Maze patrolling by rats with and without food reward

The effects of food reward on rats’ behavior in radial and Dashiell tunnel mazes were examined in two experiments. In the first, with animals at ad-lib body weights, food reward reduced speed of movement at the food locations, but did not affect the patterns of movement in either maze. Exploratory efficiency in the Dashiell maze was unaffected by food reward, and spontaneous patrolling of the radial maze by the nonrewarded animals was comparable to the behavior, reported by others, of rats running for food reward on elevated eight-arm mazes. In the second experiment, with subjects maintained at 80% of ad-lib body weights, there was some evidence for “winstay” learning: food-rewarded rats in the Dashiell maze were relatively more active near the food locations than were the nonrewarded animals, and more rewarded than nonrewarded rats revisited all food locations in the radial maze. Nonetheless, exploratory efficiency in the Dashiell maze was unaffected by food reward, as was patrolling efficiency in the radial maze, which was again comparable to that of rats on elevated mazes. The similarity in behavior of rewarded and nonrewarded animals in these mazes implies that the major determinant of their behavior, whether or not food reward is provided, is a spontaneous tendency to avoid places recently visited.     

A test of the conservation model for autoshaped leverpressing and polydipsia in the rat

This study examined a conservation model (Allison & Mack, 1982) that predicts a linear relation between the weighted sum of two responses, autoshaped leverpressing and polydipsia, and the amount of food delivered on a variable-time schedule. Fifteen rats were assigned randomly to one of three groups. The rats in Group 1 were maintained at 80% of their free-feeding body weights. Those in Group 2 began at 100% but were allowed to lose weight during the experiment. The rats in Group 3 also began at 100% of their free-feeding weights and were maintained at this level. Each group was exposed to five conditions that delivered less food than that consumed during baseline and to one condition that delivered more food. The results did not support the conservation model. Contrary to the model, the decreasing linear relation between the individual responses, or the weighted sum of the responses, and the amount of food delivered was not found for all rats, and some rats responded more when an excessive amount of food was presented than during baseline.     

Temporal patterns of schedule-induced drinking and pawgrooming in rats exposed to periodic food

Five rats were exposed to fixed-time food schedules, ranging from 30 to 480 sec. Three rats displayed a postfood pattern of schedule-induced drinking, with short latencies from food delivery to drinking at all interfood interval durations. In contrast, drinking for the other 2 subjects tended to occur at lower overall levels, and drinking bouts frequently began in the middle of the interfood interval, such that the latency from food delivery to drinking increased dramatically as the interfood interval increased. Observation of these 2 subjects revealed that another form of licking-pawgrooming-occurred reliably after food delivery and before drinking bouts. A between subject comparison of the 3 postfood drinkers and the 2 pawgroomers revealed that, in addition to a common topography (repetitive licking), pawgrooming and drinking were similar with respect to their temporal locus, relation to the interfood interval, and extinction baseline levels. These similarities suggest that drinking and pawgrooming are induced by a common mechanism. Cohen, Looney, Campagnoni, and Lawler’s (1985) two-state model of reinforcer-induced motivation provides a useful framework for the interpretation of these results.     

Stimuli associated with the cancellation of food and its cues enhance eating but display negative incentive value

Initially neutral conditioned stimuli paired with food often acquire motivating properties, including serving as secondary reinforcers, enhancing instrumental responding in Pavlovian-instrumental transfer procedures, and potentiating food consumption under conditions of food satiation. Interestingly, cues associated with the cancellation of food and food cues may also potentiate food consumption (e.g., Galarce and Holland, 2009), despite their apparent negative correlations with food delivery. In three experiments with rats, we investigated conditions under which potentiation of feeding by such “interruption stimuIi” (ISs) develops, and some aspects of the content of that learning. Although in all three experiments ISs enhanced food consumption beyond control levels, they were found to act as conditioned inhibitors for anticipatory food cup entry (Experiment 1), to serve as conditioned punishers of instrumental responding (Experiment 2), and to suppress instrumental lever press responding in a Pavlovian instrumental transfer procedure (Experiment 3). Furthermore, when given concurrent choice between different foods, an IS enhanced consumption of the food whose interruption it had previously signaled, but when given a choice between performing two instrumental responses, the IS shifted rats’ choice away from the response that had previously yielded the food whose interruption had been signaled by IS (Experiment 3). Thus, the effects of an IS on appetitive responses were opposite to its effects on consummatory responding. Implications for our understanding of learned incentive motivation and the control of overeating are discussed.     

