Effects of alternative reinforcement on human behavior: the source does matter

Competing theories regarding the effects of delivering periodic response-independent reinforcement (more accurately, response-independent points exchanged for money) on a baseline rate of behavior were evaluated in human subjects. Contiguity theory holds that these events decrease target responding because incompatible behavior is adventitiously strengthened when the point deliveries follow target behavior closely in time. Matching theory holds that response-independent points, like any other alternative reinforcer, should reduce target responding. On this view, temporal contiguity between target responding and response-independent point delivery is unimportant. In our experiment, four different responses (moving a joystick in four different directions) were reinforced with points exchangeable for money according to four independent variable-interval schedules. Different schedules of point delivery were then superimposed on these baselines. When all superimposed point deliveries occurred immediately after one of the four responses (the target response), time allocated to target responding increased. When the superimposed point deliveries could be delivered at any time, time allocated to target responding declined and other behavior increased. When superimposed points could never immediately follow target responses, time allocated to target responding decreased further and other behavior or pausing predominated. The findings underscore the contribution of temporal contiguity in the effects of response-independent deliveries of food, money, points, etc.     

A note on the equivalence of the graded response model and the sequential model

This paper concerns items that consist of several item steps to be responded to sequentially. The item scoreX is defined as the number of correct responses until the first failure. Samejima's graded response model states that each steph=1,...,m is characterized by a parameterb _h , and, for a subject with ability, Pr(Xh; )=F(–b _h ). Tutz's general sequential model associates with each step a parameterdh, and it states that Pr(Xh;)= _r ^=1h G(–d _r ). Tutz's (1991, 1997) conjectures that the models are equivalent if and only ifF(x)=G(x) is an extreme value distribution. This paper presents a proof for this conjecture.     

Resistance to change of operant variation and repetition

A multiple chained schedule was used to compare the relative resistance to change of variable and fixed four-peck response sequences in pigeons. In one terminal link, a response sequence produced food only if it occurred infrequently relative to 15 other response sequences (vary). In the other terminal link, a single response sequence produced food (repeat). Identical variable-interval schedules operated in the initial links. During baseline, lower response rates generally occurred in the vary initial link, and similar response and reinforcement rates occurred in each terminal link. Resistance of responding to prefeeding and three rates of response-independent food delivered during the intercomponent intervals then was compared between components. During each disruption condition, initial- and terminal-link response rates generally were more resistant in the vary component than in the repeat component. During the response-independent food conditions, terminal-link response rates were more resistant than initial-link response rates in each component, but this did not occur during prefeeding. Variation (in vary) and repetition (in repeat) both decreased during the response-independent food conditions in the respective components, but with relatively greater disruption in repeat. These results extend earlier findings demonstrating that operant variation is more resistant to disruption than is operant repetition and suggest that theories of response strength, such as behavioral momentum theory, must consider factors other than reinforcement rate. The implications of the results for understanding operant response classes are discussed.     

The ADHD Response-Inhibition Deficit as Measured by the Stop Task: Replication with DSM–IV Combined Type, Extension, and Qualification

Although response inhibition has been proposed as a core element of child attention-deficit hyperactivity disorder (ADHD), the literature is heavily reliant on studies using DSM–III–R diagnostic criteria, older methods of measuring response inhibition, samples of boys, and failing to control thoroughly for comorbid problems—both as diagnoses and as subclinical variation. The present study replicated a deficit in response inhibition in the ADHD combined type (DSM–IV, American Psychiatric Association, 1994) using samples matched on age and sex. The study replicated an effect size of approximately d = .6 in boys with ADHD, and observed an even larger effect size for girls, although the Sex × Group interaction was nonsignificant. Children with ADHD also had problems with response output, shown by variable responding. Excluding comorbid conduct disorder, reading disorder, generalized anxiety disorder, obsessive–compulsive disorder, major depression, and posttraumatic stress disorder from the sample did not alter the results. Correlations indicated that response inhibition was associated with both attentional problems and reading level. Covarying for reading problems did not eliminate the ADHD group effect, but the association of response inhibition with reading clearly requires further examination. Overall, the study supported the role of response inhibition in the DSM–IV ADHD combined type, but with key qualifications as to degree of specificity in reference both to comorbid problems and other executive functions.     

