I) Midterm 2A) Tuesday, May 15B) Review Session1) Friday, May 11 @ 2:30-4pm2) Franz 1178C) Chapters 4 & 5 in the book as well as lectures on that materialII) Instrumental BehaviorA) Behavior that occurs because it was previously instrumental in producing a certain consequenceB) Appears to be goal directed1) Is actually goal directed in some cases2) Might be habitual rather than goal directedC) Response outcome contingency1) We learn new behaviors through a trial-and-error process2) Law of effect describes how the consequences of a behavior and increase or decrease the future probability of that behaviora) The outcome of response has an effect on learningb) If the stimulus is followed by a satisfying event, the association between the stimulus and the response is strengthened (and vice versa)c) The strength of the S-R association determines the probability of the response in the presence of the stimulusD) Thorndike’s cat-puzzle-box experimentsE) Discrete-Trial Procedures (W.S. Small)1) To study learning in rats2) Put the subject in one area, let them make a response, then pick the rat up and put it back in the start chamber each trial is discrete3) Straight-alley mazea) Measure running speed or latency to reach the goali) If time to reach the goal decreases, running speed must be increasingb) T-maze involves a choice or directioni) Consequences of the decision will influence future decisionsIf food is always placed on the left, or if there are different types of food on each sideF) Operant (Instrumental) Conditioning1) Skinner developed a free-operant procedure and the Skinner Boxa) Free-operant procedures allow the animal to repeat the instrumental response without constraint (the rat can keep pressing the button and keep getting food)b) Shapingi) Magazine training= food is delivered hereii) Attending to the leveriii) Touching the leveriv) Pressing the leverc) Measure response rate2) Two important factorsa) Response-reinforcer contingencyi) Positive (response causes the reinforce to be delivered)ii) Negative (response prevents a reinforce from being delivered)b) Valence of outcomei) Appetitive (something we like)ii) Aversive (something we don’t like)c) Positive reinforcementd) Negative reinforcementi) Escape response: taking action to prevent a bad situation that you’re inii) Avoidance: taking action to prevent a bad outcome that you anticipateiii) Omission: to decrease an instrumental response by creating a negative contingency between the response and appetitive outcomeDifferential Reinforcement of Other behavior (DRO)e) Response-outcome contingency table in the lecture slidesIII) Elements of Instrumental ConditioningA) Instrumental response1) Behavioral Variability vs. stereotypya) Initial variability in behavior is critical like natural selection acting on phenotypesb) Behavior generally becomes less variable over timec) Creativity can be reinforced as well2) Page & Neuringer (1985)a) Pigeons reinforced for pecking 2 response keys 8 times in a rowb) Variability group is reinforced for pecking in novel patternsc) Control group is reinforced for any sequence of peckingi) Link individuals from the variability and control groups to keep their reinforcement schedule equal and control for various factorsd) The data show that the individuals in the variability group do increase variability over several trials, the control group individuals do not—their variability decreasesi) Behavior becomes more stereotyped over timeii) We don’t know why the variability goes down in this particular experimentB) Reinforcer05/08/2012I) Midterm 2 A) Tuesday, May 15B) Review Session1) Friday, May 11 @ 2:30-4pm2) Franz 1178C) Chapters 4 & 5 in the book as well as lectures on that materialII) Instrumental BehaviorA) Behavior that occurs because it was previously instrumental in producing a certain consequenceB) Appears to be goal directed1) Is actually goal directed in some cases2) Might be habitual rather than goal directedC) Response outcome contingency1) We learn new behaviors through a trial-and-error process2) Law of effect describes how the consequences of a behavior and increase or decrease the future probability of that behaviora) The outcome of response has an effect on learningb) If the stimulus is followed by a satisfying event, the association between the stimulus and the response is strengthened (and viceversa)c) The strength of the S-R association determines the probability of the response in the presence of the stimulusD) Thorndike’s cat-puzzle-box experimentsE) Discrete-Trial Procedures (W.S. Small)1) To study learning in rats2) Put the subject in one area, let them make a response, then pick therat up and put it back in the start chamber each trial is discrete3) Straight-alley mazea) Measure running speed or latency to reach the goali) If time to reach the goal decreases, running speed must be increasingb) T-maze involves a choice or directioni) Consequences of the decision will influence future decisions-If food is always placed on the left, or if there are different types of food on each sideF) Operant (Instrumental) Conditioning1) Skinner developed a free-operant procedure and the Skinner Boxa) Free-operant procedures allow the animal to repeat the instrumental response without constraint (the rat can keep pressing the button and keep getting food)b) Shapingi) Magazine training= food is delivered hereii) Attending to the leveriii) Touching the leveriv) Pressing the leverc) Measure response rate2) Two important factorsa) Response-reinforcer contingencyi) Positive (response causes the reinforce to be delivered)ii) Negative (response prevents a reinforce from being delivered)b) Valence of outcomei) Appetitive (something we like)ii) Aversive (something we don’t like)c) Positive reinforcementd) Negative reinforcementi) Escape response: taking action to prevent a bad situation thatyou’re inii) Avoidance: taking action to prevent a bad outcome that you anticipateiii) Omission: to decrease an instrumental response by creating a negative contingency between the response and appetitive outcome-Differential Reinforcement of Other behavior (DRO)e) Response-outcome contingency table in the lecture slidesIII) Elements of Instrumental ConditioningA) Instrumental response1) Behavioral Variability vs. stereotypya) Initial variability in behavior is critical like natural selection acting on phenotypesb) Behavior generally becomes less variable over timec)