Psychology: Sensation, Perception, and Learning

A comprehensive vocabulary review of core concepts in sensation, perception, and learning, covering sensory systems, psychophysics, classical conditioning, operant conditioning, and observational learning.

Psychophysics

The study of how physical stimuli are translated into psychological experience.

Transduction

The sensory process through which sensory receptors convert physical stimuli into neural signals that are processed and interpreted by the brain.

Absolute Threshold

The smallest amount of physical stimulation required to detect a sensory input half of the time it is present.

Weber's Law

The principle that the size of a just noticeable difference is a constant proportion of the size of the initial stimulus, represented by the equation $\frac{\Delta I}{I} = k$.

Feature Detectors

Neurons in the visual cortex discovered by David Hubel and Torsten Wiesel that respond selectively to specific features of complex stimuli, such as lines and edges.

Ventral Stream

The "What" visual processing pathway originating in the primary visual cortex that is specialized for the perception of form and color.

Dorsal Stream

The "Where" visual processing pathway originating in the primary visual cortex that is specialized for the perception of motion and spatial depth.

Prosopagnosia

A specific type of visual agnosia characterized by the inability to recognize faces, associated with the fusiform face area.

Visual Cliff

An experimental apparatus developed by Eleanor Gibson featuring an elevated glass floor and a simulated drop-off, designed to evaluate the development of depth perception across species and human infants.

Phi Phenomenon

An illusion of movement created by presenting visual stimuli in rapid succession.

Retinal Disparity

A binocular depth cue arising because each eye observes a slightly different view of an object due to the physical separation between the eyes.

Place Theory

A theory of hearing stating that hair cells at different locations along the basilar membrane respond independently to different sound frequencies.

Presbycusis

Hearing loss caused by old age, commonly affecting the detection of higher frequency sound waves.

Auditory Localization

The perception of a sound source's spatial location based on loudness intensity differences and timing differences between the ears that can be as small as $1/100{,}000$ of a second.

Papillae

Small structures located on the tongue that contain groupings of taste buds.

Gate Control Theory

A theory formulated by Patrick Wall and Ronald Melzack proposing that a neural gate in the spinal cord opens or closes to regulate how much pain stimulation travels to the brain.

Kinesthetic Sense

An internal sensory system that provides feedback from muscles, tendons, and joints to guide and coordinate voluntary bodily movement.

Fast Fibers

Myelinated nerve axons that transmit sharp, immediate pain sensations to safeguard the body from intense pressure and extreme temperatures.

Habituation

A form of non-associative learning in which a behavioral response to a stimulus decreases after lengthy or repeated exposure, particularly when the stimulus is neither harmful nor rewarding.

Sensitization

A form of non-associative learning in which a behavioral response to a stimulus increases after lengthy or repeated exposure, heightening preparedness in situations with potential harm or reward.

Conditioned Stimulus (CS)

An initially neutral stimulus that does not naturally produce a reflexive reaction, but comes to trigger a conditioned response after being paired with an unconditioned stimulus.

Spontaneous Recovery

The reappearance of an extinguished conditioned response after a period of rest or no exposure to the conditioned stimulus.

Law of Effect

Edward Thorndike's principle that behaviors followed by favorable consequences become more likely to be repeated, whereas behaviors followed by unfavorable consequences become less likely.

Skinner Box (Operant Chamber)

A laboratory apparatus developed by B. F. Skinner equipped with mechanisms such as levers, lights, and food dispensers to study operant conditioning and reinforcement schedules.

Vicarious Conditioning

A form of observational learning where individuals learn to perform or avoid a behavior after observing others experience reinforcement or punishment for that action.