CHAP 6 MYERS- omg u can see??

sensation

sensation

the process by which our sensory receptors and nervous system receives and represents stimulus energies from our environment

perception

the process of organizing and interpreting sensory info enabling us to recognize meaningful objects and events

bottom-up processing

analysis that begins with the sensory receptors and works up to the brains integration of sensory info

top down processing

information process guided by higher level mental processes as when we construct perceptions drawing on our experiences and expectations

transduction

conversion of one form of energy into another. in sensation, the transforming of stim energies, such as sights, sounds and smells —> neural impulses our brain can interpret

psychophysics

the study of relationships such as their intensity, and our psychological experience of them

all our senses…..

• receive sensory stim, often using specialized receptor cells

• transform that stim into neural impulses

• deliver neural info to our brain

signal detection theory

a theory predicting how and when we detect the presence of a faint stim (signal) amid background stim (noise). Assumes there is no single absolute threshold and that detection depends partly on a person’s experience, expectations, motivation, and alertness

subliminal

below one’s absolute threshold for conscious awareness

priming

the activation, often unconscious, of certain associations, thus predisposing one’s perception/memory/response

difference threshold

the minimum difference between diff stimuli for detection 50% of the time. we experience the diff threshold as just a noticeable diff

weber’s law

• Definition: A principle in psychology that states the just noticeable difference (JND) between two stimuli is proportional to the magnitude of the original stimulus.

• Example: If you have a 10-pound weight and add 1 pound, you may not notice the difference. However, if you have a 100-pound weight and add 1 pound, you are more likely to notice the change.

• Key concept: Weber's Law helps explain how our perception of stimuli changes based on their initial intensity.

sensory adaptation

diminished sensitivity as a result of constant stim

perceptual set

a mental predisposition to perceive one thing and not another

sensory adaptation allows for…..

freedom to focus on informative changes in our environment without being distracted by chatter

we see the world…..

not as it is, but as it is useful for us to perceive it

perceptual set example:

when shown ambiguous images, our perceptual set can influence how we interpret them, leading to different perceptions among individuals.

wavelength

the distance from the peak of one light/sound wave to the peak of the next. Electromagnetic wavelengths vary from short blips of cosmic rays to long radio transmission waves

hue

the dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, red, etc..

intensity

the amount of energy in a light/sound wave, which we perceive as brightness/loudness, as determined by the waves amplitude

pupil

the adjustable opening in the center of the eye thru which light enters

iris

a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening

lens

the transparent structure behind the pupil that changes shape to help focus images on the retina

retina

the light sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begins the processing of visual info

accommodation

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

rods

retinal receptors thst detect black, white, and gray; necessary for twilight and peripheral vision

cones

retinal receptor cells that are concentrated near the center of the retina and that func in daylight/well lit conditions. cones detect fine details and give rise to color sensations

optic nerve

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

blind spot

the point at which the optic nerve leaves the eye, creating a “blind” spot bc no receptor cells are located there

how the eye processes creates vision

• cornea protects the eye & bends light to provide focus

  • light then passes thru the pupil

    • iris controls size (thru dilation)

      • lens focuses incoming light rays onto an image on the retina

  • the retina receives pieces of info which is eventually perceived by the brain

fovea

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

each cone transmits to….

a single bipolar cell that relays the cone’s individual message to the visual cortex

after processing, info travels from…..

bipolar cells—>ganglion cells—> axons of the optic nerve

even _______ can trigger retinal cells

pressure

feature detectors

nerve cells in the brain that respond to specific features of the stimulus (ie shape, angle, movement)

• feature detector cells respond to a scene’s specific features (particular lines, edges, angles, & movements)

parallel processing

the processing of many aspects of a problem simultaneously; the brain’s natural mode of info processing for many funcs, including vision. contrasts the step by step (serial) processing of most computers/conscious problem solving

young-helmholtz trichromatic theory

the theory that the retina contains 3 diff color receptors - 1 most sensitive to red and likewise for green and blue; which, when stimmed in combination, can produce the perception of any color

opponent process theory

the theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision.

