Biomedical subjects

Howard Rachlin

Publications and source records attributed to Howard Rachlin.

11 recordsLinked to original sources

PubMed2006

In what sense are addicts irrational?

Rationality is here considered from a functional viewpoint: How may the concept of rationality be best used in talking about addictive behavior? The article considers rationality in terms of overt behavioral patterns rather than as a smoothly operating logic mechanism in the head. The economic notion of rationality as consistency in choice - the property of exponential time discount functions - is examined and rejected. Addicts are not irrational because of the type of time discount function that governs their choices-or even because of the steepness of that function. Instead, rationality is here conceived as a pattern of predicting your own future behavior and acting upon those predictions to maximize reinforcement in the long run. Addicts are irrational to the extent that they fail to make such predictions and to take such actions.

Awareness↗

PubMed2006

Social discounting.

The amount of money a person was willing to forgo in order to give 75 dollars to another person decreased as a hyperbolic function of the perceived social distance between them. Similar hyperbolic functions have previously been shown to describe both time and probability discounting.

Adult↗

PubMed2006

The influence of prior choices on current choice.

Three pigeons chose between random-interval (RI) and tandem, continuous-reinforcement, fixed-interval (crf-FI) reinforcement schedules by pecking either of two keys. As long as a pigeon pecked on the RI key, both keys remained available. If a pigeon pecked on the crf-FI key, then the RI key became unavailable and the crf-FI timer began to time out. With this procedure, once the RI key was initially pecked, the prospective value of both alternatives remained constant regardless of time spent pecking on the RI key without reinforcement (RI waiting time). Despite this constancy, the rate at which pigeons switched from the RI to the crf-FI decreased sharply as RI waiting time increased. That is, prior choices influenced current choice-an exercise effect. It is argued that such influence (independent of reinforcement contingencies) may serve as a sunk-cost commitment device in self-control situations. In a second experiment, extinction was programmed if RI waiting time exceeded a certain value. Rate of switching to the crf-FI first decreased and then increased as the extinction point approached, showing sensitivity to both prior choices and reinforcement contingencies. In a third experiment, crf-FI availability was limited to a brief window during the RI waiting time. When constrained in this way, switching occurred at a high rate regardless of when, during the RI waiting time, the crf-FI became available.

Animals↗

PubMed2006

Notes on discounting.

In general, if a variable can be expressed as a function of its own maximum value, that function may be called a discount function. Delay discounting and probability discounting are commonly studied in psychology, but memory, matching, and economic utility also may be viewed as discounting processes. When they are so viewed, the discount function obtained is hyperbolic in form. In some cases the effective discounting variable is proportional to the physical variable on which it is based. For example, in delay discounting, the physical variable, delay (D), may enter into the hyperbolic equation as kD. In many cases, however, the discounting data are not well described with a single-parameter discount function. A much better fit is obtained when the effective variable is a power function of the physical variable (kDS in the case of delay discounting). This power-function form fits the data of delay, probability, and memory discounting as well as other two-parameter discount functions and is consistent with both the generalized matching law and maximization of a constant-elasticity-of-substitution utility

Humans↗

PubMed2004

The behavioral economics of violence.

