Rats show no preference between free and earned water in an advance-response procedure

Although an arbitrarily specified instrumental response may persist when free reinforcers are concurrently available, the interpretation that earned reinforcers are preferred is tenuous. The present advance-response procedure used both time allocation and advance response rates as indices of preference between free and earned water in rats. When multiple schedule components were two response-dependent schedules with different overall reinforcement rates, higher rates of reinforcement were preferred. However, when the multiple schedule consisted of response-dependent and response-independent components equated for overall rates of reinforcement, no consistent preference for free or earned reinforcers was evident. That a preference for free reinforcers was not obtained is difficult to reconcile with concepts of least effort.     

Blocking despite changes in reinforcer identity

Rats were trained on a discriminated operant barpressing task according to a standard blocking design. In some conditions, the reinforcer was changed between the pretraining and compound conditioning phases; for other conditions, the reinforcer remained the same across phases. In three separate experiments using both between- and within-subject designs, strong blocking effects occurred regardless of the change in the reinforcer. In a fourth experiment, a multiple schedule of reinforcement was used in which response-independent reinforcers were superimposed on the schedule of response-contingent reinforcers. The degree of response suppression caused by the free reinforcer was greater when the free reinforcers were the same as the response-contingent reinforcers than when they were different. The role played by the reinforcer identity in contingency experiments thus appears to be different from the role it plays in blocking experiments.     

Conducting Preference Assessments and Reinforcer Testing for Individuals With Profound Multiple Disabilities: Issues and Procedures

The purpose of this article is to review the current research on preference assessment and reinforcer testing for individuals with profound multiple disabilities (PMD). It briefly reviews the literature that describes a subpopulation of individuals with PMD distinct from the general population of individuals labeled as having profound disabilities. The article describes the types of preference assessment procedures that have been used with individuals with PMD. Results from 13 published studies, which assessed preferences and tested reinforcers with individuals with PMD, suggest that preference procedures currently used with individuals at the higher levels of profound disabilities and individuals with severe disabilities are not always successful in identifying preferred stimuli that function as consistent reinforcers for individuals with PMD. Based on this review and other studies over a 3-year period, this article provides a rationale for conducting preference assessments to assist in curriculum development and describes a process for conducting preference assessments and targeting social, affective, and motor behaviors to increase with individuals with PMD.     

The role of response-reinforcer associations increases throughout extended instrumental training

Two experiments examined the effects of extended training on the development of response-reinforcer associations. Rats were trained by using various food reinforcers to make multiple instrumental responses. Subsequently, those reinforcers were devalued by being paired with a toxin. The presence of response-reinforcer associations was inferred from the decrease in the likelihood of a response following devaluation of its reinforcer. Such response-reinforcer associations are known to contribute to performance after moderate amounts of training. These experiments addressed the question of whether the contribution of those associations remains constant, increases, or decreases with more extended training. Experiment 1 found that even after a response had been extensively trained with one reinforcer, the substitution of a new reinforcer produced new associations between the response and that new reinforcer. After extended training, a response continued to acquire new associations with a reinforcer, as indexed by the impact of a devaluation procedure. Experiment 2 directly compared the contribution of reinforcers used extensively and moderately with the same response. It found that devaluation of the extensively used reinforcer more effectively reduced performance of the response, suggesting that the associations formed with additional training contribute to performance of the response. These experiments indicate that the contribution of response-reinforcer associations does not decrease but, instead, continues to grow throughout the course of extended instrumental training.     

Choice, delay, probability, and conditioned reinforcement

The hyperbolic-decay model is a mathematical expression of the relation between delay and reinforcer value. The model has been used to predict choices in discrete-trial experiments on delay-amount tradeoffs, on preference for variable over fixed delays, and on probabilistic reinforcement. Experiments manipulating the presence or absence of conditioned reinforcers on trials that end without primary reinforcement have provided evidence that the hyperbolic-decay model actually predicts the strength of conditioned reinforcers rather than the strength of delayed primary reinforcers. The model states that the strength of a conditioned reinforcer is inversely related to the time spent in its presence before a primary reinforcer is delivered. A possible way to integrate the model with Grace’s (1994) contextual-choice model for concurrent-chain schedules is presented. Also discussed are unresolved difficulties in determining exactly when a stimulus will or will not serve as a conditioned reinforcer.     

Novelty and partibility as determinants of hoarding in the albino rat

Experiments on object preferences indicate that there are at least two characteristics that induce albino rats to hoard inedible objects: partible objects are hoarded in preference to nonpartible objects, and novelty results in hoarding when other object-characteristics are controlled. In addition, novel objects may be hoarded by food-deprived rats in preference to food pellets. Hoarding can therefore be integrated into a number of other motivational systems. It is suggested that an incentive concept is necessary to explain hoarding preferences in this species.     

