CH5 Flashcards
sensation
perception
what we have to create meaning (like building blocks)
combination of sensations pkus prior knowledge to interepret sensations and make meaning
transduction
place where sensations are translated to elctrochemical signals
bottom up processing
neural processinga t sensory organs.
senses–> brain
info from environemnt
top down processing
- individually unique from expeirinces
- combinig info with prior understanding of the world to create perceptin
gestalt psychologis
20th century
belived were born with predisposed ways of organziing infomation so its useful
interested in bottom up provessing
gestalt priciples of organization
1 figure grabd
2 principle of proximity
3 similiarty
4 closure
5 good coninuation
6 common fate
anatomy of eye (be able to label it)
nearsighted vs far sighted
the retina
- rods and cones
- cones: fovea
- rods: images, sense movemrnt and location around retina
- dark adaptation: how you adapt to less light, as R and C adaptbi
bipolar and ganglion cells
bipolar
- interpet info by connections to several rods or one cone
- 1:1 for cone to bipolar cell ration
- into sent to ganglion cells
- infro from multiple rods sent to large ganglion (M cell)
info from one cone sent to small ganglion (P cell)
ganglion
- sees bits and pieces
- eventually the bundle of neurons makes the optic nerve
- organization allows for detetcion of edges
receptive fields
visual pathway to cortex (EXPLAIN diagram)
- both eyes see left and right visual fields
- primary VC or striate cortex
- light hits C and R (back of retina)–> biploar cells–> ganglion cells–>VC (occipital lobe) –> temporal lobe (ventral stream–what is it?) or parietal lobe (dorsal stream–where is it?) and to limbic system (how do you feel when you see object)
retinotopic organization and
-spatial organization of retinal images maintained through visual pathway
feature detectors, (complex and simple cells)
-special neurons that respond to speicifc stimuli in brain to detect edges, lines, angles, and movement.
- allow to see lines at diff angles in environemt (IN BRAIN)
-Hubel and Wisel (1960) nobel prize
-simple cells: lines at diff angles
- complex cells: respind to verticle lines in motion
two theories of colour
trichromatic
- comparing the activation of the different cones
- For example, when you see a blue car, it is because the car is reflecting short wavelengths to your eye, which activate the S-cones but not the M- or L-cones.
opponent process theory
- cells in visual pathway increase activation when recive info from one kind of come and decrease when they see a second colour
- colours are paired with complementary colours
- explains after images
- looking at one color for a long period causes those receptor cells to become fatigued. When they begin sending weaker signals, their opposing cells fire, sending signals that cause the perception of the opposing color.
three types of cones
- S cones: short light waves perceived by cones as blue
- M cones: medium wavelength periceved as green
-L cones: long wavelengths red/orange
recpetive fields
- ganglion cells have recpetive fileds
- help interpt where edges of images are
- center on vs center off cells
- when whole field illuminated, firing is sae
allsows for single cell to send variety of info about surface of object
monocular depth cues
- occlusion
- relative height
- perspective convergence
- familar size
- atmospheric perspectvies
- relative size
the ames room
- 1930
depds on assumption of relative hieght
room seems square isnt - cieling is not same height
bionolcular depth cues
- input from both eyes
- retinal dispartity: brain maeks comaprions between both eyes
- convergence: eyes move to focus on close objects, (movemnt intereped by brain)
Binocular cues create a three-dimensional image of the world one views. There are two types of binocular depth cues: convergence and retinal disparity.
sound
frequency: rate of vibrations
- pitch (high/low)
- meausred in cycles per second (hertz)
intensity (amplitude)
- loudness
- db (pressure meausre >100db human earto much
anatomy of ear (in order of how it travels)
- pinna
- tympanic membrane
- ossicles
- oval window
- cochlea
- basilar membrane (in cholea)
- to brain
cochlea
- transduction happens here
- fluid filled
-basilar membrane (sound waves cause membrane to move up and down-bends cilia on hair cells attahced ot membrain, brain recived excitatory message)
two theories of sound
place theory
- high pitch near oval window, low picth at far end
- cochlea has diff thickness as diff places
- location of firing on basil membrane helps us periceive pitch
20-2000 hz is natural range
frequencey throry
- more rapid firing = higher pitch
- neurons fire in sucession, spaced out = increase mesage
auditory pathway
basic pathway
- ear, brainstem, thalamus (MGN), temporal lobe,
0 simple sounds processed down, complex sounds processed in cortex
auditory cortex, tonotopic organization
- in temporal lobe
-tonotopic: of basicalr membrane: special organziestion of membrane maintined through auditory pathway
sound localization
- we can percive where sound is coming from becasue ears are on outer side of head
- brain computes location.
