Module 5 Flashcards
What is sensation?
the detection and representation of info through sensory receptors (bottom-up)
What is perception?
organization and interpretation of info in the brain (top-down)
How does the eye analyze vision?
-transforms light energy to electrical energy
Go over eye diagram
have fun
Where + what does the iris do?
coloured muscle that controls the diameter of the pupil
Where and what does the pupil do?
hole in the iris to allow light through
Where and what does the lens do?
accommodation - bends light to focus on the retina
Where and what do the ciliary muscles do?
contract to change the lens shape
Where and what does the retina do?
contains photoreceptors to transduce light to neural impulses
Where and what does the optic nerve do?
transmits signals to the visual cortex of the brain
Where and what does the optic disc do?
axons of retinal ganglion cells becomes a blind spot
How does the retina perceive light?
- 3 steps
- light enters and triggers a photochemical reaction in the rods and cones
- chemical reaction activates the bipolar cells
- activate ganglion cells, to the optic nerve, to the visual cortex
2 photoreceptors
=name
-how many?
-field of vision
-type of vision
-light
-level of acuity
=cones
-6 million
-central (fovea)
-colour
-bright light
-good acuity (direct line to optic nerve)
=rods
-125 million
-peripheral (periphery)
-black and white
-dim light
-poor acuity (shared line to optic nerve)
How are cones and colour vision related?
humans need all 3 types of cones to have full colour vision
What is the trichromatic colour theory?
-red (L), green (M), and blue (S) cones
-activation of the combination allows us to see all colours
What is the opponent process theory of vision?
3 opponent processes in the retina and thalamus
-red/green, blue/yellow, white/black
-some turned on and some turned off to create colours
Review the visual pathway diagram
have fun
What is the LGN in the visual pathway?
-the lateral geniculate nucleus
-where the thalamus connects with the optic nerve
Which part of the brain fires when a face is shown?
FFA - fusiform face area
Which part of the brain fires when it is supposed to process moving faces?
occipital face area
What do the amplitude and frequency of hearing mean?
amplitude = loudness
frequency = pitch
review hearing diagram
have fun
How does hearing work?
sounds waves enter and cause vibrations which are transformed into neural signals
Where are the smallest bones in the body located?
the ear
(mallus, incus, stapes)
What is the pathway of hearing?
-9 steps
1) sound
2) vibrate tympanic membrane
3) vibrates ossicles
4) vibrates oval window
5) vibrates the fluid in the cochlea
6) bend hair cells on the basilar membrane
7) transmit impulses to the cochlear nerve
8) thalamus
9) auditory cortex
How does the ear perceive loud sounds?
more hair cells are activated
How is the change in the pitch perceived by the ear?
-beginning of the membrane = high
-end of the membrane = low
Sound localization (3 types)
=type
-info
=pinna cues
-the shape of the outer ear
-not very good at localizing sound
=timing
-the difference in the time of arrival gives a cue to the localization
=intensity
-sound slightly less loud with one ear than the other gives a cue to the localization
Where is it easier to localize sound?
directly infornt
What are the 2 different ways to lose hearing?
=type
-info
=sensorineural
-loud noises
-continuous noise
-hair cells -> auditory nerve -> cortex)
=conductive
-age
-ear infection
-ruptured ear drum
-wax build up
How do hearing aids work?
cochlear implants
-microphone/amplifier/ speaker increase volume to inner ear
What kind of sense is taste?
-chemical sense
-reproduce every 7-14 days
What does taste sensitivity do?
-nutrition
-toxin avoidance
Taste nerve pathway
Hypothalamus (hunger)
Amygdala (emotions)
Hippocampus (memory)
Frontal cortex (conscious perception)
What kind of control is taste?
top-down control
Review nose anatomy
have fun
What kind of sense is smell?
-chemical sense
-mucus dissolves particles
How do smell and taste interact?
the airflow through the nose is necessary for full and proper taste
What are gestaltists?
-who?
-when?
-the theory that we organize pieces of information into a whole, that complete percept is larger than its building blocks
-we organize pieces of info into wholes
-german psychologists
-1920s-1930s
2 ways to form a perception
-figure and ground
-grouping
What are the 5 different types of grouping to form a perception?
-proximity
-similarity
-continuity
-connectedness
-closure
What are figure and ground, and how does it work?
Ability to discriminate the figure from its background
-words in the book vs paper
-automatic
-perception can change depending on the stimulus
What is proximity and how does it work?
group nearby figures together
-spacing influences catagorization
What is “similarity” and how does it work?
group similar figures together
-like objects are often categorized together
What is continuity and how does it work?
perceive connected patterns rather than disconnected ones
-single continuous lines instead of short cut ones
What is connectedness and how does it work?
objects that are uniform and connected are seen as a unit
-same shape + same size = single unit
What is closure and how does it work?
fill in the gaps to create a whole image
-even with no outlines the brain will see the familiar shape
How is object recognition influenced?
(3 ways + definition)
1) expectations
-words said = brain wants to see
2) focus of attention
-switch focus = no notice change
3)compilation of bottom-up and top-down processes
-due to pre-knowledge and association of environment can differentiate objects
What is motion perception?
-can build a perception of motion from quickly flashing scenes
ex; cartoons, phi phenomenon
What are the 2 types of depth perception?
=binocular cues
-convergence
-crosseyed
-close eye and object moves
=monocular cues
-accommodation
-lens out when close
-lens in when far
What is motion parallax?
close objects move faster than far ones
close = blur
far = slow
What are the 5 pictorial perceptions?
=name
-info
=interposition
-object block other = closer
=relative size
-big = close
=linear perspective
-big parallel line = closer for converging at a single point
=texture
-more texture = closer
=shading
-top light = convex
-bottom light = concave
What is a perceptual organization that is beyond vision?
=language
-foreign language sounds faster + harder to space/decipher
-no top-down knowledge to perceive the info
the 4 senses of touch + where they are located
=Merkel’s receptors
-close to the surface, fire continuously if the object touch
=Meissner’s corpuscles
-close to the surface, fire when pressure applied + removed
=Pacinian corpuscles
-deep response to vibration and texture
=Raffini’s cylinder
-deep response to stretch
There are over ___ types of olfactory receptors.
350
How does gate-control theory suggest pain is blocked?
the brain activates L-fibers to block pain signals
Absolute threshold is determined by the correct identification of a stimulus ___% of the time
50
Which 2 systems use the bending of cilia to send messages to the brain?
-auditory
-vestibular
What does binaural recording do? (2)
-interaural time differences to create an illusion
-create a salient (noticeable) perception of an auditory soundscape
What is Weber’s Law?
-notice the difference between two stimuli is directly proportional to their size/intensity
=small easy, large is not as easy
