Learning about food: starlings, skinner boxes, and earthworms

Despite its importance as a tool for understanding a wide range of animal behavior, the study of reinforcement schedules in the laboratory has suffered from difficulties in the biological interpretation of its findings. This study is an operant-laboratory investigation of the ability of European starlings, Sturnus vulgaris, to learn to respond adaptively to the problem of foraging on patchily distributed prey that are uncertainly located in space. In order to maximize the biological relevance of the laboratory study, variation in the aggregation of earthworms, Lumbricus terrestris (a prey species), was rigorously quantified from the field, and the experimental birds were presented with reinforcement schedules designed to represent the extremes of the observed variation. The results demonstrate that, even for a single prey species, the degree to which individuals are aggregated can vary markedly over a range of spatial scales, and that starlings can rapidly learn to respond, in an adaptive manner, to these variations. These findings suggest that starlings are capable of adjusting their behavior to facilitate the efficient exploitation of prey that occurs in patches of an uncertain nature, and thus illustrate the heuristic value of an ecologically informed operant-laboratory approach to studying foraging behavior.     

How to Read Wittgenstein

"How to Read Wittgenstein" is a discussion of some misinterpretations that arise when Ludwig Wittgenstein's later works are read, not in their historical context, but as though they were written for a generation of philosophers influenced by G.E. Moore and ordinary language philosophy. The criticisms are directed primarily at Oswald Hanfling's "Critical Notice" in Philosophical Investigations 19:2 (April, 1996).     

The principle of reversibility: Some problems of interpretation

Summary and conclusion In summary, the question of how to construe the procedure called reversibility cannot be given an absolute answer. No one moral interpretation of the principle is universally applicable, that is, applicable to all moral issues. The decision concerning which to apply cannot be made a priori, but only in context - that is, only when we are faced with a particular moral problem. Moreover, there appears to be no rule which would enable us to choose which version is correct in a particular case. It is a matter of judgment.That the various versions represent a moral progression from lower to higher constructions is debatable. We have seen that the altruism of reversibility₃ - the ethic of care - may recommend itself in some personal relations to the point of making either version of reversibility₄ irrelevant. Similarly, it is not clear that reversibility₃ is always higher than reversibility₂. For example, parents in trying to decide what is morally best for a young child should often - in the spirit of the second construction - substitute the judgment of their mature selves for the judgment of the immature self of the child. Moreover, this substitution may not be justifiable in terms of either utility or autonomy.If I seem to have ignored reversibility₁ in this discussion that is because I consider it outside morality: it is, if anything, a principle of self-interested calculation. If Baier is correct in holding that we teach children to think morally when we get them to take the standpoint of others, that requires, I believe, getting them beyond the stage of crude reciprocity. If Piaget and Kohlberg are correct in their developmental claims, we cannot immediately teach children reversibility₄ but must help them progress through the other two versions. There is some basis for thinking that children can transcend egoism and sympathize with others much earlier than Kohlberg allows - an important consideration in the development of a system of moral education. That point has been pursued by Michael Pritchard in his critique of Kohlberg. My point is a different one: even granting Kohlberg's theory of development (which asserts, for example, that a particular cognitive ability is required to think like a Kantian), it does not follow that the moral thinking which accompanies the highest cognitive stage is morally superior to the moral thinking which accompanies the lesser cognitive stages. That it is cognitively easier to master reversibility₃ than reversibility₄ does not settle the question of which is morally superior.Rather than arguing about which moral version of reversibility is morally best- a pointless debate if the desirability of a version is understood as contingent upon appropriateness with respect to context - we should instead celebrate the richness of the concept of reversibility. In teaching students the moral point of view by getting them to put themselves in another's place, we would not be asking them to master a rigid formula, but rather to be sensitive to the decisional context and to make a thoughtful judgment about which version of reversibility is most appropriate to that context. We would not be teaching them either moral relativism or moral absolutism, but the complexity of trying to make a moral decision by applying an ancient and philosophically rich ethical principle.

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Preliminary report on construction and validation of a pediatric sleep disturbance questionnaire

A scale to assess sleep disturbance of children with developmental disabilities is reported. The scale has been used with a small sample of 14 children diagnosed as having Tourette Disorder, 36 physically handicapped children (cerebral palsy). Also, a group of 115 nonhandicapped Native American children were surveyed to assess whether the items might be appropriate for use with such children. The scale has 6 distinct factors and appears to have adequate reliability and validity.     

Concurrent validity of four androgyny instruments

Four sex-role instruments were administered to a group of 281 graduate and undergraduate students at an urban university. Concurrent validity was examined through the use of correlational and factor-analytic techniques. Seven problems in interpretation of the categorizations made by the several instruments were identified: (1) item homogeneity of individual scales; (2) convergence of corresponding scales and divergence of scales from their complements; (3) multifactoriality; (4) factor complexity; (5) distribution of content across instruments; (6) interaction between factor complexity and content balance; and (7) correspondence of classifications of subjects across instruments.     

Homotopic callosal inhibition

Previous theories concerning the function of the corpus callosum have included a “topographic” column-to-column excitatory theory and a diffuse “regional” inhibitory theory. Here it is shown that a topographic inhibitory model, in conjunction with a postulate concerning surround inhibition among cortical columns, produces complementary patterns of cortical column firing which, although qualitatively different, do not imply quantitative metabolic asymmetries. The cognitive implications of such homotopic inhibition are discussed.     

Effects of computer-mediated vocational guidance procedures: Accuracy of self-knowledge

To assess the effectiveness of vocational guidance procedures proposed for inclusion in a computer-based vocational exploration system, 128 11th-grade male subjects were randomly assigned to three experimental groups and a control group. One group was given a computer-generated accuracy of self-knowledge feedback, another group was taught on occupational classification scheme, a third group experienced both. Measures of self-knowledge showed increased accuracy about intelligence, but not about interests, after treatments that included the feedback. Increases were largely due to changes in subjects who originally underestimated their intelligence. A delayed posttest indicated that the increases did not persist.