Psychology: From Inquiry to Understanding Chapter 4

Illusion

Perception in which the way we see a stimulus doesn't match it's physical reality

Sensation

Detection of physical energy by sense organs, which then send information to the brain

Perception

The brains interpretation of raw sensory inputs

Transduction

The process of converting an external energy or substance into eletrical activity within neurons

Sense Receptor

Specialized cell responsible for converting external stimuli into neural activity for a specific sensory system

Sensory Adaptation

Activation is greatest when a stimulus is first detected

Psychophysics

The study of how we perceive sensory stimuli based on their physical characteristics

Absolute Threshold

Lowest level of a stimulus needed for the nervous system to detect a change 50% of the time

Just Noticeable Difference (JND)

The smallest change in the intensity of a stimulus that we can detect

Weber's Law

There is a constant proportional relationship between the JND and the original stimulus intensity

Synesthesia

A condition in which people experience cross-modal sensations

Selective Attention

Process of selecting one sensory channel and ignoring or minimizing others

Pupil

Hole through which light enters the eye

Cornea

Part of the eye containing transparent cells that focus light on the retina

Lens

Part of the eye that changes curvature to keep images in focus

Retina

Membrane at the back of the eye responsible for converting light into neural activity

Fovea

Central portion of the retina

Acuity

Sharpness of vision

Rods

Receptor cells of the retina that allow us to see in low levels of light

Cones

Receptor cells in the retina allowing us to see in color

Optic Nerve

Travles from the retina to the brain

Blind Spot

Part of the visual field we cannot see because of an absence of rods and cones

Feature Detector Cell

Cell that detects lines and edges

Trichromatic Theory

Idea that color vision is based on our sensitivity to three primary colors: blue, green and red

Opponet Process Theory

Theory that we perceive colors in terms of three pairs of opponent colors: either red or green, blue or yellow, or black and white

Cochlea

Bony, spiral-shaped sense organ used for hearing

Organ of Corti

Tissue containing the hair cells necessary for hearing

Basilar Membrane

Membrane supporting the organ of Corti and hair cells in the cochlea

Place Theory

Specific place along the basilar membrane matches a tone with a specific pitch

Frequency Theory

Rate at which neurons fire the action potential reproduces the pitch

Olfaction

Sense of smell

Gustation

Sense of taste

Taste Bud

Sense receptor in the tongue that responds to sweet, salty, bitter, unami (savory), and perhaps fat

Pheromone

Odorless chemical that serves as a social signal to members of one's species

Somatosensory

Our sense of touch, temperature, and pain

Gate Control Model

Idea that pain is blocked from consciousness by neural mechanisms in the spinal cord

Phantom Pain

Pain or discomfort felt in an amputated limb

Proprioception

Our sense of body position

Vestibular Sense

Our sense of equilibrium and balance

Semicircular Canals

Three fluid-filled canals in the inner ear responsible for our sense of balance

Processing

1)Parallel- the ability to attend to many sense modalities simultaneously
2)Bottom-Up- processing in which a whole is constructed from parts
3)Top-Down- conceptually driven processing influenced by belifs and expectancies

Perceptual Set

Set formed wheb expectations influence perceptions

Depth Perception

Ability to judge distance and 3D relations, by either monocular (one eye) or binocular (both eyes) depth cues

Subliminal Perception

Perception below the limen or threshold of conscious awareness

Extrasensory Perception (ESP)

Perception of events outside the known channels of sensation