From the viewpoint of teleological behaviorism the first question to ask in attempting to understand any behavior, including violent behavior, is: What are its contingencies of reward and punishment? Or, to put the question in economic terms: What are the short-term and long-term costs and benefits that such behavior entails? Let us therefore consider the costs and benefits of youth violence. Among the short-term costs of violent behavior are the physical effort of the act, the possibility of immediate physical retaliation, immediate social disapproval, and the opportunity cost of other social acts that the violent behavior takes the place of (you can't be affectionate and violent at the same time, for instance). Among the immediate benefits of violent behavior are the intrinsic satisfaction of the violent act itself and any extrinsic benefit; if A violently appropriates B's new sneakers then obtaining the sneakers reinforces A's violence. These immediate benefits may well outweigh the costs in many contexts. Among the long-term costs of violent behavior are delayed retaliation, possible social disapproval and loss of social support, rejection from a social group, job loss, and health risks associated with a violent lifestyle. Among the long-term benefits are long-term intimidation of others (your neighbor is less likely to build a fence on your property if you have a reputation for violence), and a possibly exciting lifestyle. These long-term benefits may well be outweighed by the long-term costs. Opposition of long-term net costs to short-term net benefits, where it exists, creates a personal self-control trap: Overall satisfaction may decrease monotonically with rate of the target behavior but, regardless of its rate, the immediate satisfaction of doing it is always higher than that of not doing it. In the case of violent behavior, this trap is exacerbated by the fact that as a person's violence increases, net immediate reinforcement also increases (due to membership in violence-reinforcing subgroups). This contingency fits the "primrose path" addiction model of Prelec and Herrnstein. Violence is thus a paradigm case of behavioral addiction. I consider three ways of controlling such addictive behavior: by punishment, by extinction, and by substitution. The problem with punishment in the case of violence is that physical punishment tends to increase violent behavior while incarceration drives the punished person into the very social subgroup (the prison culture) where violence is maximally reinforced. The problem with extinction is that the immediate benefits of violent behavior are largely intrinsic and some costs (immediate retaliation by unidentified others) are difficult to control. The best way to control violent behavior, as well as other addictive behaviors, is by decreasing the price of economic substitutes. There is much evidence that addictions, such as to cocaine, heroin, alcohol, and tobacco, may be reduced by decreasing the price of social support. The same is predicted for violent behavior--either by providing social support directly or by training in social skills. In addition, in considering control of violent behavior, we need to examine the immediate benefits and long-term costs to society of having violent individuals and violence-reinforcing subcultures among us. And we need to act to reduce our own dependence on those benefits.

Behavior, Addictive↗

PubMed2004

Contingencies of reinforcement in a five-person prisoner's dilemma.

As in studies of self-control, a tit-for-tat contingency in an iterated prisoner's dilemma game creates a conflict between maximization of local and global reinforcement. The present experiments examine this conflict in a multiplayer prisoner's dilemma game. Versus tit for tat, cooperation corresponds to self-control; defection, always immediately reinforced, corresponds to impulsiveness. Three experiments examined sensitivity of behavior to the global reinforcement contingency imposed by tit for tat. Undergraduates played a five-player prisoner's dilemma game against four dummy players programmed to play tit for tat or randomly. With tit for tat, a player's cooperation (or defection) increased dummy players' cooperation (or defection) on subsequent trials-reinforcing cooperation and punishing defection in the long run. Participants cooperated at a higher rate when the dummy players played tit for tat than when the dummy players played randomly. These results are consistent with findings in corresponding studies of self-control. Some participants, caught in a trap of mutual defection with the tit-for-tat playing dummy players, came to cooperate when the tit-for-tat contingency was reset ("forgiving" participants' previous defections) during a pause in the game. This increase was a result of the combined effects of a pause and reset; neither pausing nor resetting independently resulted in an increase in cooperation.

Adult↗

PubMed2003

Learning by pigeons playing against tit-for-tat in an operant prisoner's dilemma.

Each of four pigeons was exposed to a single random-ratio schedule of reinforcement in which the probability of reinforcement for a peck on either of two keys was 1/25. Reinforcer amounts were determined by an iterated prisoner's dilemma (IPD) matrix in which the "other player" (a computer) played tit-for-tat. One key served as the cooperation (C) key; the other served as the defection (D) key. If a peck was scheduled to be reinforced and the D-key was pecked, the immediate reinforcer of that peck was always higher than it would have been had the C-key been pecked. However, if the C-key was pecked and the following peck was scheduled to be reinforced, reinforcement amount for pecks on either key were higher than they would have been if the previous peck had been on the D-key. Although immediate reinforcement was always higher for D-pecks, the overall reinforcement rate increased linearly with the proportion of C-pecks. C-pecks thus constituted a form of self-control. All the pigeons initially defected with this procedure. However, when feedback signals were introduced that indicated which key had last been pecked, cooperation (relative rate of C-pecks)--hence, self-control--increased for all the pigeons.

