▪ test 2

What is the smallest stimulus that you can detect?

▪ sensation

▪ absolute thereshold- smallest stimulus that you can detect

▪ difference threshold-the smallest amount by which two sensory stimuli can  differ in order for an individual to perceive them as different.-weber ▪ weber- the size of a just nautical difference is a constant fraction of the stimulus  to which it is compared

▪ intensity of stimulus over the amount that must be added to the intensity gives  the constant referred to or webber’s fraction

▪ fechner- the strength of the stimulus grows with the logarithmic stimulus intensity  s equals something

▪ Muller specific nerve energies- dome differences in sensory quality ( green v. red) ▪ can’t have that many sensory nerve structures

How thresholds are important?

Don't forget about the age old question of What do phonemes mean?

▪ pattern theory- pattern of excitation  

▪ detection outcomes- sometimes we sense some things and sometimes we don’t ▪ hit- when we sense the target

▪ false alarm- i detect something no sensation

▪ correct negative- don’t sense it but there is one

▪ miss- detect it but miss it

▪ if your hit rate goes up and false rate stays the same you get better at sensations  and your sensitivity increases

▪ payoff matrix- benefits or costs from responses

⁃ radiology- is it better if he looks at X-ray and says he thinks there’s cancer  and there isn’t any- overly cautious  

⁃ jury example- put innocent person in jail or not  

▪ how thresholds are important here

What is parvo cells?

Don't forget about the age old question of What is the largest empire in the world?

▪ light travels in waves  

▪ waves are measured in aplitude- height determine brightness ▪ wavelength- distance- color hugh

▪ human eye- rods and cones detect colors- optic nerve caries to brain- retina gets  vision

▪ rods and cones- duplex- work hand in hand- rods help with achromatic vision low light no color

▪ cones- color high light levels day vision good acuity

▪ lateral inhibition- the way neurons work and create inhibition in adjacent  neuron- response always sideways- mediate adjacent cell is fired ▪ important we see the edges as being brighter and darker in black blocks ▪ in the light column they receive plus 3 light- each gives a minus one to the  adjacent one because they inhibit- it makes minus 2 Don't forget about the age old question of What are the forms of public speaking described by aristotle?

▪ plus 3 minus 2 is plus 1

⁃ as bright as plus one unit

▪ ganglion cells report visual receptors

▪ outside of zone light they won’t be activated

▪ lateral inhibition plus minus thing is integration effect

▪ color receptors- cones contain pigments sensitive to different wave ▪ short blu

▪ medium green  

▪ long red

▪ pigments support idea of three chomatic color vision

▪ our color vision comes from all different cones

▪ feature detectors

▪ all have a preferred target

▪ some sensitive to motion

▪ some to parallel lines

▪ if we use our process of seeing our visual perception- explain visual  phenomenan  We also discuss several other topics like What theory explains drivers of human behavior?

▪ light detectors and face detectors- evenly balanced out and against each other ⁃ in our conscious only one feature detector claims what it sees ⁃ get habituated to it and get into our conscious and then its always forward  in our conscious If you want to learn more check out When did the archean era begin and end?

▪ visuals aren’t perfect and we have different ways of seeing it ▪ necker cube doesn’t have depth cubes- we will focus on different locations  depending on how we want to see it- focus on different sections above or below  and that changes our view We also discuss several other topics like What are the steps in transcription in prokaryotes?

▪ gestalt laws- similarity group dots as blue and red because we organize them  in lines vertical not horizontal

▪ proximity law see three groups of dots because we want to link dots that are  together

▪ see green block as continuous even though it’s blocked- good continuation law ▪ closure law- we see a bias and a closed triangle even though it’s not complete ▪ simplicity- see as simple as possible don’t see weird shape we want to see two  rectangles on top of each other

▪ subjective contours- completion phenomenon- they’re implied in a  fragmented form and our brain sees them as 2 triangles on- see one as lighter to  amplify figure in the foreground

▪ binocular cues- 2 eyes- retinal image in each eye is different- eyes close to me  seen in different depths when close each eye- binocular disparity- rely on it to  understand depth

▪ when you much at the first figure we relate diagonal lines then two rats kissing  relate top two- principle of maximum likelihood- law of continuation- in the  visual system

▪ monocular cues- pictorial cues- can be represented on a flat surface creating  a 3D scene- pictoral cue gives that sense

▪ interposition- objects farther away blocked by objects in front blue is farther  than red block- monocular clues- don’t know it but position gives cue ▪ linear perspective artists use- parallel lines converge as they get farther away ▪ motion parallax- look out window when driving the car theres grass and river it  seems to be moving faster than river because objects closer to us are going in

the opposite direction even though they stay in the same place

▪ texture gradient- amount of texture gives us perceptional cues ▪ light and shadow sensitive to it- shadows show conceived and convexed  because light usually comes from above  

