ap psych unit 3

short wavelength _ high frequency

long wavelength = low frequency

acuity-sharpness of vision

cornea- transparent tissue in the front of your,rays of light entering the eye are bent first by the curved cornea

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 (colored part of the eye)

pupil - the adjustable opening in the center of the eye through which light enters ( black part of the eye)

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 begin the process of vital information.

visual accommodation - the change in the thickness(shape) of the lens as the eye focuses on objects that are faraway or close

transduction occurs in the retina

cones- light detecting cells that are concentrated near the center of the retina and that function in daylight or in well lit conditions

color consistency- perceiving familiar objects as having consistent color, even if changing illumination layers the wavelengths reflected by the object

depth perception- ability to see objects in three dimensions

allows us to judge distance

binocular cues- retinal disparity, images from the two eyes differ (your two eyes seeing the same thing but a little different ) closer the object the larger the disparity.

convergence (also a binocular cue) - neuromuscular cue two eyes move inward for near objects

rods- specialized photo receptors that work well in low light conditions, involved in our vision in dimly lit environments as well as in our perception of movement on the periphery of our visual field

monocular cues- relative size smaller image is more distant

interposition ( monocular cue)- closer object blocks distant object

relative clarity (monocular cue)- lazy object seen as more distant

texture (monocular cue)- coarse--> closifine

relative height (monocular cue)- higher object seen as more distant

relative motion (Monocular cue)- closer object seem to move faster

linear perspective (monocular cue)- parallel lines converge with distance

relative brightness (monocular cue) - closer objects appear brighter

visual capture- your most dominate sense

proximity- group nearby figures together

similarity- grouping figures that are similar

continuity - perceive continuous patterns

closure- fill in gaps

connectedness - spots lines and areas ares seen as a unit when connected

Opponent-Process Theory: The theory that opposing retinal processes (red green, yellow-blue, white-black) enable color vision. Some cells of the visual system are excited by one of the opponent colors and inhibited by the other

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The brain takes in information to make a series of interpretations that allow us to see what we see\

Feature Detectors: In the visual cortex, specialized neurons that react to the strength of visual stimuli, responding to shapes, angles, edges, lines and movement in field of vision

Parallel Processing: The ability of the brain to do many things at once. For visual processing, color, motion, shape, and depth are processed simultaneously

Optic Nerve: The nerve that carries neural impulses from the eye to the brain (cross to opposite side of brain, once inside the brain, visual information is sent via a number of structures to the occipital lobe at the back of the brain for processing)

perceptual constancy - perceiving objects as unchanging even as illumination and retinal image change

perceptual set- a mental predisposition to perceive on thing and not another

muller- lyer illusion-

hearing

outer ear - conducts sound waves into ear

ear canal/auditory canal - where sound waves are directed to the middle of the ear

middle ear- where sound waves are transformed into vibrations

inner ear- transforms sound waves into electrical impulses

ear drum - vibrations in the ear

anvil- bones in ear that helps us hear

stirrup- receives sound vibrations from anvil

cochlea- sense of hearing that helps process auditory transduction

pinna- part of ear that you can see

auditory nerves- nerves that transmit sound the the brain

transduction of sound - occurs in the corti - process of converting sound waves into neural impulses

amplitude and intensity- how loud sound is

pitch theory/place theory- links the pitch we hear with its location in he cochlea

