Kin 1080 Final Exam - exam PDF

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Kin 1080 Final Exam – Start Slide 158

Pre-lecture Overheads: Birthday Asymmetry (Mateo) Birthday Asymmetry Study  

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People involved in various levels of soccer in Spain. o Mujika is the researcher They wrote their birthdays down into quartiles (Q1, Q2, Q3, Q4) in the school cause there is an equal amount o As the levels (divisions) go up it starts to become less even and more of a robust asymmetry In La Liga, the vast majority of individuals who are reaching these high levels and born in the first 3 months. In La Liga its 32% (first quarter) vs 13% (last quarter). Physical maturity allows people to dominate at young ages. Kids who are physically more mature during youth sport. These kids get better coaching and more attention from coaching and they also enjoy it more.

Information Processing and Response Programming 3 stage model for information processing (Slide 158) 

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Model: o Steps:  Stimulus identification/detection  Response Selection  Response Programing  Involves high level cognitive control o Stages of information processing are serial and discrete SR - stimulus response alternatives o Possible choices In a choice reaction time task, each stimulus is linked to a particular response. As you increase the number of SR alternatives you increase the length in reaction time o It has everything to do with the response selection stage. o The more possible choices you can choose from, the longer it takes to make the decision Hick's Law (1952) – Slide 172 o Choice reaction time task o Results: RT increased by 150ms every time the SR alternatives doubled  Thus, relationship between choice RT and the logarithm of the SR alternatives is linear. o Stimulus bits (x axis) 1,4,8,16 stimulus response  There is a very linear increase in reaction time as increasing stimulating bits o Choice RT=a + b[Log2(N)]  A and B are empirical constants

B is the slope (change in y associated with a one unit change in x), a is the y intercept o Log2(N) is index of difficulty (number of bits you have to process)  Formula will be given  A bit is the amount of information required to reduce uncertainty by half – Slide 174 Will ask us to calculate it when given a and b but he will give us numbers like, 2, 4, 6, 8, 16, 32, 64, 128 to determine index of difficulty. o Remember for BEDMAS, you multiply before you add. The intercept and the slope change on the basis of some variables o The slope is associated with reaction time for younger adults is much shallower than for older adults. 153 slope vs 165 (steeper) o The effector you use to perform the task also influences the slope. Slope is much shallower for a manual task vs using their feet to perform a similar type task People that are well practiced will have a much shallower slope than an individual with limited practice. Age, effector and practice influence the slope of Hicks equation *** o

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  Stroop Effect: 

Incompatible mapping between the colored ink and the meaning of the word. This is a non-standard task.  You increase the number of errors (and reaction time) when you have a non-standard task  For a non-standard task, the errors people make have a profound outcome in any domain. The final exam will have 2 abstracts to analyze o Independent and dependent variables -------------------------------------------------------------------------------------------------------------------------------------Stroop effect – SR (stim response) Compatibility  

Extent to which stimulus and response are associated in a natural way Incompatible mapping between colour and words – non-standard task

Another type of compatibility issue – Spatial compatibility   

Video: Picking up iron instead of phone Example: Nuclear control center – near meltdown due to lever turning STUDY: PAUL FITTS (FITTS AND SEEGAR STUDY) o Reaction time procedure o 2 Conditions:  A: Spatially compatible (lights aligned – high SR compatibility)  B: Spatially incompatible (lights crossed – low SR compatibility) o Finding: Subjects were faster and make fewer errors for a spatially compatible task as opposed to an incompatible environment  Mediated by the frontal cortex

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Pro and anti-saccades (Heath studies this ***) o Pro-saccade – simple task with SR compatibility – most frequent motor response we perform everyday (approx. 230 ms) o Anti-saccade – computationally very difficult because we must override our pro-saccade (typically 320 ms) Munoz and Everling Study graphs – frequency histograms (Slide 177) o Overlap paradigm – you have a fixation cross and a target comes up – stimulus and target and fixation cross overlap with each other  We have neurons in our superior colliculus called fixation neurons – as long as you have something to fixate on they are on BUT they also prevent you from making a saccade when they are active (locked onto fixation)  Typically around 100 ms difference between pro and anti saccads in an overlap paradigm o Gap paradigm – Fixation cross comes on and then it goes away – 200 ms later a target appears (does not overlap)  As soon as fixation point is extinguished, fixation neurons are no longer active. As soon as the stimulus is on, the saccad neurons are innervated quickly which results in shorter reaction times for both pro and anti saccad tasks  With a gap paradigm, both saccads have shorter reaction times  In terms of anti-saccads, there is also a cost in a gap paradigm – MORE ERRORS (instead of anti-saccading, they accidentally pro-saccad)  It is computationally more difficult to anti-saccad in a gap paradigm than an overlap paradigm  Know: overlap paradigm has longer reaction times, gap paradigm has shorter reaction times; if you remove fixation cross the fixation neurons no longer fire, cost of this in anti saccades is more errors Pro-saccades are stimulus driven o PATHWAY (Slide 178):  Retina  Superior colliculus (w/ saccad neurons)  reticular formation w/ alpha motor neurons  eye muscles for pro saccad  Pro-saccad rxn times are short because the pathway is simple Anti-saccade pathway – cortically driven o Uses lateral geniculate nucleus o Retina  LGN  Visual cortex  parietal cortex (sensory to motor interface)  frontal cortex  Superior colliculus  reticular formation  eye muscles for anti-saccade o Response suppression – you must cognitively inhibit your desire to perform a pro-saccad – occurs in frontal cortex o Vector inversion – mirroring – entails activation of the parietal cortex  Moving directly away from something? o Anti-saccade is used to see if someone with schizophrenia’s medicine is working  If they make a lot of anti-saccade errors, then their frontal cortex is not working well and their medicine needs to be adjusted  Have an over or under activated frontal cortex