Schedule-induced wood-chewing in rats and its dependence on body weight

In Experiment 1, 12 rats were exposed to an FT 60 schedule of food reinforcement, followed either by extinction or by a massed-food control condition, in the presence of a wood block. In 9 rats, wood-chewing behavior increased systematically during the FT 60 condition and declined again during extinction or massed food, while the other 3 rats showed virtually no chewing behavior at any stage of the experiment. In Experiment 2, frequency and bout duration of wood-chewing under an FT 60 schedule of food reinforcement declined as body weight increased, in 7 rats. We conclude that wood-chewing qualifies as a schedule-induced behavior, and that it resembles schedule-induced drinking in its dependence on body weight. Unlike drinking, however, induced chewing occupied the middle region of the 60-sec interreinforcement interval, declined markedly within the session, and showed considerable within- and between-subject variability.     

Schedule-induced behavior in rats: Pellets versus powder

Food-deprived rats develop polydipsia on an intermittent schedule (fixed time 60 sec) of food pellet delivery, but not on an identical schedule of food powder delivery. This result was demonstrated with separate groups receiving each type of food and was replicated using rats as their own controls. Powdered food not only prevented the development of polydipsia, but it abruptly terminated ongoing polydipsia in rats that were switched from the scheduled delivery of pellets to powder. Ethological analysis of the behavior showed that the rats receiving powder were not engaging excessively in some behavior other than drinking. After discounting several factors, we concluded that the amount of oral activity associated with feeding, which occurred immediately after food delivery, was reciprocally related to the level of drinking.     

An opponent-process interpretation of postshock bursts in appetitive responding

While eight food-deprived rats pressed a lever for food during daily 1-h sessions, four CS-Shock₂ trials were presented. Trials were preceded by either a Shock₁ of .25, .50, .75 mA or no Shock₁. It was found that the rate of appetitive responding during the CS was greater on Shock₁-CS-Shock₂ trials relative to CS-Shock₂ trials. The data indicate that the phenomenon of postshock bursts in responding can occur in the absence of a signal for safety after shock. The results conform to the predictions of the opponent-process theory of motivation.     

The preference of rats for free or response-produced food

Three experiments were performed to investigate the preference of rats for either free or response-produced food. Rats were trained to free feed in an operant chamber and then to leverpress for food. Subsequently, they were given a choice between continuing to leverpress for food on CRF, FR 2, and FR 10 schedules or free feeding. In three experiments the independent variable was the method of free-food presentation: A fixed free-food dish was used in the first experiment, a movable dish in the second, and a large flat dish in the third experiment. The results of the three experiments were very similar, with most of the rats showing a preference for the free food. This preference increased further when more than one response was required to produce a food pellet. These results contradict any conclusion that rats have a generalized tendency to prefer response-produced to free food but provide no answer to the question of why rats do on occasion respond for food in the presence of free food.     

Learning through Teaching: Challenges and Opportunities in Facilitating Student Learning in Food Science and Nutrition by Using the Interteaching Approach

ABSTRACT: Interteaching is a new pedagogical strategy for classroom instruction that demonstrates great effective student learning outcomes in the field of psychology. It is a 20 to 30 min student‐to‐student discussion addressing the main points in a specified body of reading materials. Interteaching includes elements such as reciprocal peer tutoring, cooperative learning, and problem‐based learning. These elements have been well theorized and their effectiveness has been empirically documented. To date, little is known about the effects of interteaching on students' perceived learning outcomes in food science and nutrition. This case study describes how the interteach method was employed in an undergraduate nutrition and food science course with specific examples of the tools used, such as interteach preparation guides, the interteach record form, and the peer assessment form. Based on the continuous feedback provided by the students during the course work, several specific modifications were made from the conventional interteaching methods, including 4‐person interteaching instead of one‐on‐one interteaching, as well as the use of in‐class thought‐provoking “synthesis” questions. At the end of the course, we assessed the students' perceptions of interteaching, as well as the students' perceived learning outcomes. The method generally fostered critical thinking and enhanced their motivation, which led to their perceived learning. On the other hand, some of the students expressed challenges in learning from peers due to their peers' varied preparation levels, as well as tackling complex scientific concepts prior to lectures. Further investigation is needed to develop possible strategies for accommodating the challenges among students with different learning styles.     

