AP Psych Unit 3: Sensation/Perception

How do we locate sounds?

Using two important auditory cues: which ear receives the sound first which ear receives a more intense sound Why are we not so good at locating sound that comes from ahead, behind, overhead or below us? Because the sound reaches our ears simultaneously this automatically causes us to turn our heads towards the sound

bottom-up processing

analysis that begins with the sensory receptors and works up to the brain's integration of sensory information occurs when our sensory receptors detect external stimulation and send the raw data to the brain for analyzing

somatosensory cortex

area at the front of the parietal lobes that registers and processes body touch and movement sensations

Transduction

conversion of one form of energy into another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brains can interpret.

conduction hearing loss

hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea SOUND CAN NOT GET THRU OUTER OR MIDDLE EAR Ex: pebble in ear, muffled

Interposition

if one object partially blocks our view of another, we perceive it as closer Tree blocking building, assumed that tree closer than building

relative size

if two objects are similar in size, we perceive the one that casts a smaller retinal image to be farther away

retinal disparity

images from the two eyes differ, and the closer the object the larger the disparity "Finger sausage"

sensory restriction

includes loss of a sense such as sight, resulting in increase perception in other senses

perceptual adaptation

means by which the brain accounts for the differences that the subject may witness, particularly alterations in the visual field. Example; displacement goggles, new glasses

cones

retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations. receptors that respond to light

rods

retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond receptors that respond to light

How the eye transforms light energy into neural messages

1. Light enters into the cornea ( protect eye and bends light) 2. Light passes through pupil (adjustable opening) surrounded by the iris, a colored muscle that adjust light intake and dilates / constricts to light intensity 3. The lens is behind the pupil to focus incoming light rays into an image onto the retina. 4. The optic nerve carries information to the brain to the thalamus to distribute. 5. A blind spot is created where the optic nerve leaves the eye, where there are no receptor cells. 6. Cones cluster in / around the vulva, the retinas area of central Focus.

How the ear transforms sound energy into neural messages

1. The ear transforms sound energy into neural messages, starting with the visible outer ear channeling sound waves through the auditory canal to the eardrum. 2. The middle ear then transmits eardrums vibrations through a piston of three bones (Hammer, Anvil, and stirrup) to the cochlea to the inner ear. 3. Incoming vibrations cause the cochlea, the oval window membrane, to vibrate so fluid that fills the semicircular canals. 4. This motion causes a ripple in the basilar membrane, bending hair cell linings. Hair cell movement triggers impulses in nerve cells, where axons converge to form the auditory nerve, sending neural messages (thalamus) to the temporal lobes auditory cortex.

linear perspective

A monocular cue for perceiving depth; the more parallel lines converge, the greater their perceived distance.

cocktail party effect

Ability to concentrate on one voice amongst a crowd situations that require direct attention

restored vision

After cataract surgery, blind adults were able to regain sight. These individuals could differentiate figure and ground relationships, yet they had difficulty distinguishing a circle and a triangle

Ponzo illusion

An illusion of size in which two objects of equal size that are positioned between two converging lines appear to be different in size. Also called the railroad track illusion.

Schemas

Concepts or mental frameworks that organize and interpret information.

How is our perception of pain a biopsychosocial phenomenon?

Biological: When distracted from pain, the body is soothed by a release of endorphins (natural painkillers) Sociocultural: Pain varies with social situation and cultural traditions. We experience pain when everyone else is as empathy mirrors pain for ourselves Pain: the body's way of telling you something is wrong and a behavior change is necessary Editing memories of pain, transforming what we actually experienced causes an overlooking of pain duration Recording a pain's peak moment when it was at its most unbearable Registering how the pain felt at the end, forgetting the peak

top-down processing

Information processing guided by high level mental processes When we construct perceptions drawing on our past experiences and expectations Sensitivity to sound- baby crying- baby sad/needs assistance the use of preexisting knowledge to organize individual features into a unified whole

How can perception be viewed as a biopsychosocial phenomenon?

Is perception innate or acquired? (version of reality) Biological: - entry level sensory analysis - unlearned visual phenomena - critical period of sensory development Psychological: - selective attention - learned schemas - Gestalt principles - emotional context effects - perceptual sets Social-cultural: - cultural assumptions/expectations - physical context effects

How do we sense our touch/body's position and movement?

Our sense of touch is controlled by a huge network of nerve endings and touch receptors in the skin known as the somatosensory system. This system is responsible for all the sensations we feel - cold, hot, smooth, rough, pressure, tickle, itch, pain, vibrations, and more. 1. Starts off as signals generated by touch receptors that travel along sensory nerves connected to neurons in the spinal cord 2. Move to the hypothalamus where the info is spread 3. The last place is the somatosensory cortex where the signals turn into perceived touch 4. The most sensitive areas like the lips stimulate a larger area of the cortex

Sensation vs. perception

Sensation: the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment Perception: the process of organizing/interpreting sensory information, enabling us to recognize meaningful objects/events Sensation is arrival of info to brain (basic intake), perception is interpretation of info in brain (add meaning)

How do we experience smell?

Smell, or olfaction, happens when chemicals in the air enter the nose during the breathing process. Smell receptors lie in the top of the nasal passage. They send impulses along the olfactory nerve to the olfactory bulb at the base of the brain.

Parallel processing- brain processing visual information

The processing of many aspects of a problem simultaneously Serial (step-by-step) processing of computers The brain can simultaneously process different aspects of stimuli such as motion, shape, and depth; this helps the brain paint a full picture of the scenario

opponent process theory of color vision

Theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision. -Some cells are stimulated by green and inhibited by red -Some cells are stimulated by red and inhibited by green -Explains why neurons are stimulated for certain colors and not others the theory that receptor cells for color are linked in pairs, working in opposition to each other

trichromatic theory of color vision

Theory that the retina has 3 color receptors (red, green, and blue) which, when stimulated together can produce the perception of any color

How do we experience taste?