• ex: some cells are stimulated by green and inhibited by red (and vice versa)

gestalt

an organized whole. gestalt psychologists emphasized our tendency to integrate pieces of info into meaningful wholes

figure-ground

the organization of the visual field into objects (figures) that stand out from their surroundings (the ground)

grouping

the perceptual tendency to organize stimuli into coherent groups

proximity

grouping of nearby objects together

continuity

perception of smooth continuous patterns rather than discontinuous ones

ex: seeing a wavy line split by a straight line rather then alternating semicircles

closure

filling in gaps to create a compete, whole object

depth perception

the ability to see objects in 3D although the images that strike the retina are in 2D; allows us to judge distance

visual cliff

a lab device for testing depth perception in infants/young animals

binocular cues

a binocular cue for perceiving depth; done by comparing images from the retinas in the two eyes—> brain computes distance (the greater the disparity the closer the object)

relative height

perception of objects higher in the field of vision as further away

relative motion

as we move, objects that are actually stable may appear to move

relative size

if we assume 2 objects are similar in size, most people will assume that the one that casts the smaller retinal image is further away

interposition

if one object partially blocks our view of another, we perceive it as closer

linear perspective

parallel lines appear to meet in the distance. the sharper the angle of convergence the greater the perceived distance

light and shadow

shading produces a sense of depth consistent with our assumption that light comes from above

monocular cues

depth cues, such as interposition & linear perspective, available to either eye alone

phi phenomenon

an illusion of movement created when 2+ adjacent lights blink on and off in quick succession

perceptual constancy

perceiving objects as unchanging (having constant shapes, sizes, brightness, colors, etc) even as illumination and retinal images change

color constancy

perceiving familiar objects as having constant color, even if changing illumination alters the wavelengths reflected by the object

perceptual adaptation

in vision, the ability to adjust to an artificially displaced or inverted visual field

audition

the sense/act of hearing

frequency

the number of complete wavelengths that pass a pt in a given time (ie per sec)

pitch

a tone’s experienced highness or lowness; depends on frequency

middle ear

the chamber between the eardrum and the cochlea containing three tiny bones (hammer, anvil, stirrup) that concentrate the vibrations of the eardrum on the cochlea’s oval window

cochlea

a coiled, bony, fluid-filled tube in the inner ear; sound waves traveling thru the cochlear fluid trigger nerve impulses

inner ear

the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs

sensorineural hearing loss

hearing loss caused by damage to the cochlea’s receptor cells/to the auditory nerves (aka nerve deafness)

condition deafness

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

cochlear implant

a device for converting sounds into electrical signals and stimulating the auditory nerve thru electrodes threaded into the cochlea

place theory

in hearing, the theory that links the pitch we hear with the place where the cochlea’s membrane is stimulated - tells us how we sense high pitches

frequency theory

the theory that the rate of nerve impulses traveling up the auditory nerves matches the frequency of a tone, thus enabling us to sense its pitch- tells how we sense low pitches

by firing in….

rapid succession, neural cells can achieve a combined frequency of over 1000 waves/sec

nociceptors

sensory receptors that detect harmful/hurtful temps, pressures, chemicals, etc

gate control theory

the theory that the spinal chord contains a neurological “gate” that blocks pain signals or allows them to pass on to the brain. the “gate” is opened by the activity of pain signals traveling uo small nerve fibers and is closed by activity in larger fibers or by info coming from the brain

personal experience of pain: biological

• activity in the spinal chord’s large and small fibers

• genetic differences in endorphin production

• the brain’s interpretation of CNS activity

personal experience of pain: sociocultural

• presence of others

• empathy for other’s pain

• cultural expectations

personal experience of pain: psychological

• attention to pain

• learning based on experience

• expectations

embodied cognition

in psychological science the influence of bodily sensations, gestures, and other states on cognitive preferences and judgements

kinesthesis

the system for sensing the position and movement of individual body parts

vestibular sense

the sense of body movement and position, including the sense of balance

clairvoyance

perceiving remote events, such as a house on fire in another state

precognition

perceiving future events, such as an unexpected death in the next month

ESP (extra sensory perception)

the controversial claim that perception can occur apart form sensory input (includes telepathy, clairvoyance, and precognition)

parapsychology

the study of paranormal phenomena, including ESP an psychokinesis

influences on our perception of reality: biological

• sensory analysis

• unlearned visual phenomena

• critical per for sensory development

influences on our perception of reality: psychological

• selective attention

• learned schemas

• gestalt principles

• context effects

• perceptual set

influences on our perception of reality: sociocultural

• cultural assumptions and expectations