Pigeons can discriminate locations presented in pictures

The present experiments were designed to teach pigeons to discriminate two locations represented by color photographs. Two sets of photographs were taken at two distinctive locations on a university campus. These sets represented several standpoints at each location. For the true-discrimination group, pictures from the two locations were differentially associated with reward; for the pseudodiscrimination group, half of the views from each location were arbitrarily but consistently associated with reward. The former group acquired the discrimination much more rapidly. These birds also showed good transfer to new views from the standpoints used in training and to a new standpoint at each location not used in training. In a second experiment, another group of pigeons could terminate any training trial by pecking an “advance” key. Three of 4 subjects used this option to reduce the duration of trials in which pictures from the negative location were presented. These data suggest that pigeons can integrate views shown in pictures into a “concept” of a location. The method used here may be the experimental analogue of a common, natural process by which animals learn to identify locations.     

Parents' perceptions of the quality of infant sleep behaviours and practices: A qualitative systematic review

A systematic review of qualitative studies was conducted to explore how parents perceive sleep quality in their infants aged 0–24 months and the factors that influence these perceptions. A systematic search of the databases Scopus, Embase, Cinahl, PsycInfo and MEDLINE, was undertaken to identify eligible peer-reviewed studies published between 2006–2021. Ten papers met inclusion criteria and were subsequently included in the review. Evaluation of papers with the Critical Appraisal Skills Programme qualitative checklist classified papers as weak, moderate or strong, with half considered strong. Thematic synthesis identified one superordinate theme, culture, and five interrelated subordinate themes regarding how parents perceive their infant's sleep and the factors that may influence these perceptions. These themes were: (1) Infants physical and emotional comfort; (2) Beliefs regarding safety; (3) Parental and familial wellbeing; (4) Perceived degree of infant agency; (5) Influence of external beliefs and opinions. The findings from this review may assist practitioners in providing parents with personalized and culturally sensitive information regarding infant sleep and may also inform antenatal and early intervention practices, subsequently minimizing parental distress regarding infant sleep patterns.     

Separability of item and person parameters in response time models

This paper discusses two forms of separability of item and person parameters in the context of response time (RT) models. The first is separate sufficiency: the existence of sufficient statistics for the item (person) parameters that do not depend on the person (item) parameters. The second is ranking independence: the likelihood of the item (person) ranking with respect to RTs does not depend on the person (item) parameters. For each form a theorem stating sufficient conditions, is proved. The two forms of separability are shown to include several (special cases of) models from psychometric and biometric literature. Ranking independence imposes no restrictions on the general distribution form, but on its parametrization. An estimation procedure based upon ranks and pseudolikelihood theory is discussed, as well as the relation of ranking independence to the concept of double monotonicity.I am indebted to Wim van der Linden for bringing Thissen's (1983) paper to my notice, and to Martijn Berger, Frans Tan, and the anonymous reviewers for their constructive comments on earlier drafts of this paper.     

Risk perception and the location of a repository for spent nuclear fuel

This study investigates lay people's reactions to a repository for nuclear waste. Risk perception is seen as a complex concept, comprising both affective and cognitive components. Attitude towards nuclear power and trust in experts and authorities had a substantial impact on risk perception, while personal knowledge about nuclear waste disposal had no effect. Thus, the more positive one's attitude towards nuclear power is and the more trust one has in experts and authorities, the lower one's risk perception is. Also, reactions were expected to vary with distance between the home district and the location of a repository. These variations differed in nature for people with alternative levels of risk judgement. The distance between the home and a repository affected approval of the proposed site. Distance between home and repository also had an effect on risk feelings and somewhat less on beliefs about consequences. Estimated total risk was directly mediated by beliefs about consequences, but even more so by risk feelings. With regard to risk, one can conclude that it is important to make a distinction between an emotional and a cognitive component of risk perception.     

Formation of transitivity in conditional matching to sample by pigeons

Four homing pigeons were trained over 5 months in a zero-delay, “arbitrary” matching-to-sample procedure with sample and comparison stimuli presented on any of three response keys. Birds were also required to complete a fixed-ratio 10 requirement on both sample and comparison stimuli to terminate their presentation. The procedure resulted in the establishment of relations that were not specifically trained and that can be characterized by the property of transitivity in a stimulus equivalence context. This result was in contrast with the findings obtained from most previous research with nonhuman subjects.     

Interactions in multiple schedules: negative induction with squirrel monkeys

In Experiment I, lever pressing by squirrel monkeys was maintained under a sequence of variable-interval, multiple variable-interval variable-interval, and multiple variable-interval extinction schedules of food presentation. Negative induction (decreased responding in the unchanged component) occurred when one component of the multiple variable-interval variable-interval schedule was changed to extinction. Negative induction was transient over sessions; responding in the unchanged component usually recovered to a rate similar to that under the multiple variable-interval variable-interval schedule. Negative induction was not accompanied by consistent changes in the patterns of local responding within the unchanged component, and did not depend on whether component schedules were associated with localized (lever lights) or diffuse visual stimuli (houselights), or on whether the unchanged component was a 60- or 180-sec variable-interval schedule. In Experiment II, responding was maintained under a sequence of variable-interval and multiple variable-interval timeout schedules of food presentation. Negative induction occurred when responding declined gradually in the timeout component but not when responding declined abruptly. The nature of interactions in multiple schedules may depend on the species; negative induction was observed with squirrel monkeys under conditions similar to those that produce positive contrast with pigeons.     

Variability of response location on fixed-ratio and fixed-interval schedules of reinforcement

Variability of response location was studied in monkeys performing in a six-lever chamber. Fixed-ratio schedules, ranging from FR 1 to FR 300, generated a high degree of stereotypy of response location. In contrast, fixed-interval schedules of comparable reinforcement frequencies (0.06 to 4 minutes) generated much greater variability. These results failed to confirm any simple relationship between response variability and intermittence of reinforcement. Rather, variability seems to be determined by the particular characteristics of the reinforcement schedule.     

自我同情和睡眠质量的关系：积极和消极情绪与自我控制的中介作用

为探究积极和消极情绪与自我控制在自我同情与睡眠质量间的中介机制,采用问卷法对477名成人进行调查,建立结构方程模型对中介效应进行检验。结果发现：（1）自我同情、积极情绪、自我控制和睡眠质量两两之间均为显著正相关,而上述变量与消极情绪均为显著负相关;（2）自我同情可分别以积极情绪、消极情绪和自我控制为中介来预测睡眠质量;还可依靠消极情绪与自我控制的链式中介效应来间接预测睡眠质量,但自我同情对睡眠质量的直接效应不显著。该研究结果为改善睡眠质量提供了新的干预视角。