▪ apparent movement

▪ lamps and light don’t move when they’re lit in order

▪ first we light left then we light right

▪ in our perception experience we see as if it’s done quickly it looks like movement ▪ light travels light then left as long as not perceived as moving slowly ▪ induced motion

▪ different than apparent motion- if there’s an object and near by objects are  moving differently- the non moving object is seen as moving

▪ clouds and the moon- clouds are moving- moon can look like it’s moving ▪ cocktail party effect- if you’re in a party while there are so many sounds at a  party you can focus on the convo you’re having- pay attention to speech- can  hear if someone calls my name- selectively attend to stimuli at the moment ▪ broadbent experiment- participants listen to 2 stories one about river and one  about money in a bank- one ear hear story and one ear hear something else can’t explain stories because they can’t pay attention to both stories- when asked  about throwing stones at the bank- river bank or money bank- response changed  by what story they listened to- not consciously listening to story but it activates  attention

▪ attention- impossible figures- at first you don’t understand they’re impossible- 2  feature detectiors to understand- mango cells focus on big picture- broad  band feature don’t see problems

▪ parvo cells- narrow band and see problems in the figures

▪ to understand them we need to search the whole figure for broad band feature  detectors

▪ then we use narrow band to see the problems and incongruities ▪ big to small

▪ participants asked to look only at white shirted players- girl comes up they are  asked if they see the girl but they’re focus on white shirted people and they don’t  see girl- attention influences visual perception

▪ bottom up- source to brain visual perception- look at basic stimuli and process it  later

▪ top down processing we use previous knowledge and ideas to process stimuli  ▪ both important

▪ pandemonium model- have letter T according to bottom up the features are  shapes- similar features to letter t are r and p- the hardwired feature detectors  influence how we see it  

⁃ gives us opportunity we can use other ways to process visual stimuli  ⁃ can be primed with top down processing

⁃ if you expect something as T letter related you see it as t not just lines ⁃ bottom up see shapes

▪ context effects- ambiguous picture and how we are primed says how we will  see image- woman vs. old lady- young actress primed you see young woman ▪ pathway from visual cortex to the temporal lobe- visual agnosia lets you see  apple but not identify it

▪ visual cortex to parietal lobe- locating objects

▪ where parietal

▪ what temporal

▪ perceptual constency

▪ shape constancy and size constancy- dog isn’t bigger but we can take into  account our distance to object- dogs relative size to other objects in the  environment

▪ other visual stimulus takes into account scene changes and different things although you see different things we take into account our motions we don’t think  things grow

▪ open door- see something but I know it’s a door it didn’t just disappear ▪ habituation- simplest form of learning getting familiar to stimuli- responsiveness  to something new

▪ evolutionarily it’s important

▪ novel stimuli are always risky and once we’re habituated we know it’s safe and it  doesn’t provide any new info- need habituation to listen for new stimuli ▪ classical conditioning- pavlov is the father

▪ UR- unconditioned response reflex when dog sees food it drools ▪ Unconditional stimulus- food dog sees

▪ Conditioned response food with bell food is response

▪ Conditioned stimulus paired with bell

▪ once ^ relationship is established bring in second order conditioning- prepare bell  with light- when the dog sees it

▪ they all are linked

▪ generalization the tendency for stimuli to be similar in learning  ▪ little albert loves rats then he’s shocked with rats and afraid of rats ▪ he then fears rabbits because they look the same

▪ descrimination- respond differently to red light  

▪ we tense up with red light

▪ orange light is similar so the horn should come

▪ but with conditioning orange doesn’t have horn so don’t tense up ▪ extinction- weakening of learned stimuli

▪ conditioned stimuli presented with unconditioned

▪ don’t forget just mask

▪ conditioned stimuli- bell no longer followed by food

▪ spontaneous recovery- you learn they’re no longer connceted- after further  period of time without connection and no further trials- once you ring the bell the  dog says wait a sec and remembers

▪ conditioning happens most officiently with optimum interval- half second if too  long pairing is decreased- if it’s too short it’s hard to associate if the food or bell

come first

▪ backward pairing- food first then bell- it’s reversed

▪ contingency- 40 presentations of bell tone and 20 random shocks ▪ 40 presentations of bell tone and 20 shocks are always follow by the bell  tone

