In psychology, the signal detection theory predicts how we detect the presence of a faint signal amid background noise. Detection depends on a person's experiences, expectations, and alertness.
Absolute Threshold
The absolute threshold is the minimum stimulation required to detect a particular stimulus 50% of the time.
Top-Down Processing
In top-down processing, we form perceptions starting with larger objects, concepts, or ideas before working our way down to smaller, detailed information.
Bottom-Up Processing
Bottom-up processing is an analysis that begins with the sensory receptors and works its way up to the brain's integration of sensory information and perception.
Perception
Perception involves organizing and interpreting sensory information, which enables us to recognize meaningful objects and events.
- Grouping
In order to organize stimuli into coherent groups, our brains group similar items together even if they are different, based on their proximity to each other.
Figure-Ground
The figure-ground refers to the visually organizing of a field into objects that stand out from their surroundings.
Visual Capture
Visual capture occurs when vision competes with other senses for our attention.
Gestalt
Gestalt refers to the perception of a form or whole, in which we perceive objects as whole entities, rather than as a collection of individual parts.
Vestibular Sense
The vestibular sense is the sense of body movements and position, which also includes the sense of balance, particularly in the head.
Finesthesis
The finesthesis system is responsible for sensing the position and movement of individual body parts.
The gate-control theory states that the spinal cord contains a neurological "gate" that blocks pain signals and allows them to pass through. This gating mechanism is controlled by the activity in larger fibers or by incoming signals from the brain.
Sensorineural Hearing Loss
Sensorineural hearing loss is deafness caused by damage to the cochlea's receptor cells or auditory nerves, also known as nerve deafness.
Selective Attention
Selective attention allows us to focus our awareness on only a limited aspect of all that we experience.
Sensory Interaction
Sensory interaction is the principle that one sense may influence another, such as the smell of food influencing its taste.
Perceptual Set
Perceptual set is a mental predisposition to perceive one thing and not another.
Perceptual Adaptation
Perceptual adaptation is the ability to adapt to an artificially displayed or inverted visual field.
Perceptual Consistency
Perceptual consistency is the ability to perceive an object as unchanging, despite changes in illumination and on the retina.
Phi Phenomenon
The phi phenomenon is an illusion of movement created when two or more adjacent lights blink on and off in quick succession.
Convergence
Convergence is a neuromuscular cue caused by the eyes' inward turn when they view a near object.
Retinal disparity involves comparing two images from the eyeballs to compute distance. The greater the difference between the two objects, the closer it is.
Monocular Cues and Binocular Cues
Monocular cues are visual depth cues available to each eye separately, while binocular cues are depth cues that require input from both eyes.
Visual Cliff
The visual cliff is a lab device used to test depth perception in infants and young animals.
Depth Perception
Depth perception is the ability to see objects in three dimensions and estimate their distance from us.
Wavelength
Wavelength is the distance from the peak of one light or sound wave to the peak of the next, giving rise to our experiences of color and pitch.
Accommodation
Accommodation is the process by which the eye's lens changes shape to focus on near objects.
Retina, Rods, and Cones
The retina is the light-sensitive multilayered inner surface of the eye. Rods are retinal receptors that detect black and white, while cones are retinal receptors that detect fine detail and color sensations.
Feature Detectors and Parallel Processing
Feature detectors are nerve cells in the brain that respond to specific features of a stimulus, such as angle, shape, or movement. Parallel processing is the brain's natural mode of information processing for many functions, including vision.
Place Theory and Frequency Theory
Place theory links the pitch we hear with the place where the cochlea's membrane is stimulated. Frequency theory involves the rate of nerve impulses traveling up the auditory nerve matching the frequency of a tone, allowing us to sense pitch.
Conductive Hearing Loss
Conductive hearing loss refers to damage to the mechanical system that conducts sound waves to the cochlea.
