Chapter 4: Sensation and Perception Vocabulary

Vocabulary practice flashcards covering core sensory and perceptual terms from Chapter 4 of Psychology (6th Edition).

Sensation

Simple stimulation of a sense organ, representing the basic registration of light, sound, pressure, odor, or taste as parts of the body interact with the physical world.

Perception

The organization, identification, and interpretation of a sensation in order to form a mental representation.

Transduction

The process that occurs when many sensors in the body convert physical signals from the environment into encoded neural signals sent to the central nervous system.

Sensory Adaptation

The process whereby sensitivity to prolonged stimulation tends to decline over time as an organism adapts to current, unchanging conditions.

Psychophysics

Methods that systematically relate the physical characteristics of a stimulus to an observer's perception.

Absolute Threshold

The minimal intensity needed to just barely detect a stimulus, measured as successful identification on $50\%$ of trials.

Just Noticeable Difference (JND)

The minimal change in a stimulus that can just barely be detected by an observer.

Weber's Law

The principle stating that the just noticeable difference (JND) of a stimulus is a constant proportion despite variations in intensity.

Signal Detection Theory (SDT)

A theory holding that the response to a stimulus depends on a person's sensitivity to the stimulus in the presence of noise and on a person's internal decision criterion.

Visual Acuity

The ability to see fine detail, traditionally measured using a Snellen chart where $20/20$ vision indicates the standard line readable from $20\,\text{feet}$.

Accommodation

The process by which the eye maintains a clear image on the retina by using muscles to change the shape of the lens.

Retina

The light-sensitive tissue lining the back of the eyeball.

Cones

Photoreceptor cells in the retina that detect color, operate under normal daylight conditions, and allow us to focus on fine detail.

Fovea

An area of the retina where vision is the clearest and where there are no rods, only cones.

Rods

Photoreceptor cells in the retina that become active under low-light conditions for night vision.

Blindspot

A location in the visual field that produces no sensation on the retina because the corresponding area contains neither rods nor cones.

Area V1

The region in the occipital lobe containing the primary visual cortex that processes feature orientation and edges.

Ventral Stream

The visual pathway ('what' pathway) running from the occipital visual regions into the lower temporal lobe, enabling recognition of shape and identity.

Dorsal Stream

The visual pathway ('where' pathway) projecting from the occipital cortex to the parietal lobe that processes location and movement.

Binding Problem

The question of how features are linked together by the brain so that we see unified objects in our visual world rather than free-floating features.

Parallel Processing

The brain's capacity to perform multiple perceptual activities at the same time.

Illusory Conjunction

A perceptual mistake whereby features from multiple objects are incorrectly combined.

Feature-Integration Theory

The proposition that focused attention is not required to detect individual features of a stimulus, but is required to bind those features together.

Perceptual Constancy

A perceptual principle stating that even as aspects of sensory signals change, perception remains consistent.

Perceptual Organization

The process of grouping and segregating features to create whole objects organized in meaningful ways.

Rubin's Vase

A classic reversible figure-ground illusion demonstrating the visual separation of an object from its background.

Monocular Depth Cues

Aspects of a scene that yield information about depth when viewed with only one eye.

Binocular Disparity

The difference in the retinal images of the two eyes that provides information about depth.

Ames Room

A specially constructed trapezoidal room that creates a distorted perceptual illusion of depth and size.

Apparent Motion

The perception of movement resulting from alternating signals appearing in rapid succession in different locations.

Synesthesia

A perceptual phenomenon where one attribute of a stimulus leads to the conscious experience of an additional attribute in a different sensory modality.

Pitch

How high or low a sound is perceived, corresponding to the frequency of sound waves.

Loudness

A sound's perceived intensity, corresponding to the amplitude of sound waves.

Timbre

A listener's experience of sound quality or resonance, determined by the complexity and mix of frequencies in a sound wave.

Cochlea

A fluid-filled tube in the inner ear that serves as the organ of auditory transduction.

Basilar Membrane

A structure in the inner ear that undulates when vibrations from the ossicles reach the cochlear fluid.

Area A1

The primary auditory cortex located in the temporal lobe.

Place Code

The pitch perception mechanism used mainly for high frequencies, where the cochlea encodes different frequencies at different locations along the basilar membrane.

Temporal Code

The pitch perception mechanism used for low frequencies, where the cochlea registers pitch via the firing rate of action potentials entering the auditory nerve.

Conductive Hearing Loss

Hearing impairment resulting from physical damage to the eardrum or ossicles.

Sensorineural Hearing Loss

Hearing impairment caused by damage to the cochlea, hair cells, or auditory nerve.

Haptic Perception

The active exploration of the environment through touching and grasping objects with our hands.

Referred Pain

The feeling of pain when sensory information from internal organs and external body regions converges on the same nerve cells in the spinal cord.

Gate-Control Theory

The theory stating that signals arriving from pain receptors can be stopped or gated by interneurons in the spinal cord via feedback from the periaqueductal gray (PAG).

Vestibular System

The three fluid-filled semicircular canals and adjacent organs in each inner ear used with visual feedback to maintain balance.

Olfactory Receptor Neurons (ORNs)

Receptor cells in the olfactory epithelium that initiate the sense of smell.

Olfactory Bulb

A brain structure located above the nasal cavity beneath the frontal lobes where ORN axons converge on glomeruli.

Pheromones

Biochemical odorants emitted by other members of a species that can affect an animal's behavior or physiology.

Taste Buds

The organs of taste transduction housed within papillae on the tongue.