Unit 3: Sensation and Perception

Prosopagnosia

inability to recognize familiar faces

Phonagnosia

inability to recognize familiar voices

Sensation

stimulations of a sense organ

Vision

the ability to see
Stimulus: light
Wavelength: hue
Amplitude: brightness
Transduction: retina

Audition

the ability to hear
Stimulus: sound waves
Wavelength: pitch
Amplitude: loudness
Transduction: cochlea

Gustation

the ability to taste
Stimulus: chemicals that dissolve in saliva
Transduction: tongue

Olfaction

the ability to smell
Stimulus: chemicals that evaporate in the air and dissolve in the muscus of your nose
Transduction: olfactory cilia

Tactation

the ability to touch
Stimulus: any energy that comes into contact with your skin

Sensory Receptors

sensory nerve endings that respond to stimuli

Perception

interpretation of sensory information

Bottom-Up Processing

looking at the different features of something and try to put it all together

Top-Down Processing

forming a general idea about something that alters or affects your preception

Sense Organs

eyes, ears, nose, skin, taste buds

Selective Attention

focus on one aspect of your environment (can lead to inintentional blindness)

Cocktail Party Effect

your ability to attend to only one voice among many

Inattentional Blindness

when you miss things you don't see

Inattentional Deafness

failing to hear an auditory message when attention is elsewhere

Change Blindness

failed to know a visual change in your enviornment

Change Deafness

failed to know auditory change in your environment

Popout

stimuli that draw our eye and demand our attention

Transduction

the process of turning an outside stimuli into neural impulses

Psychophysics

the study of how physical stimuli are translated into psychological experience

Absolute Threshold

minimum amount of energy that must be admitted from a stimulus to detect its presence

Signal Detection Theory

theory regarding how stimuli are detected under different conditions

Subliminal

below one's absolute threshold for conscious awareness

Difference Threshold (Just Noticeable Difference)

the smallest difference between two stimuli that can be detected 50% of the time is called

Weber's Law

a principle that states, for any change in a stimulus to be detected, a constant proportion of that stimulus must be added or subtracted

Sensory Adaptation

when you are exposed to a stimulus for so long you stop responding to it

Perceptual Set

a mental predisposition to perceive one thing and not another

Stroop Effect

the tendency to read the words instead of saying the color of ink

Schemas

a concept or framework that organizes and interprets information

Extrasensory Perception (ESP)

an ability to gain information by some means other than the ordinary senses

Parapsychology

the study of paranormal phenomena

Telepathy

mind to mind communication

Clairvoyance

being able to perceive events happening at the same time

Precognition

being able to predict something happening in the future

Psychokinesis (Telekinesis)

being able to move things with your mind

Wavelength

horizontal distance between two waves, gives the color, get longer as you move to the right

Hue

a particular shade of a given color

Amplitude

height of wave, tells us how bright the color will be

Intensity

the brightness or dullness of a color

Cornea

where light comes through, clear covering on your eye

Pupil

controls how much light enter your eye, an opening in your eye

Iris

controls how much light enters your eye, the colorful ring of muscle

Lens

bends the light that comes into your eye, to focus it on the retina

Retina

lining of neural tissue in the back of eye, absorbs light, processes the light into a neural impulse and sends them to the brain, made up of 7 cells

Accomodation

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

Nearsightedness (Myopia)

when your lens focus light too short from your retina (can't see far)

Farsightedness (Hyperopia)

when your lens focus too far from your retinas (can't see close)

Rods

night vision and peripheral vision, more sensitive in dark settings, 100 million rods, turn light into neural impulses to send back to the brain

Cones

color receptors that work in light settings, found in center of eye, 6 million cones, turn light into neural impulses to send back to the brain

Bipolar Cells

eye neurons that receive information from the retinal cells and distribute information to the ganglion cells

Ganglion Cells

the specialized cells which lie behind the bipolar cells whose axons form the optic nerve which takes the information to the brain

Optic Nerve

the nerve that carries neural impulses from the eye to the brain

Blind Spot (Optic Disc)

the point of nerve which the optic nerve leaves, known as blindspot

Fovea

the central focal point in the retina, around which the eye's cones cluster

Photoreceptors

respond to light

Optic Chiasm

point at which optic nerve fibers cross in the brain

Primary Visual Cortex

the region of the posterior occipital lobe whose primary input is from the visual system

Ventral Stream

what pathway, figure out what you are looking at (shape, color)

Dorsal Stream

where pathway, where is it in relation to you (how far, is it moving)

Young-Helmholtz Trichromatic Theory

3 types of color receptors for long, medium, and short wavelengths or light (red, green, blue)

Color-Deficient Vision

genetic disorder in which people are blind to green or red colors

Afterimages

a visual image persists after a stimulus is removed

Opponent-Process Theory

our color receptors make opposing responses to three pairs of colors

Feature Detectors

neurons that respond selectively to very specific features of more complex stimuli

Fusiform Face Area

a region in the temporal lobe of the brain that helps us recognize the people we know

Parallel Processing

the processing of many aspects of a problem simultaneously

Supercells

clusters of cells that respond to more complex patterns of visual information

Grandmother Cells

a hypothetical neuron that just responds to one particular stimulus

Blindsight

a condition in which a person can respond to a visual stimulus without consciously experiencing it

Gestalt

whole picture

Necker Cube

reversible figure, can see 7 faces of it

Reversible Figures

one sensation but two or more interpretations

Figure-Groud

organize our world in subjects and backgrounds, reverse between subject and background

Grouping

tendency to organize stimuli into coherent groups

Proximity

objects near each other seem to belong together

Continuity

we like things that are continuous

Closure

fill in missing lines

Similarity

objects that look like each other seem to belong together

Symmetry

we like things that are symmetrical

Past Experience

categorize things in terms of our prior experience

Common Fate

things that move in same direction seems to be part of one group

Pragnanz (Simplicity)

we perceive ambiguous and complex images in their simpler forms

Depth Perception

how we figure out how far away something is for us

Visual Cliff

involves an apparent, but not actual drop from one surface to another, originally created to test babies' depth perception

Binocular Cues

based on two eyes

Convergence

the way your eye muscle moves when things get closer/farther, closer makes eye muscles contract

Retinal Disparity

objects project slightly different images to each retina, as the object gets closer to you, the disparity gets larger

Monocular Cues

based on one eye

Relative Height

objects lower in our field of vision seem closer

Relative Size

objects closest to us look bigger

Interposition

objects closer to us may hide objects farther away

Relative Motion / Motion Parallax

objects closer to us move faster than objects far away

Linear Perspective

lines converge in the distance

Light and Shadow

light sources cast shadows to make things look like their coming away from us or towards us

Texture Gradient

objects closer to us has more texture

Relative Clarity

objects that are in sharp/focus are closer to us

Stoboscopic Movement

a series of slightly different images shown rapidly so it seems like continuous movement

Phi Phenomenon

illusion of movement when adjacent lights move on and off