Performance factors in associative learning: Assessment of the sometimes competing retrieval model

Previous simulations revealed that the sometimes competing retrieval model (SOCR; Stout & Miller, Psychological Review, 114, 759-783, 2007), which assumes local error reduction, can explain many cue interaction phenomena that elude traditional associative theories based on total error reduction. Here, we applied SOCR to a new set of Pavlovian phenomena. Simulations used a single set of fixed parameters to simulate each basic effect (e.g., blocking) and, for specific experiments using different procedures, used fitted parameters discovered through hill climbing. In simulation 1, SOCR was successfully applied to basic acquisition, including the overtraining effect, which is context dependent. In simulation 2, we applied SOCR to basic extinction and renewal. SOCR anticipated these effects with both fixed parameters and best-fitting parameters, although the renewal effects were weaker than those observed in some experiments. In simulation 3a, feature-negative training was simulated, including the often observed transition from second-order conditioning to conditioned inhibition. In simulation 3b, SOCR predicted the observation that conditioned inhibition after feature-negative and differential conditioning depends on intertrial interval. In simulation 3c, SOCR successfully predicted failure of conditioned inhibition to extinguish with presentations of the inhibitor alone under most circumstances. In simulation 4, cue competition, including blocking (4a), recovery from relative validity (4b), and unblocking (4c), was simulated. In simulation 5, SOCR correctly predicted that inhibitors gain more behavioral control than do excitors when they are trained in compound. Simulation 6 demonstrated that SOCR explains the slower acquisition observed following CS-weak shock pairings.     

The dual role of the context in postpeak performance decrements resulting from extended training

The context??s role in Pavlovian conditioning depends on the trial spacing during training, with massed trials revealing a function akin to that of discrete stimuli, and spaced trials revealing a modulatory function (Urcelay & Miller, Journal of Experimental Psychology. Animal Behavior Processes, 36, 268?C280, 2010). Here we examined the contextual determinants of a common but largely ignored effect: attenuated conditioned responding with extended reinforced training (i.e., a postpeak performance deficit [PPD]). Contextual sources of PPDs were investigated in four fear-conditioning experiments with rats. In Experiment 1, as the number of reinforced trials increased, conditioned responding decreased, even when testing occurred outside the training context. Experiment 2 revealed opposing influences of context on the PPD based on trial spacing, which interacted with whether testing occurred in the training context. This finding reconciles Experiment 1??s results with previous data (Bouton, Frohardt, Sunsay, Waddell, & Morris, Journal of Experimental Psychology. Animal Behavior Processes, 34, 223?C236, 2008). Experiment 3 suggested that extended training with these parameters did not lead to habituation to conditioned or unconditioned stimuli. In Experiment 4, few or many massed training trials were followed orthogonally by context extinction or no context extinction. After many pairings, context extinction reduced the PPD (i.e., enhanced responding), suggesting a competitive role of the context. These results, together with prior data suggesting that context modulates expressions of the PPD, are consistent with the view that contexts can play two distinctly different roles.     

Early detection of fungal biomass on library materials

Library materials are susceptible to fungal deterioration. The paper constituents of archival materials are subjected to harmful physical and chemical processes as they are slowly consumed by fungi. Remediation of fungal contamination can be costly and risk further damage to fragile or previously degraded materials. Early detection of fungal growth would permit the use of relatively noninvasive treatments to remediate fungal contamination of artifacts before visible or lasting damage has occurred. Current methods used for the detection of microbial biomass, such as colony counts, microscopic biovolume estimation, and ergosterol analysis are expensive, time consuming, or are inappropriate for use with fungi. Beta-N-acetylhexosaminidase (EC 3.2.1.52) activity provides a rapid and reliable means of fungal detection on a variety of cultural heritage materials. Adapted for use on archival materials, fluorogenic 4-Methylumbelliferyl (MUF) labeled substrate N-acetyl-Beta-D-glucosamine (NAG) was used to detect fungal beta-N-acetylhexosaminidase activity. The fluorescence generated by minute quantities of fungi was quickly detected at an early stage of growth. The sensitivity of the assay was comparable to other biochemical techniques. The fluorometric assay was well-suited for early detection of fungal biomass on paper and assessment of the effectiveness of common remediation practices.     

