Sensation and Perception

Term Explanation Application/Example/Extension

n Sensation is the process of using senses to detect or sense Your eyes detect light waves, your ears detect sound waves, o i

t information from the environment your skin detects pressure a s Processes Bottom-up processing is an information Remember information is sent from the bottom up to the n

e of processing the begins with the senses and then brain. S

Sensation goes to the brain

Transduction is the process of converting The brain communicates with the body through neural

physical energy from the environment into communication by utilizing action potentials and the release

neural code to be interpreted by the brain of neurotransmitters.

Absolute threshold is the minimum An action potential cannot occur until there is a minimum

stimulation necessary to detect an amount of stimulation necessary that exceeds the threshold-

environmental stimulus this depends on the strength of the stimulus

Difference threshold- also called the just In order to detect a difference between a person’s voice and

noticeable difference- is the minimum the background noise of a classroom, there has to be enough

difference that is needed to detect a difference of a difference or you will not be able to hear the person

between 2 stimuli talking.

Weber’s law states in order to If the classroom noise gets louder then by proportion, so

detect a difference between 2 does the person’s voice, in order to compete with the

stimuli, then the stimuli must differ increase of the classroom noise. A teacher has to talk louder

by a constant proportion to compete with the nose of the classroom.

Signal detection theory is a set of formulas If a student is to detect a teacher’s voice, then the teacher’s

which predicts that we can detect a stimulus voice has to be (1) loud enough, or exceed the absolute depending on the strength of the stimulus, the threshold, the (2) the classroom noise, or environment has to environment, and person detecting the be in proportion to the teacher’s voice (cannot be louder to stimulus the teacher’s voice), and (3) the student has to be focused on the teacher’s voice through being motivated to listen. Selection attention is focusing attention on the particular stimulus Sensory adaptation is diminished sensitivity as a When you first jump into a pool it is cold, then over a result of constant exposure to stimulus period of time, or constant exposure to the water, the person’s senses adapt to the cool temperature of the water. (The temperature of the water did not change- the senses adapted- or got used to the water temperature)

Submitted by Mike McLane, Sterling Heights High School, Michigan: Permission to use for face-to-face instruction with students only. Sensation and Perception e e Hue refers to color, which is Wavelength- is indicated from Long Medium Short S

e determined by the length of a one peak of a wave to the wavelengths wavelengths wavelengths w

t wave. following peak produce reddish produce greenish produce bluish a

h colors colors colors W

Intensity, or brightness of a color, is determined by the height of a wave, referred to as amplitude

Great amplitude or taller waves produce brighter colors The taller the wave the brighter the color. Think about

staring up at a roller coaster- the higher you look up, the brighter it gets Small amplitude or smaller waves produce dull colors e y Parts of Cornea protects the eye and begins to bend light waves E the Eye e Iris is the colored portion of the eye that controls The iris constricts, which When it is dark out the iris h the size of pupil makes the size of the pupil expands, allowing more T

smaller, in response to light to enter the pupil

Pupil- is the opening in the eye that

bright light because too therefore allowing enough

allows light to enter

much light entering the stimulation to exceed the

pupil at once could threshold and cause an

damage the retina. action potential

Lens is the part of an eye that focuses on an object The lens is like a camera

Accommodation refers to the process of

how the lens focuses in and out of an object

Retina is the part of an eye where the process of transduction takes place through the use of the sensory

receptors rods and cones (referred to as photoreceptors)

Rods are receptor cells that are stimulated Rods react to stimulation much slower than cones,

in dim light or dark conditions; peripheral which is why it takes longer to see objects in the dark.

vision Rods also don’t detect fine details, which is why you just see the image of an object in the dark Cones, located in the fovea, are stimulated, The fovea, where cones are stored, is in the center of the or turned on, in response to color and fine eye, which is why a person stares straight at an object to details detect little details. Bipolar cells gather information from the rods and cones and pass the information to the ganglion cells Ganglion cells are bundles of axons that form the optic nerve, which sends information to the brain

Submitted by Mike McLane, Sterling Heights High School, Michigan: Permission to use for face-to-face instruction with students only. Sensation and Perception