frequency/match theory- rate of impulse matches to one frequency

frequency -

timbre- the quality of auditory sensation that is distinguished by sound waves

basilar membrane- located in the cochlea’s hair cells

semicircular canal- helps keep you balanced

sUnit 3 - Sensation & Perception Sensation Sensation - all information coming in to our brain from our sensory receivers (objective) Light waves, sound waves, etc. Perception - Our understanding of those sensations (subjective) Sensation without perception - Prosopagnosia - face blindness Brain cannot make sense of a face Transduction - physical energy into a neural impulse Psychophysics - study of our interpretation of sensory information 7 Senses Seeing - Vision (transduction takes place in the retina) Hearing - Audition (transduction takes place in the cochlea) Tasting - Gustation (transduction takes place on the taste buds) Smelling - Olfaction (transduction takes place on the olfactory receptors) Touch - Tactition/somatosensation (transduction takes place in the sensory receptors on the skin) Balance - Vestibular/vestibulation (transduction takes place in the semicircular canals) Body sense - Kinesthetic (transduction takes place in the proprioceptors/sensors in joints) The Eye Stimulus - light energy (waves) Feature detection - visual association area - different cells in the visual cortex pick up different angles, edge, movement, etc. Process of light entering eye: Cornea - clear, protective outer layer Pupil - adjustable opening in the center of the eye; light enters Iris - colored area around eye (muscle) that dilates or contracts pupil Lens - behind the pupil; bends to focus light on retina (accommodation) Lens flips light image upside-down Retina - light sensitive inner surface of the eye Fovea - area on retina where light is focused (cones are clustered here) Transduction on the retina: Photoreceptors (rods - black and white, dim lighting; or cones - color, detail) pick up light signals Bipolar cells - action potential triggered by light waves picked up by photoreceptors (transduction) Ganglion cells - connect with bipolar cells; axons twine together to form optic nerve Optic nerve - nerve that carries neural impulses from eye to brain Blindspot - area where optic nerve leaves the eye (no photoreceptors) Visual perception: Optic nerves carry message (cross at optic chiasm) Pass through thalamus Visual perception occurs in visual cortex of occipital lobe Color Vision Young & Helmholtz Trichromatic Theory - retina Three light-sensitive photoreceptors in retina - red, blue, and green Combination of these photoreceptors stimulated creates different color messages Does not explain afterimages Opponent-Process Theory - optic nerve Ganglion cells that have opposing color signals (action potentials) Red/green Blue/yellow Black/white One color is stimulated, opposing color is turned off Afterimages Hearing Process of sound waves entering ear: Enter through auditory canal Vibrate tympanic membrane (eardrum) Vibrate bones of the middle ear (malleus/hammer, incus/anvil, stapes/stirrup) Vibrate causes oval window (opening to cochlea) to open Process of transduction Fluid in cochlea vibrates Fluid vibration causes hair cells (cilia) on basilar membrane to bend - different areas of the cochlea react to different sound waves Stimulated hair cells cause neural signal in auditory nerve Auditory perception: Auditory nerve stimulated by hair cells Signal travel through thalamus Routed to auditory cortex of temporal lobe Sound waves Amplitude (high or low) - loudness Pitch (wavelengh) -- low pitch is wide wavelength (low frequency); high pitch is short wavelength (high frequency) Deafness Conduction deafness - bones in middle ear start to deteriorate Can get hearing aid Sensorineural (nerve) deafness - hair cells in cochlea deteriorate Cochlear implant Touch 4 types of sensory receptors - cold, warmth, pressure, and pain Sends signal to somatosensory cortex Pain - Gate-control theory Small nerve fibers conduct pain signals to brain Activating large nerve fibers (competing stimulation) can close the pain gates and block signal Endorphins Phantom limbs - feeling perception of touch in areas that are no longer there Area of the brain still exists Smell (chemical sense) Smell chemicals enter nose and activate olfactory receptors connected to olfactory bulb Smell connected with memory - proximity of olfactory bulb to hippocampus Taste (chemical sense) Taste buds send signals to brain 5 types of taste - sweet, salty, bitter, sour, and umami (savory) Vestibular sense Sense of balance Transduction occurs in semicircular canals in middle ear Kinesthetic sense Body positioning Receptors located in our muscle and joints (proprioceptors) Sensory interaction Senses often interconnected - one sense can effect another sense Smell and taste = flavor Color of something can influence how we think it tastes (Froot Loops) Sensory adaptation If our sensory receptors are exposed to continued stimulation for too long, they will start to ignore