Animals↗

PubMed2002

Teaching and learning in a probabilistic prisoner's dilemma.

The prisoner's dilemma is much studied in social psychology and decision-making because it models many real-world conflicts. In everyday terms, the choice to 'cooperate' (maximize reward for the group) or 'defect' (maximize reward for the individual) is often attributed to altruistic or selfish motives. Alternatively, behavior during a dilemma may be understood as a function of reinforcement and punishment. Human participants played a prisoner's-dilemma-type game (for points exchangeable for money) with a computer that employed either a teaching strategy (a probabilistic version of tit-for-tat), in which the computer reinforced or punished participants' cooperation or defection, or a learning strategy (a probabilistic version of Pavlov), in which the computer's responses were reinforced and punished by participants' cooperation and defection. Participants learned to cooperate against both computer strategies. However, in a second experiment which varied the context of the game, they learned to cooperate only against one or other strategy; participants did not learn to cooperate against tit-for-tat when they believed that they were playing against another person; participants did not learn to cooperate against Pavlov when the computer's cooperation probability was signaled by a spinner. The results are consistent with the notion that people are biased not only to cooperate or defect on individual social choices, but also to employ one or other strategy of interaction in a pattern across social choices.

Journal Article↗

PubMed2002

Rule-governed versus contingency-governed behavior in a self-control task: effects of changes in contingencies.

Rule-governed behavior is typically acquired faster than contingency-governed behavior but is less sensitive than contingency-governed behavior to unverbalized contingency changes. The present study investigated these relationships in a computer task frequently used to study human self-control. Instructions for one group of participants contained a hint about how to maximize long-term reinforcement; the other group performed the task without the hint. Participants given the hint came closer to maximizing reinforcement in the long term, but their behavior was less sensitive to an unsignaled contingency change than that of those not given the hint. The study shows that, like other complex behaviors, self-control may be contingency-governed or rule-governed.

Journal Article↗

PubMed2002

Altruism and selfishness.

Many situations in human life present choices between (a) narrowly preferred particular alternatives and (b) narrowly less preferred (or aversive) particular alternatives that nevertheless form part of highly preferred abstract behavioral patterns. Such alternatives characterize problems of self-control. For example, at any given moment, a person may accept alcoholic drinks yet also prefer being sober to being drunk over the next few days. Other situations present choices between (a) alternatives beneficial to an individual and (b) alternatives that are less beneficial (or harmful) to the individual that would nevertheless be beneficial if chosen by many individuals. Such alternatives characterize problems of social cooperation; choices of the latter alternative are generally considered to be altruistic. Altruism, like self-control, is a valuable temporally-extended pattern of behavior. Like self-control, altruism may be learned and maintained over an individual's lifetime. It needs no special inherited mechanism. Individual acts of altruism, each of which may be of no benefit (or of possible harm) to the actor, may nevertheless be beneficial when repeated over time. However, because each selfish decision is individually preferred to each altruistic decision, people can benefit from altruistic behavior only when they are committed to an altruistic pattern of acts and refuse to make decisions on a case-by-case basis.

Altruism↗

PubMed2002

Self-control by pigeons in the prisoner's dilemma.

Pigeons played a repeated prisoner's dilemma game against a computer that reflected theirchoices: If a pigeon cooperated on trial n, the computer cooperated on trial n + 1; if the pigeon defected on trial n, the computer defected on trial n + 1. Cooperation thus maximized reinforcement in the long term, but defection was worth more on the current trial. Under these circumstances, pigeons normally defect. However, when a signal correlated with the pigeon's previous choice immediately followed each current trial choice, some pigeons learned to cooperate. Furthermore, cooperation was higher when trials were close together in time than when they were separated by long intertrial intervals.

Animals↗