Blind spot is where the optic nerve exits the You don’t detect this blind spot because both of your back of the retina, which causes a blind spot eyes accommodate for what the other eye does not in the visual field detect Optic chiasm- refers to the area of the brain The left part of the retina sends information through an where the optic nerves cross optic nerve that carries the information to the right side of the brain where the primary visual cortex processes the information and the right part of the retina sends information to the left side of the brain Feature detectors- are specialized cells that Think about using feature detectors to watch a motion- process specific visual features like shape, size, and feature presentation- (movie) angle of a stimulus

r Theories Trichromatic theory When a person Red sensitive cones detect long wavelengths- think of o l o of color developed by Young- can’t see red, for Clifford the dog C

n vision Helmholtz- states that we have example, it could Blue sensitive cones detect short wavelengths- think of o

i

s 3 different types of cones, each be because he or i Smurfs

v

sensitive to particular type of she does not have Green sensitive cones detect medium wavelengths- think

light wave, and through red sensitive

of leprechauns

combinations of these cones cones being stimulated, we see color Opponent-process theory suggests that color is When a red cone is activated, then the green cone is off, processed through pairs- red-green, blue-yellow, which is why we don’t describe color as reddish- black-white greenish. Also if you stare at a red dot for a while, then look away you will see a green dot, which is referred to as an afterimage.

What we Sound is the result of repetitive fluctuations of Sound waves, unlike light wavelengths, can travel

Hear sound waves hitting, or bumping, into a medium through objects- you can hear underwater, but because

like air. the sound waves bounce, or hit the water the sound of a n

o i

stimulus is altered. Your mother’s voice does not sound t i

d the same underwater as it would if you were talking to g u n i

A her in your room.

r

a

e Frequency refers to the number of complete wavelengths that pass a point

H Pitch refers to the highness or lowness of a sound, which depends on frequency

Submitted by Mike McLane, Sterling Heights High School, Michigan: Permission to use for face-to-face instruction with students only. Sensation and Perception

Loudness depends on amplitude, which is the Loudness is similar to brightness- the taller the wave the

height of a wave- this is measured in decibels louder the sound, the smaller the wave, the softer the

sound

Timbre is the complexity of a sound comprised of different frequencies and amplitudes.

Parts of Outer ear contains the visible outer ear and the Your outer ear is shaped the way it is to be able to best the Ear auditory canal. As sound waves enter the outer ear detect sound waves they are channeled to the eardrum. From the eardrum, the vibrations are sent to the middle ear. Middle ear, located between the eardrum and the Remember People who have damage to the middle cochlea is considered the mechanical portion of the the middle ear ear, which is referred to as the ear and contains 3 tiny bones (hammer, anvil, HAS mechanical portion of the ear, stirrup) that amplify sound waves and send then to (hammer, experience conduction hearing loss. the inner ear anvil, stirrup) People with this type of hearing loss 3 tiny bones can benefit from a mechanical hearing aid, which does the job of the damaged middle ear Inner ear, specifically the cochlea (part of the People who have damage to inner ear, called inner ear) is where transduction takes place sensorineural hearing loss, often have permanent damage Cochlea is a coiled, fluid-filled bony tube lined by the basilar membrane Basilar membrane is the surface, or lining, of the cochlea. When the basilar membrane begins to move as a result of incoming vibrations, then the cilia begins to move. Cilia- hair cells on the membrane that Think of cilia as tall grass- you can tell how windy it is when moving cause neural impulses to by how fast the tall grass is moving- the faster the cilia travel up the auditory nerve to the brain moves, the louder the sound Audition Place theory- what we hear depends on the place The place theory is similar to playing a guitar, where Theories the vibration strikes the basilar membrane- higher you place your finger on the guitar chord will produce a frequencies at the beginning and low frequencies different sound- same in terms of where the vibration towards the end strikes the basilar membrane

Submitted by Mike McLane, Sterling Heights High School, Michigan: Permission to use for face-to-face instruction with students only. Sensation and Perception

