Food and amphetamine self-administration by baboons: effects of alternatives.

The effects of the availability of an alternative reinforcer on responding maintained by food pellets or fluid solutions were examined in 6 adult male baboons (Papio cynocephalus anubis). During daily 23-hr experimental sessions, baboons had concurrent access to both food pellets and fluid, with responding maintained under fixed-ratio schedules of reinforcement that varied between the two commodities. The fixed-ratio requirement, or cost, for pellets was increased when (a) no fluid, (b) a dilute dextrose vehicle, (c) 0.002 mg/kg d-amphetamine, or (d) 0.004 mg/kg d-amphetamine was available. When given nonrestricted concurrent access to food pellets and amphetamine at minimal cost (FR 2), baboons self-administered sufficient amphetamine to decrease pellet intake. Increasing the response requirement for pellets decreased pellet intake at a similar rate regardless of the available fluid and increased fluid intake in a variable manner among baboons such that there were no statistically significant increases in fluid intake. In contrast, when access to pellets was restricted to 70% of maximal intake under nonrestricted conditions, increasing pellet cost decreased pellet intake and increased fluid intake more rapidly when the high amphetamine dose was available. Thus, amphetamine was more effective as an economic substitute for pellets when access to pellets was restricted. The response cost for vehicle and both amphetamine concentrations was increased when baboons had nonrestricted and restricted access to pellets. Increasing the response requirement for fluid delivery decreased intake of all three fluids similarly under both pellet-access conditions. The results indicate that substitution between commodities with minimal commonalities can be studied under controlled laboratory conditions and is dependent upon reinforcement schedule and commodity restrictions.     

The Development of the Toddler Behavior Screening Inventory

The purpose of the present study was to develop the Toddler Behavior Screening Inventory (TBSI) for rapidly assessing maternal reports of toddler behavior problems. The TBSI is a 40-item measure intended for use by pediatricians, psychologists, and other child-care professionals. A group of mothers (n = 312) rated the initial 93-item TBSI in terms of behavior frequency and parental perception of the behavior as problematic. Following item elimination, 40 items were retained due to being both frequent and problematic at all toddler age levels. Data were obtained with a new sample of mothers (n = 581) and showed the TBSI to possess good reliability and validity.     

医学伦理学概念之探究

医学伦理学的概念看起来很简单,一般情况下人们便习以为常地接受了作为应用规范伦理学的一个分支的科学地位,而忽视了医学对医学伦理学所起的作用。本文认为：医学伦理学的具体内容是医学科技与伦理道德两因素相互作用的产物,对其相互作用的形式和产物的具体分析和总结便可构成这门学科的理论体系。     

Data Smoothing: Prediction of Human Behavior, Detection of Behavioral Patterns, and Monitoring Treatment Effectiveness in Single-Subject Behavioral Studies

Data-smoothing can be particularly useful in predicting human behavior, detecting behavioral patterns, and monitoring treatment effectiveness in highly variable single-subject behavioral experiments that cannot be determined by only visual inspection of their graphs. Using an example from the applied behavior analytic literature, the use of moving-average and exponential data-smoothing aided the detection of the unique behavioral patterns of a child with autism across different treatments. Furthermore, the utility of the data-smoothing procedures to monitor and control the effectiveness of an intervention is discussed. The ease of their calculations suggest use of data-smoothing by behavior analysts whenever the effects of particular interventions are questionable.     

Should the behavioral sciences become more pragmatic? The case for functional contextualism in research on human behavior

Although societal need for behavioral science research is enormous, current research practices seem to be inefficient vehicles for producing knowledge that guides practical action. Many of our most popular theories provide little direct guidance for application. They focus on the development of models of the relationships among organismic events such as attitudes, self-efficacy expectations, and behavior, but pay little or no attention to the contextual influences on behavior. Such research is in keeping with a long-standing mechanistic tradition in psychology. We propose a version of contextualism as an alternative paradigm for the behavioral sciences. According to this paradigm, theories and research are evaluated in terms of their contribution to the prediction and influence of behavior. Basic research organized to pursue this goal has a direct bearing on how behavioral phenomena can be changed for practical purposes. Conversely, applied research contributes to basic understanding of the determinants of psychological phenomena.     

