Biological Bases of Behavior: Sensation and Perception

Vocabulary practice flashcards covering sensation fundamentals, visual and auditory anatomy, perceptual theories, and sensory interactions from AP Psychology.

Sensation

The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.

Perception

The process of organizing and interpreting sensory information to make sense of the world around us, influenced by past experiences, expectations, and context.

Transduction

The conversion of sensory stimuli into neural impulses that can be understood by the brain; the transformation of physical energy into electrochemical signals.

Absolute Threshold

The minimum amount of stimulation required for a stimulus to be detected by a sensory system at least $50\%$ of the time.

Just-Noticeable Difference (JND)

The smallest change in a stimulus that can be detected by an individual; the minimal difference needed to perceive that a change has occurred.

Weber's Law

The principle stating that the perceived difference in a stimulus must be proportional to the original intensity of the stimulus; the larger the stimulus, the greater the change required to notice a difference.

Sensory Adaptation

The process by which sensory receptors become less responsive to constant, unchanging stimuli over time.

Synesthesia

A condition in which stimulation of one sensory pathway leads to automatic, involuntary experiences in another sensory pathway.

Retina

The light-sensitive inner surface of the eye containing photoreceptor cells (rods and cones) that convert light into neural signals.

Rods

Photoreceptor cells in the retina responsible for black-and-white vision in low light conditions and for detecting motion.

Cones

Photoreceptor cells in the retina responsible for color vision and fine visual details in bright light.

Fovea

The central area of the retina containing a high concentration of cone cells and no rods, responsible for sharp central vision and high visual acuity.

Blind Spot

The area on the retina where the optic nerve exits the eye, lacking photoreceptor cells and resulting in an absence of visual detection.

Ganglion Cells

Neurons in the retina that receive visual information from bipolar cells and transmit it to the brain via the optic nerve.

Lens

The transparent structure in the eye that focuses light onto the retina by adjusting its shape and curvature.

Accommodation

The process by which the lens of the eye alters its curvature to focus on objects at varying distances.

Nearsightedness (Myopia)

A visual condition where close objects appear clear but distant objects appear blurry, occurring when the eyeball is too long or the cornea is too curved, focusing light in front of the retina.

Farsightedness

A visual condition where distant objects are seen more clearly than close ones, occurring when the eyeball is too short or the cornea is too flat, focusing light behind the retina.

Trichromatic Theory

The theory proposing that color vision is based on three types of cone receptors in the retina, each sensitive to specific wavelengths corresponding to red, green, and blue.

Opponent-Process Theory

The theory proposing that color vision depends on opposing retinal processes for three pairs of colors: red-green, blue-yellow, and black-white.

Afterimages

Visual sensations that persist after a stimulus has been removed, caused by temporary overstimulation and adaptation of cone cells in the retina.

Dichromatism

A type of color vision deficiency where an individual possesses only two types of functioning cone cells instead of the normal three, leading to difficulty distinguishing certain colors such as reds and greens.

Monochromatism

A rare form of color blindness in which an individual has only one functioning cone type or none at all, causing vision to consist entirely of shades of gray.

Blindsight

A condition in which individuals with damage to the primary visual cortex can respond accurately to visual stimuli without consciously perceiving them.

Prosopagnosia

A neurological condition characterized by the inability to recognize familiar faces, including one's own face, despite intact visual acuity and intellect; also known as face blindness.

Cochlea

The coiled, bony structure in the inner ear where auditory transduction occurs, housing hair cells in the Organ of Corti that convert vibrations into neural signals.

Wavelength (Sound)

The distance between sound wave peaks; shorter wavelengths correspond to higher-pitched sounds, whereas longer wavelengths correspond to lower-pitched sounds.

Amplitude (Sound)

The height of sound wave peaks, which measures sound intensity or loudness; greater amplitude corresponds to louder sounds.

Pitch Perception

The auditory system's interpretation of sound wave frequency, determining whether a tone is perceived as high or low.

Place Theory

A pitch perception theory stating that different frequencies stimulate hair cells at specific regions of the basilar membrane, with high frequencies detected at the basal end and low frequencies near the apical end.

Frequency Theory

A pitch perception theory proposing that the frequency of a sound wave directly matches the firing rate of auditory nerve fibers.

Volley Theory

A theory of pitch perception proposing that auditory neurons fire in rapid succession or volleys to encode frequencies exceeding $1000\text{ Hz}$, overcoming individual neural firing rate limits.

Sound Localization

The brain's process of determining the spatial origin of a sound using differences in arrival time, intensity between ears, and spectral cues.

Conduction Deafness

Hearing impairment resulting from mechanical damage or physical blockage in the outer or middle ear, such as issues with the ear canal, eardrum, or ossicles.

Sensorineural Deafness

Hearing loss caused by damage to the cochlea's hair cells or the auditory nerve, commonly irreversible and linked to aging, disease, or loud noise exposure.

The McGurk Effect

A perceptual illusion demonstrating the interaction between hearing and vision, in which auditory input for one sound is combined with visual input of another sound to produce the perception of a third distinct sound.

Sensory Interaction

The principle that one sensory modality can influence and interact with another sensory modality, such as smell influencing the perception of taste.

Olfactory System

The sensory system responsible for the sense of smell, utilizing olfactory receptor cells in the nasal cavity that detect odorants and convey signals to the brain.

Pheromones

Chemical signals secreted by organisms that elicit physiological, social, or behavioral reactions in other members of the same species.

Gustation

The sense of taste, involving specialized taste receptor cells on the tongue and oral cavity detecting sweet, sour, salty, bitter, umami, and oleogustus flavors.

Gate Control Theory

The theory that the spinal cord contains a neurological 'gate' that either blocks pain signals or allows them to pass on to the brain, modulated by competing tactile inputs.

Phantom Limb

The persistent perception of sensation or pain in an amputated limb, resulting from cortical reorganization and neural plasticity in the somatosensory cortex.

Vestibular Sense

The sensory system that monitors head position, movement, balance, and spatial orientation via inner ear structures.

Semicircular Canals

Three fluid-filled loops in the inner ear lined with hair cells that detect rotational acceleration and head movement.

Kinesthesis

The sensory system providing information about the position and movement of individual body parts through receptors located in muscles, tendons, and joints.