Do rats like to work for their food?

Rats were given a choice in a two-compartment box between response-dependent and response-independent schedules of food presentation. In general, the response-independent schedule was preferred, but the preference was not exclusive and considerable amounts of time were spent on the “work” (response-dependent) side. Food deprivation caused an increased preference for the response-independent schedule when the schedules were fixed, but not when they were variable. Addition of a signal to the work side, indicating the availability of reinforcement, increased preference for that side. In general, the relative numbers of reinforcements obtained on the response-independent side exceeded the relative time spent there; when the relative reinforcements were equated by adding delays to the response-independent side, indifference between the schedules resulted. Latencies of food collection were higher on the response-independent side than on the lever side, and it is suggested that this gives a clue to the factors maintaining “work” in this situation.     

A comparison of two estimation algorithms for Samejima’s continuous IRT model

This study compares two algorithms, as implemented in two different computer softwares, that have appeared in the literature for estimating item parameters of Samejima’s continuous response model (CRM) in a simulation environment. In addition to the simulation study, a real-data illustration is provided, and CRM is used as a potential psychometric tool for analyzing measurement outcomes in the context of curriculum-based measurement (CBM) in the field of education. The results indicate that a simplified expectation-maximization (EM) algorithm is as effective and efficient as the traditional EM algorithm for estimating the CRM item parameters. The results also show promise for using this psychometric model to analyze CBM outcomes, although more research is needed in order to recommend CRM as a standard practice in the CBM context.     

Superassertibility and the Equivalence Schema: A Dilemma for Wright’s Antirealist

Crispin Wright champions the notion of superassertibility as providing a truth predicate that is congenial to antirealists in many debates in that it satisfies relevant platitudes concerning truth and does so in a very minimal way. He motivates such a claim by arguing that superassertibility can satisfy the equivalence schema: it is superassertible that P if and only if P. I argue that Wright’s attempted proof that superassertibility can satisfy this schema is unsuccessful, because it requires a premise that has not been properly motivated and is prima facie implausible. I further argue that, even if the dubious premise is accepted, the resulting proof is intuitionistically invalid. This is problematic, because a proponent of superassertibility as a truth predicate has independent reasons to affect a logical revision in the direction of intuitionism. The resulting dilemma suggests that superassertibility may not be an adequate truth candidate for any significant ranges of discourse. Cambridge, MA: Harvard University Press, 1992     

Using a runway paradigm to assess the relative strength of rats’ motivations for enrichment objects

Laboratory animals should be provided with enrichment objects in their cages; however, it is first necessary to test whether the proposed enrichment objects provide benefits that increase the animals’ welfare. The two main paradigms currently used to assess proposed enrichment objects are the choice test, which is limited to determining relative frequency of choice, and consumer demand studies, which can indicate the strength of a preference but are complex to design. Here, we propose a third methodology: a runway paradigm, which can be used to assess the strength of an animal’s motivation for enrichment objects, is simpler to use than consumer demand studies, and is faster to complete than typical choice tests. Time spent with objects in a standard choice test was used to rank several enrichment objects in order to compare with the ranking found in our runway paradigm. The rats ran significantly more times, ran faster, and interacted longer with objects with which they had previously spent the most time. It was concluded that this simple methodology is suitable for measuring rats’ motivation to reach enrichment objects. This can be used to assess the preference for different types of enrichment objects or to measure reward system processes.     

Rats respond for food in the presence of free food: How free is the “free” food?

An experiment conducted by A.J. Neuringer (Science, 1969,166, 399–401) in which he reported that rats maintained appreciable levels of bar pressing for earned food in the presence of freely available food was critically examined and replicated. Rats were trained to bar press, then housed in operant chambers and administered a 15-day preference test between free and earned food, followed successively by 10 days of free food only, a second 6-day preference test, and 7 days of earned food only. Throughout the experiment half of the animals were provided with tall free-food containers similar to those used by Neuringer; the other half were provided with short containers similar to those more commonly employed by other researchers. The former animals showed a consistent propensity to bar press for earned food across both preference tests, while the latter animals showed only an initial propensity to bar press which subsequently declined to very low levels. These results indicate that the maintenance of significant amounts of bar pressing by the rats in Neuringer's report was due to the relatively more effortful free-food source he employed. The utility of a neophobia-optimality model in explaining the present data is discussed.     

A Peircean examination of Gettier’s two cases

If we accept certain Peircean commitments, Gettier’s two cases are not cases of justified true belief because the beliefs are not true. On the Peircean view, propositions are sign substitutes, or “representamens.” In typical cases of thought about the world, propositions represent facts. In each of Gettier’s examples, we have a case in which a person S believes some proposition p, there is some fact F* such that were p to represent F* to S then p would be true, and yet p does not represent F* to S but some other fact F of which p is false. Since truth is a property of propositions with respect to their representational function, it follows that the belief is not true. Although an examination of Gettier’s two cases, this essay is not a defense of the justified true belief (JTB) analysis of knowledge, for there are objections to the JTB analysis other than Gettier’s two cases. Rather, Gettier’s two cases are of particular interest for the light they shed on the nature of truth and representation.

     

The Effects of a Can’t-Answer Response Option and Instructions on Stimulus Equivalence

The Psychological Record - Two interlocking conditional discriminations were established in a paper-and-pencil match-to-sample format by written rule-like instructions to 104 college...     

