CONTINGENT REINFORCEMENT FOR CARBON MONOXIDE REDUCTION: WITHIN-SUBJECT EFFECTS OF PAY AMOUNT

The relationship between reinforcer amount and daytime smoking reduction in smokers offered money for reduced afternoon breath carbon monoxide (CO) levels was examined. Twenty-three hired regular smokers with average baseline CO levels of about 30 ppm were exposed in random order to five sliding scale payment schedules that changed daily or weekly. Money was available for afternoon CO readings between 0 and 21 ppm with pay amount inversely related to the absolute CO reading obtained. Maximum pay amount for readings below 7 ppm varied among $0, $1.50, $3, $6, and $12 per day. Contingent reinforcement promoted CO and daytime cigarette reduction within individuals with the amount of behavior change related to the amount of payment available. Average CO levels decreased from 30 to 15 ppm as a function of pay amount whereas self-reported daytime cigarettes decreased from 12 to 5 per day. Average minutes of cigarette abstinence prior to the afternoon study contact increased from 62 to 319 minutes as a function of pay amount, whereas the percentage of available money earned increased from 22% to 48%. Nontargeted evening cigarette use also decreased during periods of daytime smoking reduction. The orderly effects of this contingent reinforcement intervention on daytime smoking of regular smoker volunteers suggest that this is a sensitive model for continued evaluation of factors that influence smoking reduction and cessation.     

Violations of stochastic transitivity on concurrent chains: Implications for theories of choice

The concurrent-chains procedure has been used to measure how choice depends on various aspects of reinforcement, such as its delay and its magnitude. Navarick and Fantino (1972, 1974, 1975) have found that choice in this procedure can violate the condition of stochastic transitivity that is required if a unidimensional scale for reinforcements is to be possible. It is shown in this paper that two simple unidimensional models of choice on concurrent chains can produce violations of stochastic transitivity. It is argued that such violations may result from the complex contingencies of the concurrent-chains procedure.     

The effects of instructions, incentive, and feedback on a community problem: dormitory noise

A reinforcement system utilizing instructions, modelling, feedback, and group reinforcement was employed in an attempt to reduce disruptive noise on three university residence halls. A fourth hall received the same treatment program without the reinforcement component. Noise scores were determined by recording the number of discrete noise occurrences over a criterion decibel level. On all four residential floors, noise scores during treatment conditions were lower than initial and final baseline levels. Additionally, periods of noise reduction corresponded to the changing criterion multiple-baseline and reversal designs utilized. Pre- and posttreatment questionnaire responses from the three reinforcement floors paralleled changes in objective noise data. At posttreatment, residents reported less noise disturbance of study and sleep and more control over the noise situation and floor problems in general. These results indicated that a comprehensive behavior-modification treatment package was effective in reducing disruptive noise in university residence halls. Difficulties in data collection and anomalies in the data are discussed. Future directions for field-based behavior-modification research are outlined.     

四周简易正念减压训练对初中生焦虑的影响

选取68名初一学生并以班级为单位分为四周正念减压(mindfulness-based stress reduction,MBSR)训练组和对照组,探讨四周MBSR对初中生焦虑和正念水平的影响,以及训练效果是否存在基线效应与性别差异。结果发现:(1)四周MBSR可以提高初中生的正念水平,缓解其焦虑情况;(2)“不判断”和“特质焦虑”基线水平影响正念训练的效果;(3)四周MBSR对初中生的训练效果不存在性别差异。     

An evaluation of the ability to voluntarily reduce the heart rate after a month of yoga practice

The study aimed at determining whether novices to yoga would be able to reduce their heart rate voluntarily and whether the magnitude of reduction would be more after 30 days of yoga training. Two groups (yoga and control,n=12 each) were assessed on Day 1 and on Day 30. During the intervening 30 days, the yoga group received training in yoga techniques while the control group carried on with their routine. At each assessment the baseline heart rate was recorded for one minute, this was followed by a six-minute period during which participants were asked to attempt to voluntarily reduce their heart rate, using any strategy. Both the baseline heart rate and the lowest heart rate achieved voluntarily during the six-minute period were significantly lower in the yoga group on Day 30 compared to Day 1 by a group average of 10.7 beats per minute (i.e., bpm) and 6.8 bpm, respectively (p<.05, Wilcoxon paired signed ranks test). In contrast, there was no significant change in either the baseline heart rate or the lowest heart rate achieved voluntarily in the control group on Day 30 compared to Day 1. The results suggest that yoga training can enable practitioners to use their own strategies to reduce the heart rate, which has possible therapeutic applications.     

