psych unit 4

Sensation

Process of receiving stimulus from the environment

Perception

Process of organizing and interpreting sensory information

Bottom-up Processing

Analysis that starts with sensory receptors and works up to the brain

Top-down Processing

Information processing guided by higher level mental processes

Selective Attention

Ability to focus on one voice among many

Inattentional Blindness

Failing to see visible objects when attention is directed elsewhere

Change Blindness

Failing to notice changes in the environment

Transduction

Conversion of one form of energy into another for interpretation by the brain

Psychophysics

Study of the relationship between physical stimuli and psychological experiences

Absolute Threshold

Minimum amount of stimulus that can be detected 50% of the time

Signal Detection Theory

Predicts how and when we detect faint stimuli in the presence of background stimulation

Subliminal

Below the absolute threshold for conscious awareness

Priming

Activation of certain associations that influence perception, memory, or response

Difference Threshold

Minimum difference between two stimuli required for detection 50% of the time

Weber's Law

Perception of differences between stimuli depends on a constant minimum percentage difference

Sensory Adaptation

Diminished sensitivity due to constant stimulation

Perceptual Set

Mental predisposition to perceive one thing over another

Extrasensory Perception (ESP)

Claim that perception can occur apart from sensory input

Parapsychology

Study of paranormal phenomena, including ESP and psychokinesis

Wavelength

Distance between the peaks of a light or sound wave

Hue

Dimension of color determined by the wavelength of light

Intensity

Amount of energy in a light or sound wave, perceived as brightness or loudness

Pupil

Adjustable opening in the center of the eye

Iris

Ring of muscle that controls the size of the pupil

Lens

Transparent structure behind the iris that changes shape to focus images on the retina

Retina

Contains visual sensory receptors (rods and cones)

Accommodation

Process by which the eye's lens changes shape to focus on near or far objects

Rods

Visual receptors that help see black and white in the peripheral retina

Cones

Visual receptors that help see color in the central retina

Optic Nerve

Pathway to the brain's visual cortex

Blind Spot

Location in the retina where there are no sensory receptors

Fovea

Point of central focus in the retina, contains most of the eye's cones

Feature Detectors

Nerve cells in the brain that respond to specific features of a stimulus

Parallel Processing

Processing multiple aspects of a stimulus simultaneously

Young-Helmholtz Trichromatic Theory

Theory that there are three types of color receptors in the retina

Opponent-Process Theory

Theory that some color combinations oppose each other

Gestalt

Principles used to organize perception into connected wholes

Figure-Ground

Organization of the visual field into objects that stand out from their surroundings

Grouping

Perceptual tendency to organize stimuli into coherent groups

Depth Perception

Ability to see objects in three dimensions

Binocular Cues

Depth cues that depend on the use of both eyes

Retinal Disparity

Binocular cue for perceiving depth based on differences between the images received by each eye

Monocular Cues

Depth cues available to either eye alone

Phi Phenomenon

Illusion of movement created by blinking lights in quick succession

Perceptual Constancy

Perceiving objects as unchanging despite changes in illumination or retinal images

Color Constancy

Perceiving familiar objects as having consistent color despite changing illumination

Perceptual Adaptation

Ability to adjust to an artificially displaced or inverted visual field

Audition

Sense or act of hearing

Frequency

Number of complete wavelengths that pass through a point in a given time

Pitch

Experienced highness or lowness of a tone, dependent on frequency

Middle Ear

Chamber between the eardrum and cochlea containing three tiny bones

Cochlea

Coiled, fluid-filled tube in the inner ear that triggers nerve impulses from sound waves

Inner Ear

Innermost part of the ear, containing the cochlea and other structures

Sensorineural Hearing Loss

Hearing loss caused by damage to the cochlea's receptor cells or auditory nerves

Conduction Hearing Loss

Hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea

Cochlear Implant

Device for converting sounds into electrical signals to stimulate the auditory nerve

Place Theory

Theory that links the pitch we hear with the place where the cochlea's membrane is stimulated

Frequency Theory

Theory that the rate of nerve impulses matches the frequency of a tone, enabling us to sense its pitch

Gate Control Theory

Theory that the spinal cord contains a neurological gate that blocks pain signals

Kinesthesia

System for sensing the position and movement of individual body parts

Vestibular Sense

Sense of body movement and position, including balance

Sensory Interaction

Principle that one sense may influence another

Embodied Cognition

Influence of bodily sensations and states on cognitive preferences and judgments

Visual Cliff

a laboratory device for testing depth perception in infants and young animals

Gustav Fechner

Studied our awareness of faint stimuli and called in "absolute threshold"

Ernest Weber

Weber's Law; (he created/discovered it)

David Hubel

Studied the visual cortex of brain (cortical cells inside it) and how the cortical cells react to different stimuli

Torsten Wiesel

Significant for his discoveries concerning info processing in the visual system