Parents’ experiences of family food routines in adolescent elite-level swimming

ObjectiveParents have an important role in their child’s food routines and eating behaviour and face additional demands when that child is an athlete. Yet little is known about how parents manage providing food for their athletic child, in addition to the wider family, within the context of elite-level youth sport.MethodsSemi-structured interviews were conducted with sixteen parents (mothers = 11; fathers = 5) of elite level adolescent swimmers (i.e., competing at UK national level or above; child mean age = 15.4 years) to explore their experiences of family food routines and eating behaviour. Reflexive Thematic Analysis was used to analyse the data.ResultsParents outlined the importance of ‘optimal’ fuelling for their athletic child. Parents had an active role in their child’s eating behaviour and shaping their food choices but expressed uncertainty regarding the volume of food their child should consume and concerns regarding their child’s future relationship with food. Meticulous organisational and logistical strategies were employed to meet the extensive food requirements of their adolescent elite swimmer in the face of intensive training schedules. Such schedules also impacted food routines for the wider family (i.e., fewer family mealtimes), and on the quality of parents’ own diets.ConclusionThe findings highlight that clearer guidance is needed for parents of elite adolescent swimmers in relation to quantities of food intake and how to support a positive future relationship with food (specifically during any periods of transition in their training or out of the sport). The findings also identify a novel organisational stressor for parents in elite youth sport, in managing and prioritising their own diet. Further research is needed to explore the extent to which parental diet may be impacted by supporting an adolescent athlete.     

Imitation of mother’s inappropriate food preference in weanling kittens

Experiments were performed on four mother cats and their 22 kittens from 7 litters. Each mother was trained to eat banana or mashed potato in the presence of meat pellets in order to get a hypothalamic stimulation reward. Eighteen of twenty-two weanling kittens which accompanied the mother during the session imitated the mother in eating banana or potato and ignored meat pellets. The imitation of the mother started not earlier than at 35 days of age and in most kittens (10 of 18) began between 49 and 56 days of age. The kittens which ate banana or potato with the mother also ate that food when tested alone after weaning at 9 to 27 weeks of age, either during 10 min sessions in the experimental compartment or during 24 hr tests in the home compartment. When banana was offered to 9 control 13–23 week old kittens (of three other mothers) who never before had eaten that food or had seen their mother eat it, 8 of them did not consume banana during three 24 hr tests. Some consumption, however, occurred in the ninth kitten during the third of these tests. It has been concluded that weanling kittens in the period of transition from maternal to independent feeding tend to imitate the mother in food preferences, even if the food chosen by the mother is unusual for their species. The food preferences acquired through the imitation of the mother may influence the food preferences at the later stages of life.     

A method for automatically recording topographical differences in pigeons’ keypecking for food and water reinforcers

The topography of pigeons’ keypecking responses for food reinforcers is visibly different from the keypeck topography for water reinforcers. Previous methods of recording topographies have been complex and not without problems. A simple inexpensive modification of a standard pecking key permits the recording of two components of the topography in sufficient detail to allow the detection of these topographical differences.     

Floating food: Eating ‘Asia’ in kitchens of the diaspora

This article borrows fragments of memory to chart a drifting course towards an imagined ‘other’ of ‘Asia’, produced and consumed in the kitchens of the west and available for diasporic digestion. Specifically, the argument focuses on micro-narratives of ‘Asian’ food, with these emerging here during an interview on food and transnationalism, conducted while the interviewer and household members eat together in the intimacy of a North London kitchen. Specifically, the analysis reflects on these narratives, tracing some of their curious and disturbing nuances. The ‘oddness’ of such stories (identity's capacity to ‘float’ while ‘grounded’), in turn, is used to question the figure of the consuming cosmopolitan (and its necessary ‘other’) that haunts cultural and culinary analyses. Meanwhile, everyday practices of ‘eating back’ at ‘Asia’ in order to feel ‘at home’ become resonant resources not only for identity's place-making but also for imagining a different politics of eating. Furthermore, the narrative richness of everyday interactions between strangers and familiars in the kitchen points to less usual, and perhaps more productive, ways of understanding the complexities of diasporic place-making.     

Women’s regulation styles for eating behaviors and outcomes: The mediating role of approach and avoidance food planning

The purpose of this article was to examine the role played by different orientations in planning for eating behaviors as mediators of the relationship between regulation styles and eating behaviors. In Study 1, a new scale was developed to assess approach food planning and avoidance food planning. Results from confirmatory analyses (N = 241) supported the two-factor structure of the scale. In Study 2 (N = 202), in agreement with past research on the effects of autonomous and controlled motivation for the regulation of eating behaviors, we found that approach food planning partially mediated the effects of autonomous regulation for eating behaviors on healthy eating behaviors, while avoidance food planning partially mediated the effects of controlled regulation for eating behaviors on dysfunctional eating behaviors. Implications of these results for self-determination theory and for promoting healthy eating behaviors are discussed.

Measuring Adolescents’ Affective Civic Competence: Validity and Cross-Group Equivalence of a Second-Order Hierarchical Latent Construct

Applied Research in Quality of Life - In the last few decades, educational literature and policy makers have increasingly supported research into affective competencies—attitudes, emotions,...     

The effect of reading ‘List’ and ‘Overview’ summaries on the recall of two narrative texts

This paper reports an investigation of the mnemonic value of reading a summary before a text. Subjects (194 sixth-form students) read one of two folk-tales, either in isolation or preceded by a ‘List’ or an ‘Overview’ type of summary. Free recall of the story was then tested. Overall, both types of summary produced a significant increase in recall, although further analyses showed that their effects were located primarily in the recall of the latter parts of the stories. It is suggested that future work could usefully extend the analysis to a consideration of longer, and less well structured texts.