▪ difference in conditions  

▪ the rats can’t associate in the first ones since it’s random

▪ don’t know when to expect

▪ in the second condition the bell is always followed by shock

▪ the bell is a safety signal and they get ready for the shock

▪ rats prefer second option  

▪ rats like to learn

▪ associations provide a basis for expectation

▪ we can adjust our learning through surprises  

▪ in surprise you get more than you expect and then you increase  expectation

▪ get what expected and don’t adjust

▪ get less than expected and decrease expectations- weakening of  association

the blocking effect- if stimulus doesn’t give new info the animal will learn nothing ▪ mate will come with sound

▪ light turns on when hiss- light is conditioning but it’s not when you put the light  alone there is no sexual arousal because it knows the sound already informs him  about it and the light didn’t provide new info  

▪ don’t learn anything about light it already learned about his sound and light isn’t  new

▪ neal miller experiment- participants shocked every time they say the letter T  galvanic skin response

⁃ letter 4 isn’t followed with 4 when told to say and theres no galvanic  response

⁃ T 4- thought of stimuli T leads to skin response can lead to physical  consequences

▪ Relationship with conditioned response and unconditioned response- bell is  conditioned stimulus- conditioned tells animal to get read and the conditioned  response is an adjust for unconditioned stimulus

▪ light always followed by shock- be alert for body- condition response causes  body to adjust itself

▪ helps animals for digestion- body gets ready to digest food when it hears bell ▪ rats alert when they here it- work back wards as well

▪ compensatory response- anticipate respiratory suppression with heroine activate respiratory sensors to higher level because you may need to do higher  dose get ready for it they know it’s coming

▪ drug addict- gets his heroine fix- heroine is opioid exogenous- unconditioned  stimulus

⁃ unconditioned response is euphoria and respiration suppression- like a  reflex not learned

⁃ tolerance is developed- continued use- body reduces indigenous opioids lower level second time the addict injects needle more drug is needed for  same high- body tries to reduce indigenous amounts of opioids used progressively up dose

⁃ resperatory suppression increased to dangerous level

⁃ conditioned stimulus ^

⁃ all learned in one location- when the same thing happens in a new  location there are no advanced warnings for addict

⁃ does higher dose in london instead of ny body can’t balance it out no  compensatory response

⁃ leads to overdose and die

▪ instrumental conditioning- form of learning  

⁃ like classical conditioning 3 forces

⁃ when performed desired thing reward if not punished

⁃ dog training

⁃ to create voluntary behaviors

⁃ primary reinforces- food water

⁃ social reinforces- smile- joke funny

⁃ taste aversion- belongingness in rats- first give them sweets and water  then X-ray and make them sick- they then associate vanilla taste with  being sick- taste aversion between stimulus and outcome

▪ belongingness pigeons- different responses seek different outcomes- peck a  button to receive food or mate

▪ different peck gives different reward- open mouth food- beak water- cooing sound  and peck gives mate

▪ belongingness happens with rats and pgieons

▪ aplysia- done with sea molesk- learning depends on neuroplasticity- neurons  and synpapses change with different experiences- become more sensitive to  signals and connections can be made

⁃ learn to fear something- our neurons send stronger signals and quicker  and better at communicating

⁃ study with aplysia- learn form light touch

⁃ any time you do a light touch you get a tail shock

⁃ learn to retract siphon and gill- after repeated trial aplysia only retracts it  when light tough occurs- it’s conditioned in

▪ when look t sensory neurons they release more sensory neuron before  condition

▪ presynaptic facilitation- when conditioned

▪ response to control depression- gaining a response to a control- done with  rats

⁃ about how a particular rat presses a lever for pellets

⁃ theres a particular rat that’s depressed and doesn’t seem to learn ⁃ coons wants to make the rat press the lever for pellets

⁃ puts in skinner box

⁃ mouse isn’t learning

⁃ it’s confused and running away

⁃ then he used a shaping procedure

⁃ in this procedure the pellet dispenser makes a sound

⁃ then quickly drops pellet under the rats nose and rat eats it

⁃ slowly the rat learns there’s an expectancy that after the noise a pellet will  come

⁃ after that coons makes the sound but instead of giving the pellet he gives  a delay

⁃ the rat expects it right after though

⁃ it then gets frustrated

⁃ when he gets curious coons rewards him

⁃ slowly coons can get the rat to move in the direction of the pellet ⁃ after an hour he takes on the challenge and coons shapes the rat to push  the lever

⁃ he gets the pellet

⁃ after 45 mins the rat is still pressing the bar even though it’s full- they think  that because the rat was satisfied with his feeling of control over the lever ⁃ rat was just curious to see if it could make the thing happen again ⁃ after 3 days it’s not depressed and its a completely different rat ▪ in depression people get the feeling of helplessness

▪ if we get people to accomplish something or learn something they’ll no longer be  depressed

▪ apparent motion- moon example- induced motion- dark night seems like moon is  drifting away in the clouds but the clouds are moving faster