Thermodynamics: What One Needs to Know

Thermodynamics is the foundation of many of the topics of interest in the religion-science dialogue. Here a nonmathematical outline of the principles of thermodynamics is presented, providing a historical and conceptually understandable development that can serve teachers from disciplines other than physics. The contributions of Gibbs to both classical and rational thermodynamics, emphasizing the importance of the ensemble in statistical mechanics, are discussed. The seminal ideas of Boltzmann on statistical mechanics are contrasted to those of Gibbs in a discussion of the microscopic interpretation of the second law. The role of information theory is discussed, and the modern ideas of Prigogine and nonequilibrium are outlined in some detail with further reference to the second law. Implications for our interaction with God are considered.     

Cue effectiveness in communicatively efficient discourse production

Recent years have seen a surge in accounts motivated by information theory that consider language production to be partially driven by a preference for communicative efficiency. Evidence from discourse production (i.e., production beyond the sentence level) has been argued to suggest that speakers distribute information across discourse so as to hold the conditional per-word entropy associated with each word constant, which would facilitate efficient information transfer (Genzel & Charniak, 2002). This hypothesis implies that the conditional (contextualized) probabilities of linguistic units affect speakers' preferences during production. Here, we extend this work in two ways. First, we explore how preceding cues are integrated into contextualized probabilities, a question which so far has received little to no attention. Specifically, we investigate how a cue's maximal informativity about upcoming words (the cue's effectiveness) decays as a function of the cue's recency. Based on properties of linguistic discourses as well as properties of human memory, we analytically derive a model of cue effectiveness decay and evaluate it against cross-linguistic data from 12 languages. Second, we relate the information theoretic accounts of discourse production to well-established mechanistic (activation-based) accounts: We relate contextualized probability distributions over words to their relative activation in a lexical network given preceding discourse.     

Revisiting the Obama Effect: Exposure to Obama reduces implicit prejudice

The present research experimentally evaluated whether exposure to Barack Obama, a positive counter-stereotypic exemplar, can result in a decrease in implicit anti-Black prejudice among non-Black participants. In order to undo any existing influence of exposure to Obama, we first exposed some participants to negative Black exemplars. Participants were assigned to one of three conditions where they were exposed subtly to negative Black exemplars, to negative Black exemplars and then Obama, or to neutral X's (i.e., control). Participants who were only primed with negative Black exemplars showed more implicit negativity toward Black people compared to the control group. Participants exposed to the same negative Black exemplars and then Obama showed a decrease in implicit racial bias levels compared to those in the negative exemplar only condition, providing experimental evidence that exposure to Obama can decrease implicit racial bias levels. These findings indicate that even subtle exposure to a positive, counter-stereotypic exemplar can reduce implicit prejudice.     

Peer pressure against prejudice: A high school field experiment examining social network change

Individuals often conform to the intergroup attitudes and behaviors modeled by their peers in a given situation. To what extent does peer influence on intergroup prejudice 1) diffuse across a social network of peers and 2) affect attitudes and behavior across time? Student leaders (“Peer Trainers”) were trained to confront expressions of intergroup prejudice in five randomly assigned high schools across a period of five months; students recruited to be Peer Trainers in five control schools waited to be trained. Independent surveys of Peer Trainers' social networks reveal that treatment Peer Trainers were significantly more likely than control Trainers to be nominated by peers as students who confront prejudice. Treatment Peer Trainers' tolerant behavior spread to close friends and to acquaintances in their social network; their attitudes spread inconsistently, and only to close friends. Studying peer influence within social networks can improve understanding of social influence, prejudice reduction, and social change.