Rats’ choices between one and two delayed reinforcers

Rats chose between alternatives that differed in the number of reinforcers and in the delay to each reinforcer. A left leverpress led to two reinforcers, each delivered after a fixed delay. A right leverpress led to one reinforcer after an adjusting delay. The adjusting delay was increased or decreased many times in a session, depending on the rat’s choices, in order to estimate an indifference point& #x2014;a delay at which the two alternatives were chosen about equally often. Both the number of reinforcers and their individual delays affected the indifference points. The overall pattern of results was well described by the hyperbolic-decay model, which states that each additional reinforcer delivered by an alternative increases preference for that alternative but that a reinforcer’s effect is inversely related to its delay. Two other possible delay-discounting equations, an exponential equation and a reciprocal equation, did not produce satisfactory predictions for these data. Adding an additional free parameter to the hyperbolic equation as an exponent for delay did not appreciably improve the predictions, suggesting that raising delay to some power other than 1.0 was unnecessary. The results were qualitatively similar to those from a previous experiment with pigeons (Mazur, 1986), but quantitative differences suggested that the rates of delay discounting were several times slower for rats than for pigeons.     

Temporal integration and instrumental conditioned reinforcement

Stimuli associated with primary reinforcement for instrumental behavior are widely believed to acquire the capacity to function as conditioned reinforcers via Pavlovian conditioning. Some Pavlovian conditioning studies suggest that animals learn the important temporal relations between stimuli and integrate such temporal information over separate experiences to form a temporal map. The present experiment examined whether Pavlovian conditioning can establish a positive instrumental conditioned reinforcer through such temporal integration. Two groups of rats received either delay or trace appetitive conditioning in which a neutral stimulus predicted response-independent food deliveries (CS1→US). Both groups then experienced one session of backward second-order conditioning of the training CS1 and a novel CS2 (CS1–CS2 pairing). Finally, the ability of CS2 to function as a conditioned reinforcer for a new instrumental response (leverpressing) was assessed. Consistent with the previous demonstrations of temporal integration in fear conditioning, a CS2 previously trained in a trace-conditioning protocol served as a better instrumental conditioned reinforcer after backward second-order conditioning than did a CS2 previously trained in a delay protocol. These results suggest that an instrumental conditioned reinforcer can be established via temporal integration and raise challenges for existing quantitative accounts of instrumental conditioned reinforcement.     

Evaluation of stimulus preference assessment methods with general education students

The current exploratory study examined the ability of three stimulus preference assessments to identify effective reinforcers for general education students. Four students from Grades K through 5 and their teachers participated. A student nomination, teacher nomination, and ongoing (daily) stimulus preference assessment were evaluated. The results demonstrate that reinforcers identified by both general education students and their teachers increased behavior similarly, although correspondence between teacher‐ and student‐selected items themselves were low. Evaluation of the procedures indicated the highest rate of responding occurred under the ongoing reinforcer assessment condition for 3 of the 4 students. Limitations and future research are discussed. © 2008 Wiley Periodicals, Inc.     

The effect of rate of reinforcement and time in session on preference for variability

Pigeons pecked keys on concurrent-chains schedules that provided a variable interval 30-sec schedule in the initial link. One terminal link provided reinforcers in a fixed manner; the other provided reinforcers in a variable manner with the same arithmetic mean as the fixed alternative. In Experiment 1, the terminal links provided fixed and variable interval schedules. In Experiment 2, the terminal links provided reinforcers after a fixed or a variable delay following the response that produced them. In Experiment 3, the terminal links provided reinforcers that were fixed or variable in size. Rate of reinforcement was varied by changing the scheduled interreinforcer interval in the terminal link from 5 to 225 sec. The subjects usually preferred the variable option in Experiments 1 and 2 but differed in preference in Experiment 3. The preference for variability was usually stronger for lower (longer terminal links) than for higher (shorter terminal links) rates of reinforcement. Preference did not change systematically with time in the session. Some aspects of these results are inconsistent with explanations for the preference for variability in terms of scaling factors, scalar expectancy theory, risk-sensitive models of optimal foraging theory, and habituation to the reinforcer. Initial-link response rates also changed within sessions when the schedules provided high, but not low, rates of reinforcement. Within-session changes in responding were similar for the two initial links. These similarities imply that habituation to the reinforcer is represented differently in theories of choice than are other variables related to reinforcement.     

