Development of differences in response latencies to right and left visual fields

Robust lateralization developed in right-handed adults who were asked to judge letter pairs as "same" or "different" during 4608 trials. By the end of the first two blocks (768 trials) "same" responses were favored when presented in the RVF (transmitted directly to the left hemisphere) and "different" responses were favored when presented in the LVF (transmitted direction to the right hemisphere). This gradually reversed over sessions with "same" responses becoming faster for letters presented in the LVF, and "different" responses becoming faster for stimuli presented in the RVF. The laterality acquired under these conditions was cumulative and reproducible, appeared in all 16 subjects, and was preserved between sessions a week apart. The data suggest that laterality is a flexible and reversible characteristic of the human brain even when stimulus and task remain constant.     

Acquisition and retention of gestures by apraxic patients

The purpose of this study was to examine whether apraxic-aphasic patients with parietal lesions had difficulty learning lists of gestures and whether the performance deficits they displayed resulted from an inability either to consolidate this information in memory or to retrieve the information once stored. The findings indicate that apraxic-aphasic patients do have difficulty acquiring lists of gestures. This inability to reproduce gestural information was not associated with a retrieval disorder, but instead the apraxic-aphasic subjects could not consolidate the information in memory.     

The effects of recency and story content on children's moral judgments

Sixteen stories were read to children at ages 4, 7, and 11 years and to college freshmen (n = 24 per age level) to investigate the effects of recency and specific story content on the development of moral reasoning. The stories consisted of either positive or negative intention and either positive or negative consequence in one of four situations: rule breaking, property damage, property damage with peer interaction, or injury to a person. At each age level, half of the subjects heard the stories with the intention first and the consequence second, and half heard them in the reverse order. Analyses confirmed that in general younger children judged on consequence, whereas older children utilized intention, and that on stories containing intentional injury to a person, the younger child took intention into account. Recency effects were evidenced for both the 4- and 7-year-olds. In the 4-year-old group, however, the recency effects failed to override the salience of negative consequence in contexts of positive intention and negative consequence. This suggests that preschool children may respond primarily to the negative aspect of the story, whether intention or consequence.     

Infant sensitivity to figural coherence in biomechanical motions

Two experiments assessed infant sensitivity to figural coherence in point-light displays moving as if attached to the major joints of a walking person. Experiment 1 tested whether 3- and 5-month-old infants could discriminate between upright and inverted versions of the walker in both moving and static displays. Using an infant-control habituation paradigm, it was found that both ages discriminated the moving but not the static displays. Experiment 2 was designed to clarify whether or not structural invariants were extracted from these displays. The results revealed that (1) moving point-light displays with equivalent motions but different topographic relations were discriminated while (2) static versions were not, and (3) arrays that varied in the amount of motion present in different portions of the display were also not discriminated. These results are interpreted as indicating that young infants are sensitive to figural coherence in displays of biomechanical motion.     

Selective association learning in the rat: Generality of response system

Three experiments with rats examined the possibility that the cue-consequence specificity effect is not mediated by the conditioning of selective associations, but instead reflects the selective behavioral expression of taste-illness and exteroceptive-shock conditioning. Experiment 1 showed that the selective aversion performance could be obtained despite the use of locomotor withdrawal from the CS as the index of conditioning. Experiment 2 compared the response profiles of animals conditioned with footshock or illness to presentation of a saccharin or noise CS. During the test with the noise CS, lithium-conditioned subjects did not differ from control rats on any of several behavioral categories, but shock-conditioned rats showed high levels of freezing in response to the noise cue. During the saccharin test, lithium-treated rats engaged in behaviors such as chin wiping, head shaking, and gaping; these behaviors were rarely or never seen in shock-conditioned rats or controls, whose behavioral profiles during the saccharin test were almost identical. Experiment 3, using a blocking design, found that a noise-lithium pairing did not attenuate subsequent conditioning of a saline-lithium association, nor did a saccharin-shock pairing interfere with conditioning of a noise-shock association. These results confirm that the cue-consequence specificity effect is mediated by the selective associability of taste with illness and of exteroceptive cues with footshock.     

医学伦理学概念之探究

医学伦理学的概念看起来很简单,一般情况下人们便习以为常地接受了作为应用规范伦理学的一个分支的科学地位,而忽视了医学对医学伦理学所起的作用。本文认为：医学伦理学的具体内容是医学科技与伦理道德两因素相互作用的产物,对其相互作用的形式和产物的具体分析和总结便可构成这门学科的理论体系。     

New directions for the education of clinical psychologists: The primary care setting,the VA's PRIME program,and the in-depth generalist model

As part of this special issue on psychology in primary care settings, we describe the Department of Veterans Affairs' (VA's) new approach to education for practice in the primary care setting and we concurrently address some general issues related to the education of clinical psychologists for practice in this setting. In this article we argue that the primary care psychologist, in parallel with the generalist in medicine, must have a strong generic background in clinical psychology in order to gain the broad range of clinical skills necessary to function effectively as an in-depth generalist (IDG) who is capable of addressing the variety of psychological issues that emerge in the primary care setting. The IDG model of professional practice, which we believe is best suited for primary care/managed care settings, requires extensive training in generic clinical skills and increased time devoted to its implementation at both the predoctoral and the postdoctoral levels.     

A signal detection framework for the evaluation of probabilistic forecasts

In this paper I formulate an approach for evaluating probabilistic forecasts in terms of signal detection theory. Signal detection theory provides a powerful perspective for this type of problem, and a rich empirical background including methodological tools as well as an extensive body of research in many domains. I propose procedures which emphasize the maximization of expected utility for the decision maker who uses the forecasts. Further, I suggest approaches to obtaining indices of calibration and resolution within this framework. I also present arguments that the proposed indices will exhibit the same basic properties as do decompositions of Brier's (1950, Monthly Weather Review, 78, 1–3) mean probability score. However, the properties may be reflected in different ways, and hence, the present methods may lead to different conclusions about forecasting ability. Finally, I argue that the use of an expected utility loss function makes this approach more appropriate for practical applications as well as for theoretical research than other procedures with more arbitrary loss functions.     

The effects of feedback consistency and feedback favorability on self-perceived task competence and perceived feedback accuracy

The present study, employing a 2 × 2 true-experimental design and regression analyses assessed the main and interactive effects of feedback consistency (consistent vs inconsistent), and feedback favorability (acceptable vs superior), for feedback given at two time periods on measures of perceived feedback accuracy and self-perceived task competence. Among the study's findings were that (a) the perceived accuracy of feedback at the second period was a function of the favorability of feedback received at the first time period, (b) the self-perceived task competence levels of subjects were jointly determined by the favorability of feedback received at both time periods, and (c) the perceived accuracy of feedback was a function of its consistency. Organizational implications of the study's results are offered.     

On optimal smoothing and derivative estimation from noisy displacement data in biomechanics

Estimating derivatives from noisy displacement data is a notoriously ill-posed problem in signal processing and biomechanics. Following the work of Wood and Jennings (1978) and Hatze (1979, 1981), the present paper describes the use of optimally regularized, natural quintic splines for estimating smoothed positions, velocities, and accelerations from equidistantly sampled, noisy position measurements. It appears that the nature of the boundary conditions of the data is of some importance, since various algorithms used hitherto result in artefacts throughout the data if the true derivatives at the record ends differ significantly from zero. Natural quintic splines do not suffer from this disadvantage below the third derivative.The ill-posed character of movement analysis has some interesting implications for movement synthesis and optimization, similar to the indeterminacy of muscular co-contraction from merely external, biomechanical measurements.