the process by which we detect physical energy from the environment and encode it as neural signals.
the process by which the brain selects, organizes, and interprets sensory information.
the study of relationships between the physical characteristics of stimuli and our psychological experience of them.
analysis that begins with the sense receptors and works up to the brain's integration of sensory information.
information processing guided by higher-level mental processes.
the minimum stimulation needed to detect a stimulus 50 percent of the time.
a theory predicting how and when we detect the presenceof a faint stimulus (signal) amid background stimulation (noise). Assumes there is no single absolute threshold and that detection depends partly on a person's experience, expectations, motivation, and level of fatigue.
A stimulus that is is below the absolute threshold for awareness. Memory aid: Limen is the Latin word for "threshold." A stimulus that is sub- (below) the limen, or threshold.
the minimum difference in two stimuli that a subject can detect 50 percent of the time, or just noticeable difference (jnd).
the just noticeable difference between two stimuli is a constant minimum proportion of the stimulus. Example: If a difference of 10 percent in weight is noticeable, Weber's law predicts that a person could discriminate 10- and 11-pound weights or 50- and 55-pound weights.
the decreased sensitivity that occurs with continued exposure to an unchanging stimulus.
The process by which a form of physical energy is converted into a coded neural signal that can be processed by the nervous system
the distance from the peak of one light or sound wave to the next, gives rise to the perceptual experiences of hue, or color, in vision (and pitch in sound).
The degree of light and sound that determined the amplitude of the waves and is experienced as brightness and loudness, respectively. Example: Sounds that exceed 85 decibels in amplitude will damage the auditory system.
A clear membrane covering the visible part of the eye that helps gather and direct incoming light
the opening in the middle of the iris that changes size to let in different amounts of light.
the colored part of the eye, which is the muscle that controls the size of the pupil
a transparent structure located behind the pupil that actively focuses, or bends, light as it enters the eye
the process by which the lens of the eye changes shape to focus near objects on the retina
the light-sensitive, multi-layered inner surface of the eye that contains the rods and cones, as well as neurons that form the beginning of the optic nerve.
a condition in which nearby objects are seen more clearly than distant objects because distant objects focus in front of the retina.
a condition in which far-away objects are seen more clearly than near objects because distant objects is focused behind the retina.
A visual receptor that transform light into neural impulses. These have poor sensitivity, detect black and white, and function well in dim light.
A visual receptor that transform light into neural impulses. These have excellent sensitivity, enable color vision, and function best in daylight or bright light.
in the retina, the specialized neurons that connect the rods and cones with the ganglion cells
In the retina, the specialized neurons that connect to the bipolar cells; the bundled axons of the ganglion cells form the opic nerve
Comprised of the axons of retinal ganglion cells, this carries neural impulses from the eye to the brain.
the region of the retina where the optic nerve leaves the eye. Because there are no rods or cones in this area, there is no vision here.
a small area in the center of the retina, composed entirely of cones, where visual information is most sharply focused.
located in the visual cortex of the brain, are nerve cells that selectively respond to specific visual features, such as movement, shape, or angle. Feature detectors are evidently the basis of visual information processing.
information processing in which several aspects of a stimulus, such as light or sound, are processed simultaneously.
The property of wavelengths of light known as color; different wavelengths correspond to our subjective experience of different colors.
the property of color that corresponds to the purity of the light wave
the perceive intensity of a color, which corresponds to the amplitude of the light wave.
The theory maintains that the retina contains red-, green-, and blue-sensitive color receptors that in combination can produce the perception of any color. This theory explains the first stage of color processing.
one of several inherited forms of color deficiency or weakness in which an individual cannot distinguich between certain colors.
A visual experience that occurs after the original source of stimulation is no longer present
The theory maintains that color vision depends on pairs of opposing retinal processes (red-green, yellow-blue, and white-black). This theory explains the second stage of color processing.
the perception that familiar objects have consistent color despite changes in illumination that shift the wavelengths they reflect.
the technical term for the sense of hearing.
the intensity (or amplitude) of a sound wave, measured by decibels.
the intensity or amount of energy of a wave, reflected in the height of the wave; the amplitude of a sound wave determines a sound's loudness
The relative highness or lowness of a sound, determined by the frequency of a sound wave
directly related to wavelength: Longer waves produce lower pitch; shorter waves produce higher pitch.
The distinctive quality of a sound, determined by the complexity of the sound wave.
The unit of measurement for loudness
The part of the ear that amplifies sound waves; consists of three small bones: the hammer, the anvil, and the stirrup
a tightly stretched membrane at the end of the ear canal that vibrates when hit by sound waves
the part of the ear where sound is transduced into neural impulses; consists of the cochlea and semicurcular canal
the coiled, bony, fluid-filled tube of the inner ear where the transformation of sound waves into neural impulses occurs.
the membrane within the cochlea of the ear that contains the hair cells
Relays information about intensity, frequency and timing
in hearing, the theory that links the pitch we hear with the place where the cochlea's membrane is stimulated
in hearing, the theory that the rate of nerve inpulses 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
Sensorineural hearing loss
hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness
a device for converting sounds into electircal signals and stimulating the auditory nerve through electrodes threaded into the cochlea
Melzack and Wall's maintains that a "gate" in the spinal cord determines whether pain signals are permitted to reach the brain. Neural activity in small nerve fibers opens the gates; activity in large fibers or information from the brain closes the gate.
technical name for the sense of smell
technical name for the sense of taste
the principle that one sense may influence another, as when smell of food influences its taste
The sense of body movement and position, including the sense of balance
The technical name for the the sense of the location and position of body parts in relation to one another