it Wearing a watch Bad smells Perception Our understanding of the world around us - how we make things meaningful to us Bottom Up vs Top Down Processing Bottom up processing - sensation followed by perception (build up to higher-level processing) Sensation (body) is BELOW perception (brain/mind) Use in new situations - babies putting things in their mouth to understand Top down processing - using previous experience and expectations to create a perception of the situation Perception (brain/mind) ABOVE sensation (body) Stereotypes - fit previous experiences into something new to create perception Ability to do things with little thought - you can get around your room in the dark relatively easily because of your previous experience in your room MOST IMPORTANT CONCEPT IN THE CLASS Sensation into Perception Thresholds Absolute threshold - minimum amount of stimulation sensory receptors need to send message to the brain to be perceived (when no competing stimuli is present) Exact same thing as neural threshold - have to have enough neurons fire for the signal to reach the brain If you whisper something and I don’t hear you, it wasn’t loud enough to reach my absolute threshold Subliminal messaging - used in advertising - presenting messages below our conscious level (subconscious still picks it up) Little evidence that it works in advertising - subliminal smells do seem to influence perception though Difference threshold - minimum amount of change needed in a stimulus for us to notice that there has been a change Weber’s law (just-noticeable difference) - perception of difference differs by a constant percentage Weight - 2% change in weight to notice that something has gotten heavier Really only works with weight Selective Attention - what we perceive is never absolute; very dependent upon what our expectations are/what we are paying attention to (top down processing) Cocktail party effect - ability to focus on one voice in a loud room Inattentional blindness - we do not notice small changes in our environment because our attention is elsewhere Change blindness - will not notice small changes in our environment if we are not looking for them Signal detection theory - what we notice is dependent upon what we expect/how alert we are/what our motivations are/etc. (no single absolute threshold) Example: As teachers, we might be more likely to notice a problem student being on their phone rather than a student who is well-behaved Perceptual Organization Perceptual adaptation Ability for brain to filter out distractions (especially in the visual field) Cocktail party effect Inversion goggles Gestalt - rather than seeing individual parts, the brain organizes things into meaningful wholes - used alot in art, architecture, and web design Proximity - we tend to group nearby figures together People sitting next to each other Similarity - we group things together that are similar Uniforms for teams Continuity - we tend to perceive continuous patterns (eye follows the smoothest path) Items in a row on the “suggested” part of Amazon Closure - we tend to fill in gaps in visual and auditory information Leaving out a note while whistling - brain fills it in Connectedness - we tend to group things that are connected People holding hands are a couple Figure-ground relationship - what we are focusing on is the figure, everything else is the ground (background) Cocktail party effect Boat on the ocean Depth Perception Visual capture Vision dominates all other senses McGurk effect Rubber hand illusion Visual cliff - experiment done to see if babies could perceive depth Able to by about 3 months Binocular cues (two eyes) - biological - each eye sees a slightly different image, and then the brain puts the two images together (how 3D vision works) Retinal disparity - larger the difference between the two retinal images, the closer the object Convergence - the more the eye muscles pull the eyes inward to look at something, the closer the object Monocular cues (one eye) - environmental - only need one eye to use these cues (often used in art) Relative size - smaller objects are seen as further way (if they are similar) Interposition - when one object is blocking another object, it is perceived as being closer Relative clarity - blurry or hazy objects are perceived as being further away Texture gradient - objects that more detail are perceived as being closer Relative height - objects that are higher in the visual field are perceived as being further away Linear perspective - parallel lines appear to converge in the distance once they reach the horizon Motion parallax - objects that are closer appear to move faster than objects that are further away Light and shadow (relative brightness) - objects that are reflecting more light (are brighter) are perceived to closer than darker objects Perceptual set - predisposed to think one thing over another Priming Signal detection theory Context effects Perceptual constancies - perceiving objects as unchanging even when the retinal image changes Shape Size Color