Uninstructed human responding: sensitivity to ratio and interval contingencies

College students' presses on a telegraph key were occasionally reinforced by light onsets in the presence of which button presses (consummatory responses) produced points later exchangeable for money. One student's key presses were reinforced according to a variable-ratio schedule; key presses of another student in a separate room were reinforced according to a variable-interval schedule yoked to the interreinforcement intervals produced by the first student. Instructions described the operation of the reinforcement button, but did not mention the telegraph key; instead, key pressing was established by shaping. Performances were comparable to those of infrahuman organisms: variable-ratio key-pressing rates were higher than yoked variable-interval rates. With some yoked pairs, schedule effects occurred so rapidly that rate reversals produced by schedule reversals were demonstrable within one session. But sensitivity to these contingencies was not reliably obtained with other pairs for whom an experimenter demonstrated key pressing or for whom the reinforcer included automatic point deliveries instead of points produced by button presses. A second experiment with uninstructed responding demonstrated sensitivity to fixed-interval contingencies. These findings clarify prior failures to demonstrate human sensitivity to schedule contingencies: human responding is maximally sensitive to these contingencies when instructions are minimized and the reinforcer requires a consummatory response.     

Evaluating the evaluator: The effects of the valence,sequence and target of evaluations on the perception of the evaluator

People commonly want to be perceived as intelligent, as well as be liked by others. Previous research has demonstrated that people who wish to appear intelligent tend to criticise others, and that criticising others indeed leads to the perception of high intelligence. In the current research we hypothesised and found that this is not the case when (a) the criticism is targeted towards the people who form the impression, and (b) the criticism is targeted towards those with whom the people who form the impression have just interacted. In both cases, participants in our study liked evaluators less when they used criticism than when they used praise. Moreover, they perceived the evaluators as less intelligent. We also demonstrated that in cases of mixing praise with criticism, the sequence of the evaluation interacted with the target of the evaluation in influencing liking. We found a greater liking for evaluators whose evaluation changed from negative to positive rather than vice versa, but only when the perceiver was the target of the evaluation. The discussion centres on the potential underlying mechanisms for these results, as well as on the practical applications of the results and directions for future research.     

Comparison of prompting procedures to teach internet skills to older adults

The Internet and information and communications technologies (ICTs) have been found to produce meaningful social interactions and greater social support among older adults (White et al., 2002 ). Despite these benefits, the Internet and ICTs are not widely used among the older‐adult population (Cresci, Yarandi, & Morrell, 2010 ). The purpose of the current study was to compare the effectiveness and efficiency of video prompting and text‐based instructions on the acquisition of three tablet‐based tasks: emailing, video calling (FaceTime® application), and searching for a YouTube? video. Both video prompting and text‐based instructions were effective for all three participants, with text‐based instructions being slightly more efficient for one participant and video prompting being more efficient for two participants, suggesting that both prompting procedures can be used to teach older adults Internet and ICT skills.     

Comparing self‐directed methods for training staff to create graphs using Graphpad Prism

An important skill for behavior analysts is creating graphs that clearly convey outcomes and conform to publication conventions. GraphPad Prism is software designed for creating scientific graphs, but no prior research has empirically evaluated training graphing skills using Prism. Two effective training methods are enhanced written instructions (EWI) and video modeling with voiceover instructions (VMVO), but no single‐subject studies have compared the effects of these methods. In this study, we compared the efficacy and social validity of EWI and VMVO for training staff to create graphs using Prism. A single‐subject design was employed to compare the effects of the methods on the individual performance of 11 graduate students. EWI and VMVO were both found to be effective, and more participants chose to use EWI.     

“要有创造性”指导语效应及其对创造性教学的启示

“要有创造性”指导语效应（effects of explicit instructions to“be creative”）,是指在创造力测验或实验任务中,明确要求“要有创造性”（be creative）的指导语,能够促进被试的创造性表现的现象。该效应的理论解释主要有最大化表现理论、目标设置理论和注意控制理论。在指导语中对“创造性”作出解释、创造性任务的类型以及被试特征,都会影响“要有创造性”指导语效应的产生。在创造性教学过程中,可以根据“要有创造性”指导语效应发生的机制,从设置创造性目标、根据任务特征施加精细指导、结合学生特征实施个性化教学三个方面,设计创造性活动,以促进学生创新能力的发展。     

Perception of speech reflects optimal use of probabilistic speech cues

Listeners are exquisitely sensitive to fine-grained acoustic detail within phonetic categories for sounds and words. Here we show that this sensitivity is optimal given the probabilistic nature of speech cues. We manipulated the probability distribution of one probabilistic cue, voice onset time (VOT), which differentiates word initial labial stops in English (e.g., "beach" and "peach"). Participants categorized words from distributions of VOT with wide or narrow variances. Uncertainty about word identity was measured by four-alternative forced-choice judgments and by the probability of looks to pictures. Both measures closely reflected the posterior probability of the word given the likelihood distributions of VOT, suggesting that listeners are sensitive to these distributions.     

Observer Influences on Fathers and Mothers: An Experimental Manipulation of the Structure and Function of Parent – Infant Conversation

From studies over the past 20 years four contrasting hypotheses can be made about the nature of parent–infant communication: (1) mothers and fathers display similar skills to their infants and do not exert a differential influence on their development; (2) fathers are less sympathetic to their infants' level of development and therefore inadvertently stretch the child's development more than mothers; (3) both parents differentially socialize their sons' and daughters' early communicative skills; (4) any apparent differences between parents reflect their expectations about being observed. To examine these hypotheses together, this experiment records the communication of 10 mother–infant and 10 father–infant dyads in two conditions: when an observer was present or absent. The analysis revealed two patterns. Firstly, in keeping with most research on parent–child communication, mothers and fathers both simplified their speech to their infants in similar ways. Secondly, both the structure and function of parental communication showed differences between the two conditions and many of these differences were moderated by interactions between condition and sex of parent or child. The data thus provide more support for the first and fourth hypotheses cited above. It is suggested that analyses of parent–infant interaction should move away from simple assumptions about parental ‘influences’ upon children's development to consider the subtleties of different parental styles in different settings.     

Comparing detailed and less detailed pre-lineup instructions

It is generally agreed that proper pre-lineup instructions can reduce the rate of mistaken identifications of innocent suspects. However, the exact nature of these instructions has not been empirically established. We compared the effects of the detailed pre-lineup instructions recommended by the US Department of Justice to a simple instruction that the perpetrator may or may not be present. Both forms of unbiased instructions significantly reduced mistaken identifications when compared with biased instructions. Comparison of performance using the utility-based analysis deviation from perfect performance demonstrated that unbiased instructions are to be preferred under assumptions of low base rates or high costs of mistaken identifications and do as well as biased instructions under assumptions of high base rates or low cost of misidentification.     

Refining the blank line-up procedure: How should we instruct eyewitnesses?

Presenting a blank line-up—containing only fillers—to witnesses prior to showing a real line-up might be useful for screening out those who pick from the blank line-up as unreliable witnesses. We show that the effectiveness of this procedure varies depending on instructions given to witnesses. Participants (N = 462) viewed a simulated crime and attempted to identify the perpetrator from a line-up approximately 1 week later. Rejecting a blank line-up was associated with greater identification accuracy and greater diagnosticity of suspect identifications, but only when witnesses were instructed prior to the blank line-up that they would view a series of line-ups; the procedure was ineffective for screening when witnesses were advised they would view two line-ups or received no instruction. These results highlight the importance of instructions used in the blank line-up procedure, and the need for better understanding of how to interpret choosing patterns in this paradigm.