Binaural cues
comparisions between info from the two ears to understand object location
music
linked to mood
stress hormone
involunary musical imagery (annoying song gets stuck in youre head)
human speech
- the mcGurk effect (ba pa fa) visual info supplemnts for sound
smell and taste and chemical messages
- chemicals are called: odurants and tasteants
-chemorecpetors: specialized cells that respond to odurants and tastenats
animals with better smell
- afriacn rats and TB diagnosis
smell (olfaction)/ how do we smell
-not through thalamus
-plays role in mate
- humans not to good at this
- bette rin dogs
olfactpory mucosa
- location of respector cells of nose
olfactory receptor noron (ORN)
-over 350 kinds
allow for perception of trillion differnt odouarants
- odours made of many odourt molecules
- recepts send emssage to olfactory bulb
-difficult to study
- smell depends on expectations (garlic vs sweat pizza)
taste
- correlation between molecular properties of stimuli of stimuli and effect on body (high calroie foods are sweet0
1.sweet
2.sour
3.bitter
4,salty
5.umami (savoury)
how we taste on the tongue
- papillae = bumps on tongue. taste buds are in these bumps
- fungiform (fungus looking-side)
2.foliate (look folded-back)
2.circumvallate (small mound-back)
4.filiform (all over tongue, no tastebuds- more for texture)
taste bud
-50-100 sensitve cells in each taste bud (=1 taste pore)
-transduction happens when chemicals bind to receptor site on taste pore
-neural message sent
taste + smell = flavour
-in the brain its processed
- smell signals –> temporal lobe
- taste signals –> region betweeen frontal and temporal lobe
-orbitofrontal cortex combines info here. also visualinfo and bimodal neurons that detect taset and smell
skin mechanorecptro
-mechanorecptor
- cells that repsond to rpesseure
-merkel
meisner
ruffini
pacinian
somatosensor cortex
messages traves to SC parietal lobe
- diff types of messages combines here
-somatotopic organization: two adjancent points on skin = adjacent on cortex
-expectation is important. increased brain actvity when sense expected
temperature
seperate hot and cold thermoreceptors
-relativepain
pain
-response to damage
-skin receptors nociceptors
-protetcs us
- people who live without
gate controlled theory of pain
-melzack and wall
-0 pain can be vlocked in spinal cord by signals from brain
-painful foot marathon can be overcome
three cell types
1. pain fibres (s fibers)
2. a transmission cell (T cells)
3. fibres yhat send messages about non painful stimuli (L fibres. block T cells)
kinestethic sense
-understanding location of our body in space
- how to move body
- receptors in joints and muscles
-info sent to somatsenseoty cortex
vestibular sense
- semicircular canals (above cochelea
- senses changes in acceleration
- roattion of head
conatin hair cells respond to gravity
2.vesticular sacs (inner ear)
- respond to balance
-posture
stimulus detection
-level of intensity required to create a concious expeirnce (varys from personn to person and not absolute)
absolute threshold
- as intensity incresases, the point where you will see the stimulus (like light)
-some say there is stimulus when there is not, some say
Hit : correctly detecting the presence of a stimulus.
Miss : failing to detect the presence of a stimulus.
False alarm : incorrectly reporting the presence of a stimulus when it is absent. Correct rejection : correctly reporting the absence of a stimulus.
differnece threshold
- smallest abount of stimulus needed for a differnece in agnitude to be detcted
-how many pounds added to weights before you sense a difference
-easily notice small changes in two less intense stimuli
-the more intense the simulus, the longer required change to notice differnce
webers law
- ability to notice diff ebtween two stimuli is a constacnt proportion to intensity or size of stimulus
- increase stimulus = increase requreid change to notice a diff
