Chapter 5: Sensation Flashcards
Sensation
(in the moment processing) the process by which our senses, sensory receptors and nervous system, receive stimuli and sends it to the brain. -
Perception
the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events. -
Bottom-up Processing
analysis that begins with the sensory receptors and works up to the brain’s integration of sensory information. -
Top-down Processing
information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations. -
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 stimulation needed to detect a particular stimulus 50 percent 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 single absolute threshold and detection depends partly on a person’s experience, expectations, motivation, and level of fatigue. -
Subliminal
below one’s absolute threshold for conscious awareness. -
Difference Threshold
the minimum difference between two stimuli required for detection 50 percent of the time. -
Weber’s Law
states that the difference threshold is directly proportional to the magnitude of the stimulus with which the comparison is being made. -
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. -
Hue
the dimension of color that is determined by the wavelength of light. -
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. -
Pupil
the adjustable opening in the center of the eye through which light enters. -
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. -
Lens
the transparent structure behind the pupil that changes shape to help focus images on the retina. -
Accomodation
the process by which the eye’s lens changes shape to focus near or far objects on the retina. -
Rods
retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don’t respond. -
Cones
retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. Detect fine detail and give rise to color sensations. -
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, no receptor cells are located there. -
Fovea
the central focal point in the retina, around which the eye’s cones cluster. -
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 near objects because the image of near objects is focused behind the retina. -
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 brain’s natural mode of information processing for many functions, including vision. -
Young-Helmholtz Theory
the theory that the retina contains three different color receptors - one most sensitive to red, one to green, one to blue - which when stimulated in combination can produce the perception of any color. -
Opponent-Process Theory
the theory that opposing retinal processes enable color vision. -
Color Constancy
perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object. -
Audition
the sense of hearing. -
Frequency
the number of waves that pass a given point in a specific time, usually one second. -
Pitch
a tone’s experienced highness or lowness; depends on frequency. -
Middle Ear
the chamber between the eardrum and cochlea containing three tiny bones that concentrate the vibrations of the eardrum on the cochlea’s oval window. -
Inner Ear
the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs. -
Cochlea
a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses. -
Place Theory
in hearing, the theory that links the pitch we hear with the place where the cochlea’s 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, thus enabling us to sense its pitch. -
Conduction Hearing Loss
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea. -
Nerve Deafness
hearing loss created by damage to the hair cells or the auditory nerve fibers in the inner ear. -
Gate Control Theory
theory that spinal cord contains neurological gate that blocks pains signals or allows them to pass. Opened by activity of pain going up small nerve fibers & is closed by act of large fibers or by info coming from brain. -
Sensory Interaction
the principle that one sense may influence another, as when the smell of food influences its taste. -
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. -
Sensorineural Hearing Loss
hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerves; also called nerve deafness. -
