Signal-directed behavior in the rat: Interactions between the nature of the CS and the nature of the UCS

Two experiments are described, which involved the investigation of interactions between the nature of the conditioned stimulus (CS) and the nature of the unconditioned stimulus (UCS) in producing signal-centered behavior. In Experiment 1, rats received response-independent heat reinforcement in a cold environment. For some groups, this heat UCS was signaled by presentations of a standard aluminum retractable lever; for other groups, it was signaled by a retractable lever covered in acrylic fur (furry lever CS). Only the subjects that received the furry lever CS paired with heat exhibited differential CS-contact behavior, when compared with unpaired, aluminum lever, and warm control subjects. In Experiment 2, hungry rats received pairings of either an aluminum or a furry lever with food (UCS). When compared with unpaired controls, only the subjects that received the aluminum lever paired with food showed differential signal-directed behavior; the subjects receiving the furry lever CS did not show differential contact with the CS, but instead exhibited differential food tray entry behavior during CS presentation. In the two studies, the signal-directed behavior exhibited by subjects resembled either thermoregulatory or feeding behaviors characteristic of rats. The results suggest that signal-directed behavior is determined by a complex interaction between the ecological relevance of the CS and the nature of the UCS—an interaction that can best be described in terms of a behavior systems model of conditioned responding.     

Neurophilia: Guiding Educational Research and the Educational Field?

For a decade or so there has been a new ‘hype’ in educational research: it is called educational neuroscience or even neuroeducation (and neuroethics)—there are numerous publications, special journals, and an abundance of research projects together with the advertisement of many positions at renowned research centres worldwide. After a brief introduction of what is going on in the ‘emerging sub‐discipline’, a number of characterisations are offered of what is envisaged by authors working in this field. In the discussion that follows various problems are listed: the assumption that ‘visual proof’ of brain activity is supposedly given; the correlational nature of this kind of research; the nature of the concepts that are used; the lack of addressing and possibly influencing the neurological mechanism; and finally the need for other insights in educational contexts. Following Bakhurst and others, a number of crucially relevant philosophical issues are highlighted. It is argued that though there are cases where neuroscience insights may be helpful, these are scarce. In general, it is concluded, not a lot may be expected from this discipline for education and educational research. A reminder is offered that the promise of neurophilia may be just another neuromyth, which needs to be addressed by philosophy and education.     

A Peircean Socio-Semiotic Analysis of Science Students’ Creative Reasoning as/Through Digital Simulations

Research in Science Education - In science education, there is a now established focus on fostering students’ meaning making through/as multimodal representations as part of their induction...     

Exploring socioeconomic inequalities and access to elite postgraduate education among English graduates

Higher Education - A worldwide trend towards high levels of participation in higher education, paired with concerns about the post-university destinations of an increasing pool of graduates, have...     

Deficiency,Contamination, and the Signal Processing Metaphor

Educational assessment involves eliciting, transmitting, and receiving information concerning the level of proficiency of a learner in a specified domain. With that in mind, it is perhaps surprising that the literature seems to make very little use of the signal processing metaphor. The present article begins by making a general case for greater use of this metaphor, as a simple and intuitive thinking tool for helping to explain how educational assessment works. The main body of the article extends this argument by demonstrating the utility of the metaphor in helping to explain how educational assessment can go wrong. During the 1980s and 1990s, Samuel Messick extensively discussed two major ways in which educational assessment can go wrong via construct-irrelevant variance and construct underrepresentation, respectively. Despite their importance, these concepts have had only a limited impact on the literature. Part of the reason for this may be a lack of clarity and comprehensiveness in their articulation. The present article aims to articulate these concepts more clearly and comprehensively, within a framework provided by the signal processing metaphor, reconfiguring them as signal contamination and signal deficiency, respectively.     

Participatory technology development in Cameroon: The route and milestone in the process of its institutionalisation

Summary

The four-year Phase II of the action-research programme "Indigenous Soil and Water Conservation in Africa (ISWC II) started in December 1996 and operates in the French-speaking countries Tunisia, Burkina Faso and Cameroon and in the English-speaking countries Ethiopia, Uganda, Tanzania, and Zimbabwe. It had received a budget-neutral extension from the funders (Netherlands Development Aid, DGIS) for the entire 2001.

This paper is based on the Participatory Technology Development (PTD) experiences with the ISWC II project in Cameroon. The ISWC II project aimed to improve the effectiveness of both indigenous and modern Soil and Water Conservation (SWC) practices through a process of joint experimentation involving farmers, scientists and development agents.

The authors have developed the informal and formal strategies used and their impacts in the process of the institutionalisation of the PTD approach in Cameroon.     

The Categorization of Above and Below Spatial Relations by Young Infants

3 experiments using the familiarization-novelty preference procedure were conducted to investigate whether 3-month-old infants could form categorical representations of the spatial relations above and below. In Experiment 1, one group of infants familiarized with exemplars depicting a dot in different positions above a horizontal bar displayed a subsequent visual preference for a novel category exemplar (dot below bar) that was paired with a familiar category exemplar (dot in novel position above bar). A second group of infants presented with exemplars in which the dot appeared in variable locations below the bar also responded preferentially to a novel category exemplar (dot above bar) when it was paired with a familiar category exemplar (dot in new position below bar). These preferences did not result from the salience of vertical up-down changes in dot position or the encoding of dot positions relative to an internal horizontal midline (Experiment 3) or from an inability to discriminate the members of each category (Experiment 2), but rather would seem to be a consequence of the ability to represent categorically the spatial relations above and below. The data provide evidence for early categorical organization in human spatial memory.