The PISA mathematics regime: knowledge structures and practices of the self

Within mathematics education research, the responses to the Programme for International Student Assessment’s (PISA’s) international testing regime tend to accept its framework and results as necessary points of reference, even when offering a critical reinterpretation or challenging national policy discourses based on PISA. In this article, we offer a different approach to the critique of PISA, drawing on theoretical tools provided by Bernstein and Foucault, to ask what the PISA regime achieves. Our understanding of this achievement encompasses both the production of knowledge structures and the production of students, teachers and other agents as subjects. We propose that the theoretical approach we offer provides a methodological entry point into analysis of the texts comprising the PISA mathematics regime. Analysis of a single PISA item is used to illustrate the insights that may be gained from such a theoretical lens. Such insights into the logic of PISA have the potential to allow us better to understand and hence contest the role that PISA and other large-scale assessment regimes may play in global and local policy discourses.     

The effects of early rearing conditions upon responses to mirror-image stimulation in domestic chicks and turkeys

Two experiments were performed in which either White Plymouth Rock chicks or domestic turkeys were reared under three maintenance conditions (with a mirror, with a conspecific, or in visual isolation) from Day 1 posthatch until Day 7. On Day 7, the Ss were given a preference test to determine whether they spent more time before a mirror or with another bird. Ss reared with a mirror spent approximately two-thirds of their time in the vicinity of the mirror, whereas socially reared Ss spent approximately two-thirds of their time with an agemate. The social isolates, on the other hand, failed to show a preference for either mirror image of conspecific stimulation. A third experiment evaluated the choice behavior of turkeys socially reared in the presence of a mirror, and revealed that, like the social isolates, these Ss also failed to exhibit a reliable preference. The results are interpreted in terms of the effects of early rearing conditions upon social stimulus preferences.     

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.     

Programmed student achievement: A Hawthorne Effect?

Three groups of college students were given instructions using different testing techniques to determine whether the superior performance obtained with Programmed Student Achievement (PA) was due to a Hawthorne Effect. PA students, operating under the consequence of failing the course if they failed to evidence criterion performance (100% mastery) on weekly quizzes, exhibited superior performance, relative to control groups, on the weekly quizzes and on an unannounced retention test. The results seem to preclude any attempt to interpret the effectiveness of Programmed Student Achievement on the basis of a Hawthorne Effect.     

Behavioral inhibition induced by ingestion in sea anemones (Anthopleura elegantissima)

Following tests for initial responsiveness, the suppressive effect of ingestion ofArtemia salina on the contraction response of the sea anemone,Anthopleura elegantissima, was assessed. During testing, repeated presentations of a water-stream stimulus occurred over a period of 70 min. All subjects also underwent control testing in which the water-stream sequence was presented in the absence of priorArtemia ingestion. Significant suppression of oral disk contraction to the water stream was observed followingArtemia ingestion with and without water exchange during testing. The relationship of this finding to similar results obtained withHydra is discussed.     

Towards fairer assessment

Drawing on the largest Australian collection and analysis of empirical data on multiple facets of Aboriginal and Torres Strait Islander education in state schools to date, this article critically analyses the systemic push for standardized testing and improved scores, and argues for a greater balance of assessment types by providing alternative, inclusive, participatory approaches to student assessment. The evidence for this article derives from a major evaluation of the Stronger Smarter Learning Communities. The first large-scale picture of what is occurring in classroom assessment and pedagogy for Indigenous students is reported in this evaluation yet the focus in this article remains on the issue of fairness in student assessment. The argument presented calls for “a good balance between formative and summative assessment” (OECD, Synergies for Better Learning An International Perspective on Evaluation and Assessment, Pointers for Policy Development, 2013) at a time of unrelenting high-stakes, standardized testing in Australia with a dominance of secondary as opposed to primary uses of NAPLAN data by systems, schools and principals. A case for more “intelligent accountability in education” (O’Neill, Oxford Review of Education 39(1):4–16, 2013) together with a framework for analyzing efforts toward social justice in education (Cazden, International Journal of Educational Psychology 1(3):178–198, 2012) and fairer assessment make the case for more alternative assessment practices in recognition of the need for teachers’ pedagogic practice to cater for increased diversity.     

