The way by which the brain organizes and interprets sensory information into meaningful experiences and representations of our external world

the weakest amount of a stimulus that a person can reliably detect 50 percent of the time. This includes vision, hearing, smell, taste, and touch.

The principle that for any change in a stimulus to be detected, a constant proportion of that stimulus must be added or subtracted. The larger or stronger the stimulus, the larger the change required for a person to notice the difference.

EX: 3 lbs. – 6 lbs. = easily noticed

100 lbs. – 103 lbs. = hardly noticed

the minimal difference between two stimuli that people can reliably detect.

AKA – Just Noticeable Difference

belief that the detection of a stimulus depends on factors involving the intensity of the stimulus, the level of background stimulation, and the biological and psychological characteristics of the perceiver.

EX: more likely to notice every little noise while walking alone in the dark as opposed to, while walking in the daylight.

Senses are most responsive to increases and decreases, and to new events rather than to ongoing, unchanging stimuli.

EX: Eyes adjust to a dark bedroom after a few minutes. Adaptation occurs for the other senses as well

sensitive to lower levels of light and are the basis for night vision (peripheral vision)

i. Allows us to see in black and white

ii. We have between 75 – 150 million rods

require more light than rods and work best in daylight

i. Allows us to see in color

ii. We have between 6-7 million cones

A transparent covering on the eye’s surface through which light enters

the opening in the iris that regulates the amount of light entering the eye

i. The iris (the colored part of the eye) increases or decreases the size of the pupil reflexively

a flexible, transparent structure in the eye that changes its shape to focus light on the retina

i. Through accommodation the lens changes its shape to focus images more clearly on the retina

the innermost coating of the back of the eye containing the light-sensitive photoreceptor cells

area near the center of the retina that contains only cones and responsible for giving rise to the sharpest vision

a binocular cue for distance based on the slight differences in the visual impressions formed in both eyes.

The closer an object, the greater the retinal disparity (hold finger an inch and then arms length away and alternate looking at it with only one eye…do you see a difference?).

a. ______________ = the nerve that carries neural impulses generated by light stimulation from the retina to the brain

b. Contains millions of ganglion axons that transmit visual information to the brain

c. Information is routed to the thalamus and from there to the visual cortex in the occipital lobe

The visual processing area of the brain. It is associated with visuospatial processing, distance and depth perception, color determination, object and face recognition, and memory formation.

People who have no color vision and can see only in black and white

Born with only 1 type of cone

a. People who can see some colors but not others

High frequency =

Low frequency =

Frequency is

Amplitude is

Great Amplitude =

Small Amplitude =

a sheet of connective tissue separating the outer ear from the middle ear that vibrates in response to auditory stimuli and transmits sound waves to the middle ear.

three tiny bones in the middle ear (hammer, anvil, and stirrup) that vibrate in response to vibrations of the ear drum.

the membrane-covered opening that separates the middle ear to the cochlea.

hearing.

the snail-shaped organ in the inner ear that contains sensory receptors for hearing.

membrane in the cochlea attached to the organ of Corti.

a gelatinous structure in the cochlea containing the hair cells that serve as auditory receptors.

auditory receptors that transform vibrations into neural impulses

nerve that carries neural impulses fro the ear to the brain

Auditory messages are processed in the auditory cortex in the temporal lobe of the brain

The belief that pitch depends on the place along the basilar membrane that vibrates the most in response to a particular auditory stimulus.

Neurons line up on the basilar membrane standing ready to respond by producing sounds of different pitch when they are “struck”

Analogy = Think keys being struck on a piano

dbest explains pitch of high-frequency (high-pitched) sounds.

Cannot account for frequencies 1,000 hertz and below

a. Groups of neurons respond to 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.

b. Neurons fire in alternating succession

Analogy = Think old methods of warfare (one group stands and fires while the other group kneels and reloads)

a. Individual nerves can only fire at a range of 1,000 times per second and in combination, only up to 5,000 times.