Motivation,Confidence, and Control; Unraveling Active Learning for Nutrition and Food Undergraduates

Abstract: Nutrition and food students at Sheffield Hallam University completed an “active learning” assessment as part of a final year module, Applied Nutrition 2. The purpose of the “active learning” assessment was to encourage and enhance learner autonomy. The assessment consisted of 5 main stages: a briefing, thought shower, oral business proposal presentation, a feedback stage, and Nutrition Fair. To assess learner autonomy, levels of motivation, confidence, and control were quantitatively and qualitatively monitored throughout the learning journey. The results showed that levels of confidence, motivation, and control increased following each stage and significantly across the learning journey. However, there were significant gender differences in terms of achievement of marks and in levels of motivation at various stages. On average, females achieved higher marks in certain assessments and they demonstrated higher levels of motivation after the initial briefing. Further, significant differences were also reported between different degree routes in terms of achievement of marks and levels of confidence, motivation, and control. “Active learning” has been shown to foster improved levels of confidence, motivation, and control in a cohort of nutrition and food students, contributing to overall learner autonomy. Graduates able to demonstrate such qualities will undoubtedly be welcomed by employers in the relevant sectors.     

论小学生学习动机的激发

小学教师在课堂教学中过分注重知识的授受,忽视了小学生的主体性。据此提出在课堂教学中教师要接受小学生的情绪,融入小学生的世界;优化教学,是教师激发小学生学习动机的主阵地;运用强化原理,有助于激发小学生的学习动机,并起到巩固学习效果的作用。     

Social transmission of food preferences among norway rats by marking of food sites and by gustatory contact

Three experiments were conducted to investigate the social learning and transmission of food preferences by excretory marking among adult male Norway rats. The experiments extend our earlier findings that rats prefer to eat from a food bowl marked by the excretory deposits of conspecifics and that this mechanism can result in the communication and social learning of food preferences (Laland & Plotkin, 1991). Here we investigate whether a tradition of food and food site preferences can become established by these means. Experiment 1 established that the residual cues deposited by rats lose their powers of communication as “markers” of food sites over a 72-h period. Experiment 2 showed that while a socially enhanced preference for one flavored diet could be transmitted from one animal to the next along a chain, it was unstable for an alternative diet. This suggests that social transmission may be more stable when it reinforces a prior preference than when it conflicts with one. In Experiment 3, the stability of socially transmitted food preferences was bolstered by the addition of a second process for the communication of diet preferences-namely, gustatory cues on the demonstrator’s breath. This finding suggests that when a socially transmitted trait is mediated by more than one process, the processes may interact, and the diffusion is likely to be more stable.     

Functional differentiation of adjunctive drinking and wheel running in rats

Food-deprived rats were exposed to a schedule in which a brief stimulus was presented approximately once every 60 sec. The first leverpress to occur in the presence of the stimulus always turned it off, and produced a food pellet 50% of the time. When the rats were given concurrent access to water, a running wheel, or both, drinking predominated during intervals initiated by pellet delivery, while running predominated during intervals initiated without food. When allowed to obtain all of their food pellets at the beginning of a session, rats drank less and ran more than when the intermittent schedule was in effect, and most drinking occurred within the first half of the session, while running was distributed throughout the session. Adjunctive drinking and wheel running appear to be functionally different, drinking being schedule-induced and food-bound, running being neither.     

STEM Motivation Interventions for Adolescents: A Promising Start,but Further to Go

One way to increase students’ participation in science, technology, engineering, and mathematics (STEM) fields is to target their motivation. Researchers have conducted a growing number of interventions addressing students’ motivation in STEM; however, this body of work has not been adequately reviewed. We systematically reviewed experimental and quasi-experimental studies (n = 53) targeting adolescent students’ motivation for STEM subjects. While some interventions showed positive effects on a variety of motivational constructs and academic outcomes, others showed mixed or non-significant effects. We recommend that researchers more frequently examine moderating variables that might limit interventions’ results, including individual-level variables such as gender, contextual-level variables such as the subject in which an intervention was conducted, and design-level variables such as intervention length. Additionally, researchers might better align their interventions with motivation theory. Future research should address these limitations so that the results of successful interventions can better inform educational policy and practice.     

