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| Immediate Value, Delay of Reinforcement and Change in that Delay Determine Overall Value: Developmental and Clinical Implications |
| Sunday, May 25, 2008 |
| 2:30 PM–3:50 PM |
| Metra |
| Area: EAB/CBM; Domain: Basic Research |
| Chair: Michael Lamport Commons (Harvard Medical School) |
| CE Instructor: Michael Lamport Commons, Ph.D. |
| Abstract: Traditionally, the concept of utility comes from economics. It is the probability of obtaining a reinforcer times its value. In behavior analysis, we use rate of reinforcement and immediate value. Here we discuss a four variable general discounting model that has properties of a number of economic and behavioral theories. The value of reinforcement, Ai, reflects the immediate value of reinforcement. The value varies with the goods and services delivered the individuals interests, drives, ambition and clinical state. Clinically, depression lowers the value. The second variable is delay as found in discounting models. It is a negative power function. Clinically, over discounting is associated with impulsivity and character disorders. Addicts find the short term pain of withdrawal unbearable even considering the cost of addiction. The third variable, change in delay is represented here as changes in the time between reinforcements rather than the change in probabilities that is often characterized as risk. Some people are oversensitive, fearing dying in a plane crash or from terrorist bombing more than the constant risk of smoking or lack of exercise. Clinically, the hording kind of OCD is associated with fear of immediate loss of giving something up rather than benefits of having space and order. |
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| General Discounting Model for Overall Value: Clinical and Developmental Implications. |
| MICHAEL LAMPORT COMMONS (Harvard Medical School) |
| Abstract: Traditionally, the concept of utility comes from economics. It is the probability of obtaining a reinforcer times its value. In behavior analysis we are more considered with continuous time rather than discrete choice. So the value of a reinforcement schedule has been characterized by the matching law. Here we discuss a general discounting model that has properties of a number of economic and behavioral theories. The value is the sum of the probabilities of individual reinforcing events divided by the delay (raised to some power) and the relative change in delay. Relative change in delay is the change in delay divided by the delay. There are than four parameters, one for each variable. Each variable represents a major function of the organism. There is variability among organisms with respect to these parameters. In people, some of this variation may be benificial and other variations may be associated with behavioral problems. |
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| The Role of Immediate Value of Reinforcement on Overall Value: Clinical and Developmental Implications. |
| ANDREW MICHAEL RICHARDSON (The Dare Institute) |
| Abstract: The immediate value, Ai, reflects the immediate value for any given reinforcement. This value may vary from individual to individual with respect to the event serving as the reinforcer. The reinforcing or punishing value of the delivery of various goods and services may have different values depending on a number of variables. Therefore the value of Ai is determined by the individuals’ evolutionarily programmed and acquired drives, interests, current drive states, ambition and clinical state. A person with depression may have low values of Ai in general. A person is described as Enterprising if money is a relatively powerful reinforcer. Another person is described as Investigative if discovering new knowledge is a relatively powerful reinforcer. A biological scientist is described as ambitious in pursuing the discovery of a vaccine for HIV/AIDS, so any outcome will only be viewed in light of progress towards that major goal. Thus, a reinforcer will only be seen as valuable if it reflects advances in knowledge towards finding a vaccine. Each local reinforcer will not cause satiation until a vaccine is found, but it will maintain the rate of searching for new insight into the problem, and only in this way it is valuable. |
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| The Role of Delay on Overall Value: Clinical and Developmental Implications. |
| ANDREW MICHAEL RICHARDSON (The Dare Institute) |
| Abstract: The second variable di, represents traditional delay of reinforcement discounting. It is a negative power function, with k1dk3 in the denominator. When k3 = 1, it reduces to the hyperbolic discounting model. In economics the probability of a reinforcer is replaced by the rate of reinforcement. The time between reinforcers is often represented as delay of reinforcement. Self control literature shows that adults who over discount tend to be impulsive and may have personality disorders whereas for children this is normal. When young children get hurt, they cry as if their pain will last for ever, but the minute the pain leaves them they may act happy and joke. In addiction, the immediate joy swamps the long term pain of the addiction. The short term pain of withdrawal is unbearable even compared to the long term cost of addiction. In spending, the immediate feeling of satisfaction outweighs the troubles of being in debt. In psychosis, people might not even register potential reinforcing stimuli even with zero delay. Whereas these people will have a steeply falling curve, ambitious people will have relatively flat curves for discounting because they are willing to wait for results. |
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| The Role of Change in Delay on Overall Value: Clinical and Developmental Implications. |
| MICHAEL LAMPORT COMMONS (Harvard Medical School) |
| Abstract: In economics, probability characterizes risk. In behavior analysis, the equivalent is change in delay of reinforcement. Here we track the relative changes in delay, ?di /di as the time between reinforcements divided by the delay rather than the change in probabilities. The value of a reinforcer is lowered when there is an increase in relative delay. When people engage in avoidance of an increase in relative delay, this is equivalent to risk avoidance. The difference is that the value being lowered due to an increase in delay is a direct perception of value, whereas avoidance of risk occurs when people are presented with the future possibility. Consider the risk of dying in a plane crash or terrorist attack. With these events there seems to be a rapid change in the density of punishment. Contrast this with the acceptance of a high rate of death from smoking or inactivity. Many compulsive collectors and hoarders cannot give something up because the immediate loss is too great compared to the long term benefit of not having to store it. They also may have great difficulty in making decisions or even acting on the ones that were decided. |
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