, the theory that the rate of nerves and impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense it’s pitch
Conduction hearing loss
Hearing loss caused by damage to the mechanical system that conductus sound waves to the cochlea.
Sensorineural hearing loss
Hearing loss caused by damage to the cochleas receptor cells or to the auditory nerves, aka nerve deafness.
Cochlear implant
A deceive 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 launched signals or allows them to pass onto the brain. The “gate “ opens for pain and is closed by fibers in the brain.
Sensory interaction
The principle that one sense may influence another such as when the smell of food influences our taste.
McGurk Effect
An interaction between hearing and vision in speech perception. The visual information changes from the sound (like when a movie is dubbed and the mouths don’t match the sound you hear.)
Olfaction
The sense of smell. When odorant molecules bind to specific sites in the olfactory receptors.
Synesthesia
Stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway.
Kinesthesis
The system for sensing the position and movement of individual body parts.
Vestibular sense
The sense of body movement and position, including the sense of balance.