EMERGENCE OF REINFORCER PREFERENCE AS A FUNCTION OF SCHEDULE REQUIREMENTS AND STIMULUS SIMILARITY

Tustin (1994) recently observed that an individual's preference for one of two concurrently available reinforcers under low schedule requirements (concurrent fixed-ratio [FR] 1) switched to the other reinforcer when the schedule requirements were high (concurrent FR 10). We extended this line of research by examining preference for similar and dissimilar reinforcers (i.e., those affecting the same sensory modality and those affecting different sensory modalities). Two individuals with developmental disabilities were exposed to an arrangement in which pressing two different panels produced two different reinforcers according to progressively increasing, concurrent-ratio schedules. When two dissimilar stimuli were concurrently available (food and a leisure item), no clear preference for one item over the other was observed, regardless of the FR schedules in effect (FR 1, 2, 5, 10, and 20). By contrast, when two similar stimuli were concurrently available (two food items), a clear preference for one item emerged as the schedule requirements were increased from FR 1 to FR 5 or FR 10. These results are discussed in terms of implications for conducting preference assessments and for selecting reinforcers to be used under training conditions in which response requirements are relatively high or effortful.     

Courteous service: Its assessment and modification in a human service organization

We evaluated strategies to increase behaviors associated with courteous provision of service by 3 staff members of a human service agency. Training included written instructions, practice, and performance feedback. A lottery procedure was introduced to maintain courteous service after training. The results of a multiple baseline design across the 3 participants showed marked increases in courteous behaviors following training. These effects were maintained at 3-, 5-, and 8-month follow-ups. Consumers' satisfaction with service also increased. These findings suggest that simple training and reinforcement procedures can enhance courtesy afforded those who receive service from public and nonprofit organizations.     

ANALYSIS OF A HIGH-PROBABILITY INSTRUCTIONAL SEQUENCE AND TIME-OUT IN THE TREATMENT OF CHILD NONCOMPLIANCE

This study evaluated the effectiveness of high-probability requests and time-out as treatments for noncompliance that appeared to be maintained by contingent attention in 2 developmental normal children. The introduction of high-probability requests increased compliance for 1 child but not the other. Time-out was effective with both children, and improvements in compliance were maintained at an 8-week follow-up.     

CLASSWIDE PEER TUTORING: AN INTEGRATION STRATEGY TO IMPROVE READING SKILLS AND PROMOTE PEER INTERACTIONS AMONG STUDENTS WITH AUTISM AND GENERAL EDUCATION PEERS

A multiple baseline design across subjects with a reversal was used to examine the effects of classwide peer tutoring relative to traditional reading instruction on reading skills and social interaction time for 3 high-functioning students with autism and their typical peers in integrated, general education classrooms. Traditional reading instruction consisted largely of teacher-led instruction with individual student participation and seat work. Classwide peer tutoring consisted of 25 to 30 min of well-specified instruction in which tutor—learner pairs worked together on a classwide basis on reading fluency and comprehension skills. All students participated in 15- to 20-min unstructured free-time activities immediately following reading instruction. Results of reading assessments demonstrated that classwide peer tutoring increased reading fluency and correct responses to reading comprehension questions for students with autism and their peers. The procedure further increased the total duration of free-time social interactions for students with autism and typical peers, with individual variation in performance.     

EFFECTS OF HIGH-PROBABILITY REQUESTS ON THE SOCIAL INTERACTIONS OF YOUNG CHILDREN WITH SEVERE DISABILITIES

High-probability requests were used to increase social interactions in 3 young boys with severe disabilities who had been identified as severely socially withdrawn. A multiple baseline design across participants was used to evaluate the effects of high-probability request intervention on (a) social initiations, (b) social responses, (c) continued interactions, and (d) performance of high- and low-probability requests. The students were observed in a second setting to examine generalization effects across peers who did not participate in the training sequence and settings. The results demonstrated that the high-probability requests increased the students' responsiveness to low-probability requests to initiate social behavior. Increases were also found in (a) unprompted initiations and extended interactions to the training peers, (b) unprompted initiations and extended interactions to peers who were not involved in the training procedure, and (c) generalized unprompted initiations and interactions in a second nontraining setting. The students maintained increased levels of initiations and interactions after all prompts were removed from both the training and nontraining settings.