Transcript Powerpoint
PSY402 Theories of Learning Chapter 7 – Theories and Applications of Appetitive Conditioning Operant Conditioning The nature of reinforcement: Premack’s probability differential theory Response deprivation theory Behavioral economics: Behavioral allocation – blisspoint Choice behavior – Herrnstein’s matching law. Momentary maximization theory Delay-reduction theory Probability-Differential Theory Premack – a reinforcer can be any activity that is more likely to occur than the reinforced behavior. Manipulators vs eaters High probability behaviors can be used as reinforcers of low probability behaviors. Frequency of the reinforcer decreases when it is made contingent on another response. Response Deprivation Theory Timberlake & Allison – deprivation occurs when an activity is used as a reinforcer and is not freely emitted. The activity is reinforcing because it satisfies the deprivation created. The animal tries to return to its predeprivation level of responding. Activities can be reinforcing even if their baselines were not higher. Behavioral Allocation Blisspoint (paired basepoint) – the free operant level of two responses. Unrestricted responding with two choices of behaviors. Blisspoint is used to figure out how much behavior an animal will engage in to obtain a reward. Animals try to get as close to the blisspoint as possible. Problems with Contingencies Blisspoint is established by looking at behavior before a contingency is established. The established contingency must take blisspoint into account or it may not increase desired behavior. Choice Behavior Herrnstein’s matching law – describes how animals act when they have two or more choices. Different responses have different schedules of reinforcement. Responding to each choice is proportionate to the reinforcement for each choice – after learning. This can be expressed mathematically. Mathematical Expression The formula for the matching law is: where R1 and R2 are the rates of response for two alternative responses And r1 and r2 are rates of reinforcement for those responses Delayed Gratification Why does anyone choose a smaller reward part of the time? Animals and people typically choose a small immediate reward over a larger delayed reward. Large rewards are selected when: The choice is made in advance of reward. Reinforcers are not visible or reward is already present (pleasurable activity). Complexities of the Matching Law Maximizing law – sometimes the aim is to obtain as many rewards as possible. Explains FR-10 vs FR-40 schedules. Doesn’t work for VI vs VR schedules. Momentary maximization theory – choose best alternative at the time. Delay reduction theory – choose what will get the reward the fastest. Contingency Management Assessment phase – determine the frequency of behavior and the situations in which it occurs. Contracting phase – specifies the relationship between responding and reinforcement. Management phase – implement the contract and evaluate results.