This theory, extended by the volley principle, best explains pitch perception for low-frequency (low-pitched) sounds

a. Prolonged exposure to noise of 85 decibels can cause this as can brief exposure to 120 decibels

a. form of deafness, usually involving damage to the middle ear, in which there is a loss of conduction of sound vibrations through the ear

b. Ear drum punctured, 3 bones lose ability to vibrate

c. The use of a hearing aid is beneficial

deafness associated with nerve damage, usually involving damage to the hair cells or to the auditory nerve

Auditory messages are processed in the auditory cortex in the __________ of the brain

Smell and taste are known as the ___________ because they are sensitive to chemical molecules.

a. Smell is the ONLY sense that _____ routed through the thalamus

Select the 5 basic tastes

a. ______ _______ regenerate quickly

b. 7-10 days

c. When you “burn” your tongue, you are actually destroying your ______ _______

A body sense that keeps us informed about the movement of parts of the body and its position in relation to one another.

a. a mode of perceptual processing by which the brain recognizes meaningful patterns by piecing together bits and pieces of sensory information.

b. Starts with no preconceived ideas…the stimulus influences your perception. It’s data driven.

a. a mode of perceptual processing by which the brain identifies patterns as meaningful wholes rather than as piecemeal constructions.

b. Ex: Recognizing faces of people we know – we don’t need to look at each individual part/feature of their face individually.

c. It uses context clues, past experience, expectations, and prior knowledge to come to an analysis.

GESTALT PRINCIPLES

when we see a number of similar objects, we tend to perceive them as groups or sets of those that are close to each other.

GESTALT PRINCIPLES

when we see a number of similar objects, we tend to perceive them as groups or sets of those that are close to each other.

GESTALT PRINCIPLES

when similar and dissimilar objects are mingled, we see the similar objects as groups.

GESTALT PRINCIPLES

when we see a familiar pattern or shape with some missing parts, we fill in the gaps

GESTALT PRINCIPLES

the principle that objects positioned together or moving together will be perceived as belonging to the same group.

GESTALT PRINCIPLES

we tend to see continuous patterns, not disrupted ones.

a. cues for depth perception that involve both eyes.

b. Our eyes are a few inches apart, so each eye receives slightly different images of the world.

a. cues for depth that can be perceived by each eye alone.

a. (Young-Helmholtz Theory)

b. The retina has 3 types of color receptors

i. Red – Green – Blue

c. The response of these cones allows us to see different color

d. When these are stimulated in combination, we can produce any color

i. Example = mixing paint

a. Suggests that the experience of color results from opposing processes involving 2 sets of color receptors.

i. Red-green receptors

ii. Blue-yellow receptors

iii. Black-white receptors (not color but brightness)

b. When one of these receptors is activated the other is blocked

i. Example When the red is activated, the green is blocked, so we see red

a. Developed by Ronald Melzack & Patrick Wall to explain how we control pain

b. A “gating” mechanism (a pattern of nervous system activity) in the spinal cord opens and closes to let pain messages through to the brain or block them out

c. We can lessen pain by 1) shifting our attention away from the pain impulses or 2) by sending signals to compete with the pain

d. Example = Rubbing your “funny bone” after you have hit it helps to reduce the pain

a. monitors the position and movement of the body and maintains balance.

b. This is why you feel dizzy when you get an ear infection – it is disrupting the fluid in the canals in the ear.

a. The ______ bulb routes the information directly to the ________ cortex of the temporal lobe and the limbic system

b. The connection between the _________ system and the limbic system may explain the relationship between odors and emotional memories.

a. the tendency to perceive an object as having the same shape despite differences in the images it casts on the retina as the viewer’s perspective changes.

b. EX: Perceiving a round bowl on the counter

Cue for distance based on the degree of muscular tension required to focus both eyes on the same spot.

The closer the object, the greater the tension

DEPTH CUES

when two objects are believed to be the same size, the one that appears larger is perceived to be closer.

DEPTH CUES

When objects block or obscure our view of other objects, we perceive the obscured object as farther away.

DEPTH CUES

Smog, dust, smoke, and water droplets in the atmosphere create a “haze” that makes distant objects appear more blurry than nearer objects.

DEPTH CUES

closer objects appear to have a coarser and more detailed texture than more distant objects.

DEPTH CUES

perception of parallel lines converging as they recede into the distance.

DEPTH CUES

patters of light and dark, or shadowing, create the appearance of three-dimensional objects or curving surfaces.

an optical illusion where two lines of the same length appear to be of different lengths

a. – a type of movement based on the rapid succession of still images, as in motion pictures.

b. AKA – the phi phenomenon

Hearing Loss/Deafness how many people affected?