Sustained attention, a key cognitive skill that improves during childhood and adolescence, tends to be worse in some emotional and behavioural disorders. Sustained attention is typically studied in non-affective task contexts; here, we used a novel task to index performance in affective versus neutral contexts across adolescence (N = 465; ages 11–18). We asked whether: (i) performance would be worse in negative versus neutral task contexts; (ii) performance would improve with age; (iii) affective interference would be greater in younger adolescents; (...) (iv) adolescents at risk for depression and higher in anxiety would show overall worse performance; and (v) would show differential performance in negative contexts. Results indicated that participants performed more poorly in negative contexts and showed age-related performance improvements. Those at risk of depression performed more poorly than those at lower risk. However, there was no difference between groups as a result of affective context. For anxiety there was no difference in performance as a function of severity. However, those with higher anxiety showed less variance in their reaction times to negative stimuli than those with lower anxiety. One interpretation is that moderate levels of emotional arousal associated with anxiety make individuals less susceptible to the distracting effects of negative stimuli. (shrink)

How do we acquire knowledge through a sensory input from our environment? In The Enigma of Perception, D.L.C. Maclachlan revives the traditional causal representative theory of perception which dominated philosophical thinking for hundreds of years by revealing the important element of truth the theory contained. The traditional theory was not a complete explanation of perception, because it presupposed a causal system including both the physical objects and the subjective experiences. The pattern of inference from sensations to external objects, which lies (...) at its heart, is nevertheless legitimate, because the assumptions on which it depends are generally recognized as true. The emerging enigma is how to explain this original knowledge of the world on which the traditional theory depends. The key idea is that sense experience is constructed as a response to sensory input - an act whose purpose is to represent a reality beyond the cognitive subject. The Enigma of Perception develops original ideas to explain this process in detail, with help from numerous philosophers from John Locke to David Chalmers. (shrink)

The working situation prevailing in theoretical and experimental physics today is held to be inseparable from the interpretation of quantum theory, and constitutes an embodiment of its implicit difficulties. Such an understanding of the present situation in fundamental physics provides a quite different basis for ideas than the formulation of alternative courses of action (experiments) or alternative forms of knowledge (theories), which proceeds from the belief in a full separation of theory from experiment in this field. It is argued that (...) this underlying belief is not well founded. One must therefore consider the technical details of the field together with its foundations, and thus especially the situation produced by fundamental physics, including, in particular, the growth of high-energy technology, which exerts a determining influence on the further course of the subject. (shrink)

In this thesis I shall summarize and critically examine the central features of the theories of values of four contemporary moral philosophers: A.J. Ayer, C.L. Stevenson, R.M. Hare, and P.H. Nowell - Smith. I shall first look back, however, to the theory of moral philosophy of the most influential 'forefather' of this group, David Hume. Hume's theory stands as a challenge to moral philosophers who would assume that moral judgments are primarily, in some sense, acts of 'reason'. Although our four (...) contemporaries follow Hume in this, his challenge, in the form I shall indicate shortly, will provide the main theme for this thesis. (shrink)

The causal representative theory of perception dominated theory of knowledge for hundreds of years after it was put on the map by Descartes and Locke. It is now almost extinct. How could this happen? The theory collapsed because it could not explain how we acquire knowledge of the external world, since it presupposes a causally organized system of external objects producing sensations in us. This presupposition, however, is generally recognized as true, so that the pattern of causal inference at the (...) heart of the theory is surely justified. The theory cannot explain how we originally acquire our knowledge of the external world, but it is entitled on a second pass to correct our empirical beliefs, where necessary. This includes replacing our naive picture of the physical world with a more sophisticated scientific conception, which downgrades secondary qualities. This was, indeed, the main reason why it was originally introduced by Descartes and Locke, and has been the source of its attraction over the years. (shrink)

Sperber and Wilson (1987) have criticised Fodor's (1983) pessimistic view about the possibility of a science of central systems. Fodor's pessimism stems from the holistic nature of central systems – people can access anything that they know when engaging in belief fixation. It is argued that Sperber and Wilsons theory of how relevance is realized during verbal comprehension fails to elucidate this crucial aspect of central processes. Their claims about how a context is selected are shown to presuppose the ability (...) to realize relevance. (shrink)

The nature of the Plague described by Thucydides in Book 2, chapter 49, has long been discussed both by medical and by classical scholars. Of numerous suggested identifications none has found general approval; and it is doubtful whether any opinion is more prevalent today than that the problem is insoluble. The classical scholar is handicapped by his ignorance of medical science; his medical colleague has often been led astray by translations deficient in exactitude if not disfigured by error. The difficulties (...) are great enough: but there is one indispensable preliminary task which can be undertaken with some prospect of success. If Thucydides' description is to be compared with modern records, it is necessary first to determine what the Greek words mean; and that can only be done by determining how far the Greek is expressed in the technical terms of contemporary medical science. It is obvious that Thucydides required a special vocabulary for this part of his work; and in fact over forty words in chapters 49 and 50 are unexampled elsewhere in his History, and a dozen more are used in meanings unexampled elsewhere. It is certain that a number of medical treatises were in circulation in Thucydides' lifetime, and that a more or less standard vocabulary had been or was being established. Now if it can be shown that the great majority of the terms employed by Thucydides in ch. 49 recur, apparently with the same meanings, as standard terms in the contemporary doctors, our second task—the comparison of Thucydides' description with modern records—will become a more rational undertaking than it was before, no longer the doubtful speculation which many of the modern doctors suppose it to be, thinking as they do that they have to deal with a layman's generalities expressed in literary language. (shrink)

Predictive modeling in education draws on data from past courses to forecast the effectiveness of future courses. The present effort sought to identify such a model of instructional effectiveness in scientific ethics. Drawing on data from 235 courses in the responsible conduct of research, structural equation modeling techniques were used to test a predictive model of RCR course effectiveness. Fit statistics indicated the model fit the data well, with the instructional characteristics included in the model explaining approximately 85% of the (...) variance in RCR instructional effectiveness. Implications for using the model to develop and improve future RCR courses are discussed. (shrink)