Psych Midterm 2

sensation

allow to pick up signals from the environment

perception

turn signals into something meaningful

important part of sensation and perception

light

not all sensations and perceptions are _

accurate

Naïve Realism

belief that our sensory systems are

infallible and that our perceptions are perfect

representations of the world around us 

infalluble

incapable of mistakes or being wrong

5 sensations

1. Vision

2. Hearing

3. Smell

4. Taste

5. Somatosensory

sensation most prone to naive realism

vision

all sensations rely on

transduction

Transduction

process of converting an external energy

or substance into electrical activity within neurons

transduction occurs via

sensory receptors

Sensory receptor

specialized cell responsible for converting

external stimuli into neural activity for a specific

sensory system

all sensory receptors are prone to

sensory adaptations

Sensory Adaptation

activation is greatest

when a stimulus is first detected

sensory adaptation Response to the stimulus _ in strength over

time

declines

how is sensory adaptations different from hibituation

SA = physiological adaptations

H = psychological adaptations

9 parts of vision

Cornea

Vitreous humor

Pupil

Fovea

Lens

Blind spot

Ciliary muscles

Retina

Aqueous humor

most complex and developed sense

vision

Cornea definition

transparent

cover for the pupil, lens,

and iris

cornea function

shape bends incoming

light to focus the image at

the back of the eye

Pupil definition

circular hole

through which light enters

the eye

Pupillary reflex

muscle response that dilates or contracts the pupil

pupillary reflex occurs _

simultaneously regardless if only one eye is triggered

when does your pupil dilate

when trying to process complex information or when we find someone attractive

when does our pupil contract

when bright light enters eye or when an object is approaching the eye

Lens definition

changes curvature to

keep images in focus

lens Consists of some of the

most

unusual cells in the

body

Presbyopia

declining

eyesight with age due to

the lens becoming more

rigid over time

completely transparent allows

light to completely passs through

Ciliary Muscles definition

 changes the

thickness of the lens

ciliary muscles are a ring of

 smooth muscle fibers

ciliary muscles connected to the lens via

sensory ligaments

ciliary muscles allows

the lens to focus on

objects depending on their

distance

ciliary muscles are linked to

near sighted and far sightedness

Nearsightedness is also known as

myopia

Nearsightedness

inability to see

far objects well but able to

see close objects clearly

nearsightedness results when

images are

focused in front of the rear

of the eye, due to our

cornea being too long

Farsightedness is also known as

hyperopia

Farsightedness

inability to

see close objects well but

able to see far objects

clearly

farsightedness results when

cornea

is too flat or our eyes are

too short

humor is latin for

moisture

Aqueous Humor

 transparent,

gelatinous fluid supporting

the structure of the cornea

and lens

Vitreous Humor

transparent,

gelatinous fluid supporting

the primary structure of the

eye and retina

Fovea

entral portion

of the retina

fovea is responsible for

acuity

acuity

sharpness of vision

Blind Spot

point of exit of

ganglion cell axons where

the optic nerve connects to

the retina

blind spot contains

no rods or cones

blind spot creates

some of the most

remarkable visual illusions

what does the brain do in blind spots

tries to fill in or guess the missing information

Retina

membrane at

the back of the eye

responsible for converting

light into neural activity

retina contains

photoreceptors

Photoreceptors

cells that respond to light

photoreceptors are not

equally distributed across the retina

two types of photoreceptors

rods and cones

location of rods

more densly populated on peripheral of retina

location of cones

in center of eye

Rods

sensitive to light

shape of rods

Long and narrow

rods enable us to see

basic shapes and forms

Dark adaptation

time in dark before rods regain

maximum light sensitivity

example of dark adaptation

in dark room and over time you can see more and more

rods contain

photopigments called rhodopsin

approx how many rods in the retina

125 million

night blindness

inefficient rods inhibiting to see light in dark

Cones

sensitive to detail

shape of cones

cone shaped

cones enable us to see

colour

cones are less sensitive to

light

cones contain

photopigments called iodopsin

approx how many cones in the retina

6.4 million

insufficient idopsin results in

colour blindness

Colour Blindness

inability to see some or all colours

colour blindness Most often due to

absence or reduced cones due to

genetic abnormalities

colour blindness can also result due to

brain injury

Colour Blindness more common in _ and why

men because they only have 1 X

what chromosome has the gene for colourblindness

X and it is always expressed

how many shades can normal vision see compared to colour blind

normal: 1 million

colour blind: 5-10%

Blindness

dramatic reduction or inability to see

blindness vision

 ≤ 20/200 on Snellen eye chart

blindness Can be the result of 3

cataracts, clouding of the lens, or

glaucoma

blindness To compensate, they often rely on

other senses

blind invidividuals will create a whole new sense

echolocation

Ben: tough himself to see. Able to ride a bike, basketball and doesnt not consider himself blind

Visual Agnosia

a condition in which a person can see (usually colours) but

cannot recognize or interpret visual information

Visual Agnosia caused by a

disorder in the parietal lobes

what is less common than blindness and colour blindness

visual agnosia

depending on what is damaged in the pariental lobe

can see shapes and not faces or visa versa

 Sound

vibration (waves)

Sound waves can travel through 3

gases, liquids, and

solids

we hear sounds best when they travel through

air

3 Elements of Sound

1.Frequency

2.Amplitude

3.Timbre

Frequency also called

pitch

Frequency

number of cycles a sound wave completes

in a given time

frequency is measured in

hertz (Hz)

Humans hear sounds between

3—20,000 Hz

low frequency 2

long wavelength

less sound waves

high frequency 2

short wavelengths

more sound waves

Amplitude is also called

loudness

Amplitude

strength (or height) of a sound wave

amplitude Measured in

decibels (dB)