RESPONSE PROGRAMMING STAGE:

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Following response selection, the action must be translated into appropriate muscular signals to achieve task goals Franklin Henry Study (Henry and Rogers – Slide 179): Looking at length of time required to program a response o Press a button when a light came on (or lift finger from it) o Press a button/lift finger and then reach up and grasp a tennis ball o Press a button/lift finger and grasp a tennis ball and then a second tennis ball They manipulated task complexity Results: o RT increased as a function of task complexity o Reflects time necessary to prepare the movement during the response-programming stage

Attention TOPIC 7 – ATTENTION (Slide 180) Attention: Focalization and limitation of information processing resources COUNT NUMBER OF PASSES: 13 Attentional blindness – all resources put to focusing Change blindness – Doesn’t draw attention when changes slowly 

Sudden changes engage your superior colliculus and causes pro-saccades

NIESSER STUDY – Attentional control doesn’t have to be consciously mediated    

Given a list of 50 words – 10 words would be paired with a shock 6 months later they were shown 100 words and a couple of the words were paired with the mild electric stimulus MEASURING GALVANIC SKIN RESPONSE (GSR) – measure of skin conductiveness Skin conductance increases in state of high anxiety – primes you to get ready for an action o Participants showed increase in GSR when 10 words were shown on screen even though none of them reported the awareness o Attention and consciousness are independent of each other

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Neissser study recap: Attention + consciousness are not necessarily linked together o Definition revisited (Slide 182 revisited) o Some models suggest that attention is a single resource that has a limited processing capacity (finite) – SLIDE 183 – PRIMARY MODEL o Limited processing resource with limited capacity/supply  If someone performs multiple tasks, if all the tasks combined do not exceed the limited pool of attentional resources, they can be performed at an optimal level  E.g. walking and talking on the phone

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Driving example o Can be driving while talking on the phone but requires a tiny bit of attentional capacity left in case you need to swerve to avoid an accident o Situation changes in heavy snowfall with lots of traffic – optimal functionality is lost (detriment in performance in all tasks)  This is THE theory that led to banning cellphones while driving – but applies to conversations with people in the car as well (but mobile phone is worse) o Passengers can modulate their required attention depending on the road conditions – people on the phone cannot do this o Hands free devices do not help much in this case Information processing (Attention for control) – Slide 186 o Limited capacity processing channel o Limitations in the number of activities that can pass through channel at the same time o Serial vs parallel processing  Stimulus Identification  Response selection  Response programming/execution o Each stage of processing takes time o There is a bottleneck somewhere in the 3-stage model of information processing – different models suggest different locations  AN EARLY MODEL OF ATTENTIONAL CONTROL STATES – *** Bottleneck occurs at stimulus identification – slide 189  States that there is a filter that occurs at this stage that allows only one sensory resource channel to enter the model at any one time (serial processing) (WELFORD Approach)  Consider the Cocktail party phenomenon: If you are at a party and talking to someone 1 on 1 with full attention, you can hear people around you but you cannot determine what they are saying but if someone says your name, your attention switches to them at the cost of losing your attention to the person in front of you – not all information is FULLY processed – DEVELOPED BY WELFORD  Other theory (BROADBENT) – Suggests that we have both parallel and serial processing and that we can process multiple stimuli in parallel in the identification stage but it becomes serial at the response selection stage (only 1 channel can enter the selection and execution/programming stage)  Difference in models: o Where the filter lies (Stimulus identification or response selection) o Types of processing after the filter (serial or parallel)  Consider the Stroop effect - the reason why people have errors in the Stroop task is because they must process both the colour of the ink and the actual word and you must decide which of these passes the filter

Attention as Multiple Resource:  There are multiple attentional resources available to us: o Pool for spatial activities (Resource A) o Pool for cognitive activities (Resource B) o Pool for motor activities (Resource C)  PSYCHOLOGICAL REFRACTORY PERIOD (PRP)  Physiological refractory period – when the neuron must take time before it can fire another action potential  Barry sanders video:

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Sanders can deak out players very quickly

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This is a clear demonstration of psychological refractory

Second example: goalie o

Almost became frozen and couldn’t move over to stop the ball

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If you can get a fake going (get a defense to go in one direction, they will attend to that action … they don’t have any resources left over to react to the other direction … they are in a state of psychological refractory  can’t attend to the other stimulus/won’t move)

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Lab example:

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Pressing button as quickly as they can

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Stim 1 and stim 2 on their own would result in the same reaction time

