Developmental changes in mental rotation

Subjects from Grades 3, 4, 6, and college judged whether pairs of stimuli were identical or mirror-image reversals. One stimulus of a pair was presented upright; the other was rotated 0 to 150° from the standard. The pairs were either alphanumeric symbols or unfamiliar, letter-like characters of the type found on the PMA Spatial Ability Test. Response latencies were measured. The primary results were that (a) the speed of mental rotation increased with development, (b) unfamiliar characters were rotated more slowly than alphanumeric characters, by approximately the same amount at each grade, and (c) unfamiliar characters were encoded and compared more slowly than alphanumeric symbols, by an amount that declined with development. The results are discussed in terms of the component processes that underlie developmental change and individual variation in mental rotation skill.     

Components of geometric analogy solution

Geometric analogy solution was investigated as a function of systematic variations in the information structure of individual items. Latency data from the verification of true and false items indicated that individuals decompose figural patterns in a way that represents a sequential determination of the various elements that need to be isolated. They also appear to identify and evaluate the transformations applied to elements in a way that represents a sequential determination of the separate or successive transformations that fully specify an item rule. Analysis and evaluation of transformations took more time than element analysis and was the primary source of errors. The combined effects of element and transformation processing violated a simple additive model and the best fitting functions suggested that nonadditive increases in solution latency and error rates were due to working memory limitations associated with the representation and manipulation of item features at high levels of rule complexity. Correlational data also indicated that these factors partially account for individual differences in performance on psychometric tests. The latency and error data for true and false items are used to develop a general theoretical system that incorporates assumptions about the form of item representation, working memory factors, and processing components and strategies in analogical reasoning tasks.     

Ethical issues in managed care: a Catholic Christian perspective.

A Christian analysis of the moral conflicts that exist among physicians and health care institutions requires a detailed treatment of the ethical issues in managed care. To be viable, managed care, as with any system of health care, must be economically sound and morally defensible. While managed care is per se a morally neutral concept, as it is currently practiced in the United States, it is morally dubious at best, and in many instances is antithetical to a Catholic Christian ethics of health care. The moral status of any system of managed care ought to be judged with respect to its congruence with Gospel teachings about the care of the sick, Papal Encyclicals, and the documents of the Second Vatican Council. In this essay, I look at the important conceptual or definitional issues of managed care, assess these concerns over against the source and content of a Catholic ethic of health care, and outline the necessary moral requirements of any licit system of health care.     

Toward a virtue-based normative ethics for the health professions

Virtue is the most perdurable concept in the history of ethics, which is understandable given the ineradicability of the moral agent in the events of the moral life. Historically, virtue enjoyed normative force as long as the philosophical anthropology and the metaphysics of the good that grounded virtue were viable. That grounding has eroded in both general and medical ethics. If virtue is to be restored to a normative status, its philosophical underpinnings must be reconstructed. Such reconstruction seems unlikely in general ethics, where the possibility of agreement on the good for humans is remote. However, it is a realistic possibility in the professional ethics fo the health professions where agreement on the telos of the healing relationship is more likely to arise. Nevertheless, virtue-based ethics must be related conceptually and normatively to other ethical theories in a comprehensive moral philosophy of the health professions. If he really does think there is no distinction between virtue and vice, why, sir, when he leaves our house, let us count our spoons. Samuel Johnson     

Toward a reconstruction of medical morality

At the center of medical morality is the healing relationship. It is defined by three phenomena: the fact of illness, the act of profession, and the act of medicine. The first puts the patient in a vulnerable and dependent position; it results in an unequal relationship. The second implies a promise to help. The third involves those actions that will lead to a medically competent healing decision. But it must also be good for the patient in the fullest possible sense. The physician cannot fully heal without giving the patient an understanding of alternatives such that he or she can freely arrive—together with the physician—at a decision in keeping with his or her personal morality and values. In today's pluralistic society, universal agreement on moral issues between physicians and patients is no longer possible. Nevertheless, a reconstruction of professional ethics based on a new appreciation of what makes for a true healing relationship between patient and physician is both possible and necessary.     

Cognitive representations of functional interactions with objects

Two studies addressed people’s knowledge about the movements underlying functional interactions with objects, when the interactions were described by simple verbal labels expressing environmental goals. In Experiment 1, subjects rated each action with respect to six dimensions: which portion of the limb moved, distance moved, forcefulness, effectors involved, size of the contact surface, and resemblance to grasp. Ratings were systematic and fell on two distinct underlying factors related to limb movement and effector (usually the hand) configuration. In Experiment 2, subjects sorted a subset of the actions by similarity of movement. Clustering and multidimensional scaling solutions indicated that the six initial dimensions contributed to similarity judgments, along with additional parameters. The results support the existence of cognitively accessible, but still relatively specific, representations of functional actions, with potential implications for motor and memory performance.     

Timecourse of preshaping for functional responses to objects

The present study explores the unfolding of hand shaping the context of functional responding to common objects. The principal issue addressed by this study is whether distinct, identifiable preshapes are evidenced in preparation for four distinct types of hand contact, including nonprehensile as well as prehensile hand shapes, and for small and large surfaces of contact. All four shapes considered here (poke, pinch, palm and clench) showed evidence of distinct preshaping, with similar timecourses in relation to the onset of reaching. The initial separation of the fingers, formation of first identifiable preshape feature, and completion of the preshape appeared at essentially the same time relative tot he onset of reaching for all four hand shapes. The hand shapes did differ, however, in the time between the completion of a stable preshape and contact with the object. The time for preshape-to-contact was greater for hand shapes with small surfaces of contact than for those with large surfaces and for prehensile shapes than for nonprehensile. These differences are attributed to the precision required for the ultimate object-contact response.