These receptor cells, or taste buds, bind with molecules from the food or drink being consumed and send signals to the brain. The way our brains perceive these stimuli is what we refer to as taste, with there being five recognised basic tastes: salty, bitter, sweet, sour and umami (meat, savory)

Gestalt Psychology

a psychological approach that emphasizes a figure formed a "whole" different than its surroundings ("The whole is greater than the sum of its parts")

signal detection theory

a theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). Assumes there is no single absolute threshold and that detection depends partly on a person's experience, expectations, motivation, and alertness. false alarms old car, convince ourselves we hear "clunks"

pitch

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

monocular cues

depth cues, such as interposition and linear perspective, using 1 eye relative size

binocular cues

depth cues, such as retinal disparity, that depend on the use of two eyes retinal disparity

sensory adaptation

diminished sensitivity as a consequence of constant stimulation Example; forgetting watch is on wrist, can't feel it unless mentioned Reduced sensitivity, freedom to focus on information changes in our environment w/o being distracted by uninformative background stimulation

ESP

extrasensory perception; the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition

change blindness

failing to notice changes in the environment Example: guy asking for directions, switches places w/ another after interruption of a wood board passing by, person doesn't realize their talking to a new guy because he fits the basic criteria

inattentional blindness

failing to see visible objects when our attention is directed elsewhere

perceptual constancy

perceiving objects as unchanging (having consistent lightness, color, shape, and size) even as illumination and retinal images change Knowing from the nose-bleed seats that the players on the field are human-sized even though from far away they look miniature Shadow over newspaper but newspaper isn't black

Volley theory of pitch perception

states that groups of neurons of the auditory system respond to a sound by firing action potentials slightly out of phase with one another so that when combined, a greater frequency of sound can be encoded and sent to the brain to be analyzed.

Detection- - brain processing visual information

the ability to determine the presence of an object

depth perception

the ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance

priming

the activation, often unconsciously, of certain associations, thus predisposing one's perception, memory, or response Example: if a child sees a bag of candy next to a red bench, they might begin looking for or thinking about candy the next time they see a bench

Intensity

the amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave's amplitude (height)

Fovea

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

hue

the dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, and so forth

Wavelength

the distance from the peak of one light wave to the peak of the next

selective attention

the focusing of conscious awareness on a particular stimulus, as in the cocktail party effect

Amplitude

the height of a wave's crest determines volume

difference threshold

the minimum difference between two stimuli required for detection 50 percent of the time "just noticeable difference" For example, if you were asked to hold two objects of different weights, the just noticeable difference would be the minimum weight difference between the two that you could sense half of the time.

absolute threshold

the minimum stimulation needed to detect a particular stimulus 50 percent of the time, necessary to detect light, sound, pressure, taste and odor Example: see a candle burning from miles away Smell 1 singular drop of perfume in a three bedroom apartment

sensorineural hearing loss

the most common form of hearing loss, also called nerve deafness; caused by damage to the cochlea's receptor cells or to the auditory nerves INNER EAR DAMAGE Example: caused by excessive noise exposure

frequency theory of pitch perception

the nerve impulses that travel up the auditory nerve, which sends information about sound to the brain, have the same rate as the frequency of the tone you are hearing the basilar membrane receives the sound wave and starts vibrating, this causes neural impulses moving along the brain at the same pace as the sound wave

Frequency

the number of complete wavelengths that pass a point in a given time measured in Hertz (Hz) determines the pitch ( tone's high or lowness) of the sound.

figure-ground

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

grouping

the perceptual tendency to organize stimuli into coherent groups

blind spot

the point at which the optic nerve leaves the eye, creating a "blind" spot because no photoreceptor cells are located there When both eyes are open blind spots can not be detected and even when one eye is closed the brain still does a good job of "covering up" the areas that can not form image detection It is located where blood vessels have major entry points to the eye that are utilized by the retina

perceptual set

the predisposition or 'readiness' to perceive something in accordance with what we expect it to be. often referred to as expectancy because various psychological factors (such prior experience and context) create an expectation to perceive information in a particular way. Expecting to see young woman, don't see old woman until it is pointed out

sensory interaction

the principle that one sense may influence another, as when the smell of food influences its taste

Weber's Law

the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount) Adding 1 pound to 10 pounds is noticeable Adding 1 pound to 100 pounds is less noticeable

accommodation

the process by which the eye's lens changes shape to focus near or far objects on the retina Lens flattens when focusing on distant objects Lens rounds when focusing on nearby objects

vestibular sense

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

Psychophysics

the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them

gate-control theory

the theory that the spinal cord 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 up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain. Example: rubbing area around stubbed toe blocks some pain messages

place theory of pitch perception

the way we hear sound is determined by the location of the vibrations produced by the frequency within the cochlea's basilar membrane

Gibson and Walk's Visual Cliff

to measure infants ability to perceive depth; most infants older than 6 months will not crawl out over the deep side, indicating that they can perceive depth

closure

we fill in gaps to create a complete, whole object

relative height

we perceive objects higher in our field of vision as farther away than those that are lower

subliminal threshold

when stimuli are below one's absolute threshold for conscious awareness a. we can unconsciously sense (literally=below) b. w/o awareness, stimulis= suggestive powers, detected 1/2 the time

kinesthesis

your sense of the position and movement of your individual body parts example: being able to sense the position of your limbs during the night