Frequency theory, also called Volley Principle- The frequency theory can be compared to shaking a rug- what we hear depends on the rate the impulse the harder you shake the rug, the more dust will come travels up the auditory nerve- higher frequencies off- the higher the frequency, the faster the impulse will faster rate travel up the auditory nerve e

t Taste is a chemical sense, containing the taste bud receptor Babies have a biological predisposition to like salty and s a

t cells, sweet, salty, sour, bitter, which are located on the sweet tastes making it more likely to like breast milk, t a tongue. Each taste bud is sensitive to particular types of food which is a combination of these taste buds. On the other h t

“ hand, babies have dislikes for sour and bitter tastes r

e which could then protect them from poison b *Umami is considered to be a new taste bud, which is sensitive m Taste receptors regenerate every 2 weeks, but decline e to high protein foods- like chicken- notice how many people m naturally with age, especially for those who smoke and e

R think everything tastes like chicken* drink alcohol heavily, which is why these people prefer

) e extra seasonings on their food- they are losing their t s a sensation of taste over time. t (

n o i t a t s u G

” n o i t a t s u g s i d

Smell is a chemical sense, achieved through olfactory receptor cells throughout the nasal lining The olfactory receptor cells detect odors and send Smell information is directly sent, not relayed through, information to the olfactory bulb, which then the thalamus to areas of the brain including the limbic sends the information to the temporal lobe and system, which is why smell can quickly trigger memories, emotions, and thoughts

Submitted by Mike McLane, Sterling Heights High School, Michigan: Permission to use for face-to-face instruction with students only. Sensation and Perception n

o limbic system (remember the thalamus relays Unlike taste receptors, olfactory receptor cells do not i t c information for all senses except smell) regenerate, meaning that once damaged they are gone. a f l Over time, these cells naturally decline. O

Anosmia- refers to the inability to distinguish between

different smells

Sensory interaction- smell and taste interact to detect When you have a cold and your sense of smell is

information from the environment affected, you probably notice during this time that food

does not taste the same.

) l l e m S (

” l l e m s s e i r o t c a f d l o “ r e b m e m e R

Submitted by Mike McLane, Sterling Heights High School, Michigan: Permission to use for face-to-face instruction with students only. Sensation and Perception

Different types of skin receptors are activated through specific Majority of skin receptors are located on our hands and

types of stimulation- like pressure, warmth, and cold. face, which is why when we get a pimple on our lip it

However, there are no specific receptors for hot stimulations- hurts. The least amount of skin receptors are located on

the sensation of hot occurs when both the warmth and cold our back- a slap to the back is not as painful as a slap to

receptors are activated together the face

Frost bite can be described as burning because when we

)

y come inside we activate both warm (inside) and cold d

o (from outside) receptors, which results in the sensation B

( of hot s e Gate-control theory is used to explain the sensation of pain, The release of endorphins, a neurotransmitter that s n

e which states that the spinal cord contains a “gate” that either is blocks pain, helps to close the “gate”, which is why pain S

c open allowing pain signals to enter and continue to the brain, medication helps ease pain signals from reaching the i t

a or be closed blocking the pain from going to the brain brain m The release of substance P, a neurotransmitter that o S

reports pain, opens the “gate,” resulting in the sensation

of pain

Kinesthetic sense is a sensory system that monitors the When a person loses an arm or a leg due to an accident

position of individual body parts and movements and reports then that person would see a kinestologist, who would

this information to the thalamus and cerebellum try to match a prosthetic limb to the rest of the body

parts

Vestibular sense is a sensory system that monitors the head When people get dizzy, they put their hands over their

position and balance through receptors in the semicircular ears to regain balance

canals and the vestibular sacs located in the inner ear

Submitted by Mike McLane, Sterling Heights High School, Michigan: Permission to use for face-to-face instruction with students only. Sensation and Perception

n Perception is the process of organizing and interpreting Perception is opinion, We all use the same sensory o i t sensory information which is what accounts organs to detect stimulation p e for differences among from the environment, but we c r taste of foods, likes and all differ in our perceptions, e P

dislikes concerning which are influenced by

smells, sounds, etc. memories, personality, and

expectations.

