AP Psych Study Guide: Sensation and Perception

Transduction

Converting sensory information into signals the brain can understand.

● Sensation

The process of sensing our environment through touch, taste, sight, sound, and smell.

● Perception

How our brain organizes and interprets sensory information.

● Selective Attention

Focusing on one specific thing while ignoring others.

● Bottom-Up Processing

Understanding something by starting with details and building up to a whole.

● Top-Down Processing

Using prior knowledge to interpret and make sense of information.

● Psychophysics

The study of how physical stimuli relate to sensations and perceptions.

● Thresholds

The minimum level of stimulus intensity needed for detection.

● Gustav Fechner

A psychologist who helped develop psychophysics.

● Absolute Threshold

The smallest amount of a stimulus that can be detected.

● Subliminal Threshold

Stimuli below the absolute threshold that can still affect behavior.

● Priming

Exposure to a stimulus influences a response to a later stimulus.

● Difference Threshold

The smallest difference in stimulation that can be detected between two stimuli.

● Weber’s Law

States that the difference threshold is a constant proportion of the original stimulus.

● Sensory Adaptation

Decreased sensitivity to a constant stimulus over time.

● Gestalt and His Laws

A psychologist who proposed principles of how we organize visual information, such as grouping.

● Schema

A mental framework that helps organize and interpret information.

● Accommodation

Adjusting schemas to incorporate new information.

● Assimilation

Interpreting new information based on existing schemas.

● Figure-Ground

Distinguishing an object (figure) from its background (ground).

● Visual Cliff

A test to determine if depth perception is innate.

● Depth Perception

The ability to judge distance and see objects in three dimensions.

● Monocular Cues

Depth cues that only require one eye.

● Binocular Cues

Depth cues that require both eyes.

● Convergence

The inward movement of the eyes when focusing on close objects.

● Linear Perspective

Parallel lines appear to converge with distance.

● Interposition

When one object overlaps another, indicating depth.

● Perceptual Constancy

Recognizing objects as unchanging despite changes in viewpoint or lighting.

● Perceptual Adaptation

The ability to adjust to changed sensory input, like a visual shift.

● Perceptual Set

A tendency to perceive things a certain way based on expectations.

● Stroboscopic Movement

A motion illusion created by rapidly showing a sequence of still images.

● Phi Phenomenon

The illusion of movement created by flashing lights in sequence.

● Autokinetic Effect

An illusion where a stationary point of light appears to move in a dark room.

● Wavelength and Its Influence on Color

Wavelength determines the color we see, with longer wavelengths appearing red and shorter wavelengths appearing blue.

● Intensity and Its Influence on Color

The brightness of color, determined by the light wave’s amplitude.

● Cornea

The clear, outer layer of the eye that helps focus incoming light.

● Iris

The colored part of the eye that controls the size of the pupil.

● Retina

The light-sensitive layer at the back of the eye containing photoreceptors.

● Optic Nerve

Transmits visual information from the retina to the brain.

● Fovea

The central part of the retina with the highest concentration of cones, for sharp vision.

● Rods

Photoreceptors in the retina that detect light and are sensitive in low-light conditions.

● Cones

Photoreceptors in the retina that detect color and function best in bright light.

● Hue

The color we perceive, which depends on wavelength.

● Trichromatic Theory of Color

Theory stating color vision is based on three types of cones sensitive to red, green, and blue.

● Opponent Processing Theory of Color

Theory that color vision is controlled by opposing pairs of colors (e.g., red-green).

● Hammer, Anvil, Stirrup

Small bones in the middle ear that transmit sound vibrations to the inner ear.

● Frequency and Its Influence on Sound

Frequency determines the pitch of sound, with higher frequencies producing higher pitches.

● Pitch and Its Influence on Sound

The highness or lowness of a sound, related to frequency.

● Cochlea

A spiral-shaped organ in the inner ear that converts sound vibrations into neural signals.

● Semicircular Canal

Part of the inner ear that helps with balance by sensing head rotation.

● Basilar Membrane

A structure in the cochlea that vibrates and aids in sound detection.

● Sensorineural Hearing Loss

Hearing loss due to damage to the inner ear or auditory nerve.

● Conduction Hearing Loss

Hearing loss caused by damage to the middle or outer ear that affects sound transmission.

● Kinesthesis

The sense of body position and movement of muscles and joints.

● Vestibular Sense

The sense of balance and spatial orientation.

● Nociceptors

Sensory receptors that detect pain.

● Gate Control Theory

Theory that the spinal cord has a “gate” that can block or allow pain signals to reach the brain.

● Influences of Pain

Psychological factors like attention, mood, and experience can affect pain perception.

● Taste Receptors

Cells on the tongue that detect sweet, sour, salty, bitter, and umami flavors.

● Sensory Interaction

How different senses influence each other, like taste being affected by smell.

● Olfaction

The sense of smell.

● Gustation

The sense of taste.

● Steps to Process Light

Light enters the eye, is focused by the lens, hits the retina, and is converted into neural signals sent to the brain.

● Steps to Process Sound

Sound waves enter the ear, are amplified by ear bones, and are converted to neural signals in the cochlea.

● Steps to Process Smell

Odor molecules bind to receptors in the nose, sending signals to the brain.

● Feature Detectors

Neurons that respond to specific visual aspects like shapes, angles, and movement.

● Blind Spot

The point where the optic nerve leaves the eye, with no photoreceptors.

● Synesthesia

A condition where stimulation of one sense involuntarily triggers another, like seeing colors when hearing music.

● Selective Attention

The process of focusing on one specific aspect of experience.

● Change Blindness

Failing to notice changes in a visual scene.

● Inattentional Blindness

Failing to see visible objects when attention is focused elsewhere.