The Appraisal of Academic Conduct: Are Norms an Adequate Moral Guide?

This paper examines the legitimacy of norms as a means of evaluating academic conduct. Section one provides a general overview of some issues involved. In section two the concept of norms is unpacked and, in section three, some problems with an adequate account of norms are identified. In section four the rationality of norms is examined and in the following section, section five, the concept of deviance is discussed. It is argued that deviance from rational academic norms is usually, but not always, unacceptable. However, it also is suggested that dissenting conduct is required of academics since it is a central professional norm, closely connected to the purposes of a university. The concept of academic freedom, whilst not examined in any detail in this paper, provides a general defence of dissenting–but, in general, not of deviant ‐conduct. Given the difficulties associated with the concept of norms, the importance of character over conduct is emphasised. It is concluded that the moral basis for evaluating academic conduct and, hence, attempts to improve university teaching, is seriously problematic.     

A Method for Investigating College Student Peer Group Holding Power

The interaction of group prestige among groups, dissonance of new member attitudes with those of the established group, and homogeneity of established group attitudes, were dependent variables studied. Groupattrition rate was the independent variable. The data consisted of attitude scores, group prestige ranks, and attrition statistics. Analysis was by the method of partial correlations. College fraternity chapters (N = 19) were the subject groups. It was concluded that no differences exist on the dimensions posited, however, trends of results seemed to support the theoretical notions. The method utilized should be explored further.     

The nature of citizenship education provision: an initial study

While compulsory citizenship education has apparently been accepted and, in some quarters, regarded as overdue, in schools there has been little opportunity to discuss the meaning of ‘citizenship’. This article reports an initial study of four schools, with a focus on one of them. From this study it was evident that teachers and students have different views about what they are offering and being offered. Some implications of the spaces between these differences are aired in the conclusion of the article.     

Book reviews

Takeshita, Masataka. Ibn ^cArabi's Theory of the Perfect Man and Its Place in the History of Islamic Thought. Tokyo: Institute for the Study of Languages and Cultures of Asia and Africa, 1987 (Studia Culturae Islamicae, 32). iii + 182 pp.

Pryor, John. H. Geography, Technology and War : Studies in the Maritime History of the Mediterranean, 649–1571. Cambridge: Cambridge University Press, 1988. xvii +238pp.;£ 22.50 / US$ 39.50.

Baali, Fuad. Society, State and Urbanism : Ibn Khaldun's Sociological Thought. Albany: State University of New York Press, 1988. 175 pp.; paper US$ 12.95, cloth US$ 34.50

Wilkinson, John (editor) with Hill, Joyce and Ryan, W.F., Jerusalem Pilgrimage 1099–1185. London: The Hakluyt Society,1988. xi + 372pp., 24 maps and plans; £ 16.00.

Heine, Peter. Kulinarische Studien: Vntersuchungen zur Kochkunst im arabisch‐islamischen Mittelalter. Wiesbaden: Otto Harrassowitz,1988. 137pp.; DM 68.     

Academic Loyalties and Professional Disobedience

A conflict of duties would be a relation of duties in which one of them would annul the other (wholly or in part). But a conflict of duties and obligations is inconceivable

Immanuel Kant, 1785

In this paper the issue of academic morality is raised in the context of real challenges to academic integrity, such as the application of invalid standard subject evaluations. In particular, five spheres of academic loyalties are postulated. The paper touches on a number of traditional moral positions and assesses them in regard to satisfying the demands of an academic ethics; that is, for their effectiveness in providing an adequate framework for the resolution of conflicts of duty. These positions are found to be wanting in scope or particular applications. The paper concludes by suggesting that the ethical foundations of academic conduct are not obvious and, thus, universities are vulnerable to external social forces which may vitiate their traditional role–the pursuit and promulgation of truth.