Process of Top-down processing is based on your If somebody told you right before you were take a bite

Perception expectations and past experiences of a burger that it was disgusting then that person’s Perceptual set- is an example of top-down opinion would have an affect when you tasted that processing, which refers to our previous burger knowledge, or set of opinions about a particular object or topic Parallel distributed processing states that the You are able to smell while visualize at a object at the interpretation of a stimuli is based on several same time due to parallel distributed processing areas of the brain simultaneously working together Gestalt Gestalt psychologists studied how we perceive A bike assembled, or put together looks different than Psychology objects; emphasized that the whole is greater, the same bike broken into parts on the garage floor or different than, the sum of its parts Figure-ground relationship- we organize The reason hunters wear camouflage is that animals are information by separating the “figure” from the unable to separate the hunter (object- figure) from the “background” woods (background- ground) Grouping principles- our perception, or interpretation, depends on how we group objects Similarity- group similar items You would group all boys as one group of boys Proximity- group items that are close People standing near one another are perceived as one together group- “Hey, all of you standing over there” Closure- looking at the whole; tend to fill in If a circle was lit up by bulbs and a few bulbs were the gaps burned out, your brain would fill in the gaps Continuity- once an object starts moving If you watched a car drive off, you would believe that you perceive it as moving in same way the car continued in the same direction Depth perception is the ability to see in 3D

Submitted by Mike McLane, Sterling Heights High School, Michigan: Permission to use for face-to-face instruction with students only. Sensation and Perception

Depth Visual cliff demonstration- a laboratory Evolutionary psychologists believe that depth perception Perception device, which showed that babies would not was innate because it helped to protect babies from cross the clear glass placed between 2 danger- like falling. structures, proving that depth perception is innate Binocular depth cues- using 2 eyes Retinal disparity- slightly different When you look at object with one eye and then with perception of images are produced because both eyes, the object looks slightly different eyes are positioned on different parts of face Convergence occurs when the eye muscles You experience convergence if you were to bring an strain when an object comes too close object, like your finger, very close to your face

Monocular depth cues- using one eye Relative size- objects appear larger when Hold something close and then slowly pull it away from closer your face and the object will appear to become smaller- like a plane taking off Relative motion- objects move slower when When traveling in a car, the trees, which are further further away away, appear to be moving slower compared to sign posts that are closer to the car Relative height- distant objects appear Mountains in the distance appear to be on top of lake, higher in visual field than closer objects which you are standing in right in front of Linear perspective- parallel lines seem to If you were to look down a set of railroad tracks in the come together, or merge in the distance distance the tracks would appear to be coming together Texture gradient- when an object is close From a distance, people or objects appear different- it is you would be able to detect fine details; not until they are up close that we can detect or notice however, when an object is far away, you little details are not able to detect the details of that object. Perceptual Perceptual constancies refers to perceiving an object as not changing, or remaining constant even Constancy though different images are presented to the retina when the size, shape, or lightness changes or moves

Submitted by Mike McLane, Sterling Heights High School, Michigan: Permission to use for face-to-face instruction with students only. Sensation and Perception

Size constancy A door that swings open and closed appears to change in size. When the door opens it appears to become slower and larger when the door closes. Size constancy refers to the understanding that regardless of the different images that are produced by it opening and closing, it is still the same door Shape constancy A bottle that is turned side ways is going to present a different shape, but most people understand that it is still the same bottle Lightness When you wear a yellow sweater outside it will appear brighter than if you wore constancy the same sweater inside. Even though it looks different you know it is still the same sweater Phi Sometimes a restaurant will have a blinking sign out front that appears to have phenomenon- an arrow pointing towards their parking lot. This sign, which appears to show refers to how the direction, is the result of light blinking on at a certain speed. When the lights movement of start off slow and then speed up it shows a direction as the lights are turned on. fixed lights when Think about dominos- as the dominos fall they fall in a certain direction, which presented, or the shows the path that they will fall. turned on and off could indicate direction, or meaning

Submitted by Mike McLane, Sterling Heights High School, Michigan: Permission to use for face-to-face instruction with students only.