Milestones in the development of infant numeracy

This article deals with the development of numeracy among young children of the four to seven year age group. The research investigation described had two aims: to see how early numeracy develops in children of different ages; and to see whether there are fixed points which might serve as milestones in the development of infant numeracy. The results of this investigation involving 96 children indicate a strong development of numeracy skills during this period. With reference to the literature, it is also shown that certain items of a test previously developed for this purpose may be taken as core items that do indeed represent milestones in the development of infant numeracy.     

On the relation between object manipulation and stereotypic self-injurious behavior

Results from a number of studies have shown an inverse relationship between stereotypic behavior and object manipulation. The purposes of this study were to determine whether techniques similar to those used previously (prompting and reinforcement) would be effective in increasing object manipulation under both prompted and unprompted conditions, and to ascertain whether increases in object manipulation would result in decreases in stereotypic self-injurious behavior (SIB). Two individuals with developmental disabilities who engaged in SIB maintained by automatic reinforcement participated. Results showed that object manipulation increased from baseline levels when experimenters prompted participants to manipulate leisure items, but that object manipulation was not maintained under unprompted conditions, and rates of SIB stayed within baseline levels. We then attempted to increase object manipulation further by (a) reinforcing object manipulation, (b) blocking SIB while reinforcing manipulation, and (c) preventing SIB by applying protective equipment while reinforcing object manipulation. Reinforcing object manipulation alone did not affect levels of object manipulation. Blocking effectively reduced attempts to engage in SIB for 1 participant but produced no increase in object manipulation. When the 2nd participant was prevented from engaging in SIB through the use of protective equipment, rates of object manipulation increased dramatically but were not maintained when the equipment was removed. These results suggest that stimulation derived from object manipulation, even when supplemented with arbitrary reinforcement, may not compete with stimulation produced by stereotypic SIB; therefore, direct interventions to reduce SIB are required.     

When less is more: Consumer aversion to unused utility

A series of experiments demonstrates that consumers exhibit aversion to waste during forward-looking purchase. These experiments further reveal that such behavior is driven by distaste for unused utility, a reaction that is shown to be distinct from an aversion to squandering money. Waste aversion is especially pronounced when consumers anticipate future consequences and deprivation is salient. In addition to demonstrating robustness across consumers and marketing contexts, the results also demonstrate how waste aversion can lead to self-defeating behavior in which consumers forego desired utility. Finally, the present research demonstrates and discusses the implications of waste aversion for a variety of marketing issues, including buy-rent markets, bundling, and the fundamental distinction between goods and services.     

The functions of music and their relationship to music preference in India and Germany

Is the use of music in everyday life a culturally universal phenomenon? And do the functions served by music contribute to the development of music preferences regardless of the listener's cultural background? The present study explored similarities and dissimilarities in the functions of music listening and their relationship to music preferences in two countries with different cultural backgrounds: India as an example of a collectivistic society and Germany as an example of an individualistic society. Respondents were asked to what degree their favorite music serves several functions in their life. The functions were summarized in seven main groups: background entertainment, prompt for memories, diversion, emotion regulation, self‐regulation, self‐reflection, and social bonding. Results indicate a strong similarity of the functions of people's favorite music for Indian and German listeners. Among the Indians, all of the seven functions were rated as meaningful; among the Germans, this was the case for all functions except emotion regulation. However, a pronounced dissimilarity was found in the predictive power of the functions of music for the strength of music preference, which was much stronger for Germans than for Indians. In India, the functions of music most predictive for music preference were diversion, self‐reflection, and social bonding. In Germany, the most predictive functions were emotion regulation, diversion, self‐reflection, prompt for memories, and social bonding. It is concluded that potential cultural differences hardly apply to the functional use of music in everyday life, but they do so with respect to the impact of the functions on the development of music preference. The present results are consistent with the assumption that members of a collectivistic society tend to set a higher value on their social and societal integration and their connectedness to each other than do members of individualistic societies.