Symptoms of attention-deficit hyperactivity disorder (ADHD) and home learning environment (HLE): findings from a longitudinal study

The concept of “Home Learning Environment” (HLE) covers activities in a family providing intellectual stimulation for a child, such as reading to him or her or visiting libraries. Numerous studies have shown an association between HLE and children's cognitive development. In this longitudinal study, we focus on HLE as a predictor for children's behavioral development, namely, for later symptoms of attention-deficit hyperactivity disorder (ADHD), controlling for relevant aspects like socioeconomic status (SES), or television viewing behavior. We analyzed the development of ADHD symptoms from kindergarten to the end of grade 2 and possible associations with HLE, SES, and television exposure, using a German community sample (N?=?924). Results indicated that ADHD symptoms were negatively and significantly correlated to HLE for all five measurement points as well as to SES (except T4) and to television exposure for T1 to T4. Observing later development, only early HLE but not SES or television exposure served as a significant predictor for ADHD symptoms at school, when age, sex, and ADHD symptoms in kindergarten were controlled for. A structural equation model showed that HLE acted as a mediator between SES and later ADHD symptoms. Our results highlight the importance of the concept of home learning environment also for children's behavioral development. As a consequence, parents should be supported in offering their children a more favorable learning environment.     

Retrospective and prospective short-term memory in delayed response tasks in rats

Separate groups of rats were trained and tested on asymmetrically and symmetrically reinforced successive delayed matching-to-sample (DMTS) or delayed discrimination (DD) tasks in Experiment 1. Each rat received training and testing on symmetrically reinforced DMTS and DD tasks in Experiment 2. The only difference between each task was that the rats had to respond correctly to a light or tone test stimulus, S₂, if it matched a light or tone sample stimulus, S₁, in DMTS, but could respond to either S₂ if S₁ had been a particular stimulus in DD. Only correct leverpresses were reinforced in the asymmetrically reinforced version of each task. Both correct presses and correct omissions were reinforced in the symmetrically reinforced version of each task. Response biases to leverpress during tests for delayed responding to S₁ were reduced in both symmetrically reinforced tasks, but only in the DD task did such contingencies produce consistently poorer performance in responding to either S, in Experiment 1. Declines in accuracy of performance that occurred in both experiments were greater to the visual than to the auditory S₁ only in the DMTS tasks with increased intervals between S₁ and S₂. A third experiment, in which rats had to respond to S₂ if it matched S₁ (DMTS) or if S₂ mismatched S, (DMmTS), was carried out. Modality of S₁ similarly affected accuracy of delayed responding in each task, as in the first two experiments. Methodological and theoretical implications of these results are discussed in terms of Honig and Thompson’s (1982) dual-process theory of working memory.     

Temporal discounting of aversive consequences in rats

Previous research has extensively evaluated the impact of delay on the value of positive reinforcers, but the study of its impact on the value of aversive consequences is scarce. The present study employed a modification of Evenden and Ryan’s procedure (1996, Psychopharmacology, 128(2), 161–170) to obtain data on temporal discounting of an aversive consequence, with rats as experimental subjects. In the first phase of the procedure, rats chose between one-pellet and four-pellet alternatives; when subjects developed preference for the larger-amount alternative, a shock was added to it, resulting in a loss of preference. In the first experimental condition, the delay to shock was progressively increased within each session from zero to 40 s (ascending delays), which resulted in a recovery of the preference for the larger-amount + shock alternative as the delay to shock was increased. In a subsequent condition (descending delays) the delay to shock was progressively decreased within each session, from 40 to 0 s. In both conditions, the preference for the smaller-amount no-shock alternative was well described by a hyperbolic function. The order of presentation of the delays within the session, ascending or descending, did not alter the relationship between preference and delay to shock. The temporal discounting curve obtained in the present study could represent a baseline for analyzing the impact that diverse environmental and pharmacological variables have on the temporal discounting of aversive consequences.     

Analysing novices analysing Prolog: what stories do novices tell themselves about Prolog?

Informal observations of Prolog learners showed that, despite being presented with correct information and models, students still tended to construct their own idiosyncratic explanations of events, and, characteristically, they defended these ‘stories’ fiercely when tutorial intervention was attempted. Although the stories were often so flawed that the student's future progress was potentially hampered, it was nevertheless true that learning could not have proceeded at all without them. It seems that if we are to understand the novice Prolog programmer, we need to know about these stories, their source, and what, if anything, they have in common from one learner to another. Pain and Bundy (1987) posed the question “What stories should we tell novice Prolog programmers?” in order to teach them Prolog. In our research, we ask: “What stories do novices Prolog programmers tell themselves?” in order to learn Prolog. Observational studies undertaken showed that students used tacit knowledge of human discourse processes both to interpret the language used to communicate with the computer and to interpret the behaviour of the machine. Students did not appreciate the fundamental differences between natural discourse (as takes place amongst humans) and formal discourse (as takes place between humans and machines), and confused elements of the discourse levels. This can be an effective initial learning strategy, but unless its limitations are recognised, programs are inevitably incomplete at some level. Examples from these studies are reported here with illustrative protocol fragments.