Poison-avoidance learning to food-related tactile stimuli: Avoidance of texture cues by rats

Rats injected with lithium chloride after ingesting familiar food pellets presented in textured metal sleeves learned aversions to the sleeved food. In a choice between sleeved and unsleeved food, the aversions were evident following conditioning with toxicosis delayed as long as 120 min after exposure to the sleeved food (Experiment 1). Texture-specific aversions resulted from procedures in which rats were exposed to food in both rough- and smooth-textured sleeves but were injected with lithium only in conjunction with one of the textures (Experiments 2–4). This differential aversion learning occurred when lithium treatment was delayed 30 min after exposure to the sleeved food (Experiments 3 and 4) and was equally evident in rats conditioned and tested in total darkness or in normal room-level illumination (Experiment 4). However, differential texture aversion learning was not observed with 90- or 300-min delayed toxicosis (Experiment 3). The present experiments highlight the importance of tactile cues in the poison-avoidance learning of species that handle their food during the course of ingestion.     

Reading motivation,perceptions of reading instruction and reading amount: a comparison of junior and senior secondary students in Hong Kong

This study examined the relations between students' reading motivation, perceptions of reading instruction and reading amount, together with grade differences, in a Chinese educational context. A total of 1,146 students from 19 secondary schools in Hong Kong voluntarily responded to a questionnaire that measured these three sets of variables. The study's findings indicated that students' intrinsic motivation was most strongly related to their reading amount. Students' perceptions of the reading instruction they received in their Chinese language class were significantly related to their reading motivation, but were only indirectly related to their reading amount, being mediated through reading motivation. Consistent with previous studies, significant grade differences were found in all types of reading motivation, students' perceptions of reading instruction and students' reading amount. The findings indicated that junior secondary students had better self‐efficacy, intrinsic motivation, extrinsic motivation and social motivation than senior secondary students. The largest grade difference was in students' self‐efficacy. Junior secondary students also perceived the reading instruction in their Chinese language class as more mastery‐oriented and read more frequently than senior secondary students. The implications of these findings for understanding Chinese students' reading motivation and for planning effective reading instruction to enhance their motivation are discussed.     

动机的自我决定理论在行为改变中的应用

动机的自我决定理论是由美国心理学家Deci和Ryan提出的动机过程理论。它不是把动机看作一个单一的概念,也不是把动机简单地区分为内部动机和外部动机,而是把动机看作一个连续体,从外部动机到内部动机需要经历三个内化程度不同的中间水平。近来的研究者发现,动机水平不同对行为改变效果的影响不同。在此理论的基础上,Ryan提出一个行为改变和保持的模型。同时,研究者还发现基于自我决定理论的心理治疗与动机性访谈技术有很多相似之处,且他们可以相互补充。     

Further evidence that Norway rats do not socially transmit learned aversions to toxic baits

Three experiments were undertaken to examine the effects of interactions with demonstrator rats made ill by injection of lithium chloride (LiCl) on the later food choices of their observers. We found that (1) observer rats that had been taught an aversion to an unfamiliar diet exhibited a substantial reduction of that aversion after interacting with poisoned demonstrators that had eaten the diet to which the observers had learned an aversion, (2) exposure of an observer rat to poisoned demonstrator rats that had eaten a diet interfered with later acquisition by the observer of an aversion to the diet that the poisoned demonstrators had eaten, and (3) after interacting with poisoned demonstrators that had eaten one of two diets, observers that ate both diets and were then made ill formed an aversion to whichever diet their respective, poisoned demonstrators had not eaten. The present experiments, like previous studies both in our laboratory and elsewhere, failed to provide any evidence that naive observer rats will learn to avoid a food as a result of interacting with demonstrator rats that had eaten the food and exhibit symptoms of toxicosis. To the contrary, observer rats in the present experiments exhibited an enhanced preference for foods eaten by sick demonstrators.     

Gender differences in adolescents’ academic motivation and classroom behaviour

The present study investigated gender differences in adolescents’ academic motivation and classroom behaviour and gender differences in the extent to which motivation was associated with, and predicted, classroom behaviour. Seven hundred and fifty students (384 boys and 366 girls) aged 11–16 (M age?=?14.0, 1.59 SD) completed a questionnaire examining academic motivation and teachers completed assessments of their classroom behaviour. Girls generally reported higher levels of academic motivation, whilst teacher reports of behaviour were poorer for boys. Interestingly, boys’ reported levels of academic motivation were significantly more closely associated with teacher reports of their classroom behaviour. Furthermore, cognitive aspects of boys’ motivation were better predictors of their classroom behaviour than behavioural aspects. On the other hand, behavioural aspects of girls’ motivation were better predictors of their behaviour. Implications for understanding the relationship between motivation and behaviour among adolescent boys and girls are discussed, in addition to interventions aimed at improving adolescents’ classroom behaviour.