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If you present stim 1 and 2 in close temporal proximity 

Stim 2 is presented 80 ms later

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Participant is told to react as quickly as possible to both stimulus

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Response to stim 1 has same reaction time as they would without stim 2

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Response to stim 2 has about 100 ms increase in reaction time (if stim 2 was on it’s own it would have been the normal 150 ms, but when presented with stim 1 you get the large increase in reaction time)

Psychological Refractory Period (PRP) 

Delay in responding to the second of 2 stimuli presented in rapid succession

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About interference in response selection (delay in selecting response for stimulus 2) and organization of response o

Shows how attention is a limited capacity resource (single capacity attentional resources)

Late Theory: 

Filter is in the response selection

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Have 2 stimuli come in

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Stimulus 1 can get processed without any delay  passes all the way through

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Stimulus 2 must wait around response selection stage until everything is processed for stimulus 1 o

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Therefore, there is a very large increase in reaction time

This is a very robust feature o

Everyone experiences this  why don’t offenders try and do this to defense more? 

Only some athletes can move quick enough so that there’s close enough temporal proximity between stimulus 1 and 2

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Sanders had a lot of lateral speed to help get by

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How to use the PRP in sport 

Stimulus 1 = Fake move o

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Want opponent to process fake move and organize a response

Stimulus 2 = actual move o

Capitalize on PRP process to delay response time to actual move

Slide 198 graph:  

Delay between the stimuli: x-axis Reaction time for response 2 (ms) (y-axis) o Red: baseline o Black: Stimulus 1 involved o If difference between 2 onsets is between 0 and 50 ms, you don’t get delay  They see them being onset at the same time and processed simultaneously (don’t get refractory) o If difference is between 50 and 175 ms (75 ms is best), you get a delay  Far enough apart to have increase in reaction time to response 2 ------------------------------------------------------------------------------------------------------------------

Temporary Switch into Open and Closed Loop Motor Control LAURA /MATEO: March 17th 

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Open loop motor control (Skip to Slide 289): o

Can do a task without even looking (no sensory feedback – preprogrammed)

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I.e. You can grab a drink without looking at it because it’s something you’ve done so many times

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It’s familiar to you; you know where it is; you can implement that action without any sensory info

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Definition: A control system with preprogrammed instructions to an effector that does not use: o

1. Feedback

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2. Error detection

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3. Correction mechanisms

Closed loop motor control (Skip to slide 236): o

If you were to pick up a small pin on a desk top, you need vision and tactile feedback to do this successfully

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Definition: (Will be revisited after)

*Exam question on this… will give us a movement and we must say if it’s open or closed* Open Looped Motor Control: 

Ballistic (performed very fast such as hurdles) and well learned actions typically are the ones where you don’t need eccentric feedback

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Elements of an open looped control system:

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Reference mechanism not present

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Feedback unavailable

Study: Veterans who had wounds to their back (Sherrington vs Rothwell Studies) o

The dorsal root ganglion specializes in sensory info from muscles to spinal cord

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Many of these veterans had lost their dorsal roots  had no ability to transmit sensory info from muscles to spinal cord 

Dorsal root lesions

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You would think they shouldn’t be able to walk, but they could and could do it without looking at their feet o

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Suggests that an action can occur in an open loop fashion without feedback

Sherrington’s view thought that dorsal root sectioning would prevent movement (early studies, while Rothwell’s view (later studies) shows that individuals can program actions without sensory input

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Study: Dorsal lesions as result of a virus

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Iain Waterman: o

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Picked up an odd virus which selectively destroyed all of the roots associated with his dorsal root ganglion… couldn’t receive any sensory info from his muscles 

Took him about 3 or 4 years to be able to move again

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Was able to learn how to walk and perform functional activities of daily living

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An example of how you can perform actions without feedback (in this case from your muscles)

Had troubles buttoning his shirt etc.  had to relearn actions that we would do without vision

Study: Two researchers in the Soviet union (Slide 292 – Mesencephalic (midbrain) cat supported on a treadmill) 

Looked at gait formation in cats

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Severed midbrain of cats, so info from cortex couldn’t go through midbrain on way to spinal cord o

Cats therefore had no muscle tone (quadriplegic cat)

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Locomotor strip: o

Nexus between the brain stem and the spinal cord, below the level of the transection 

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This strip/area allows a cat to perform a rhythmical action (like walking)

They had to bolt them to a treadmill 

When they turned the treadmill on, the cat would initially drag its feet, then eventually it would start walking

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Would turn the treadmill up from walking to running… and the cat would start running even without info coming from the cortex (can make the transition)

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Suggests that there’s something specific about our brain stem that allows us to control rhythmic and stereotyped open loop actions 

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Dogs perform a rhythmic and stereotyped action of wagging their tail

Led to the idea of Central Pattern Generators (slide 293) 

There’s a cluster of neurons somewhere in the brain stem that allows us to control open looped movements (rhythmic and stereotyped movements) 

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Control without higher movement centers

Central Pattern Generators: 

Have a neuron that’s going to start a cascade o

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This neuron usually would get info from higher cortical centers  would trigger ...