人对动物有道德义务吗?

自从10年以前彼得·辛格的《动物解放》一书出版以来,在英国人的书籍中便对动物的道德处境的问题展开了激烈的讨论,在这期间,这个问题也在我们国家引起了较大的重视。从历史上看,这种关心无疑是对于自然的新意识的结果,而这种对于自然的新意识又是由于那些不能再忽视的生态问题产生的。可是按照事情的性质,我们这里所谈的与两个不同的问题有关。适当同自然环境打交道的问题是个我们共同的切身利益的问题,不是一种“生态     

Asymmetries in the regulation of visually guided aiming

An experiment was conducted to examine the contribution of sensory information to asymmetries in manual aiming. Movements were performed in four vision conditions. In the full-vision condition (FV), subjects were afforded vision of both the hand and the target throughout the course of the movement. In the ambient-illumination-off condition (AO), the room lights were extinguished at movement initiation, preventing vision of the moving limb. In the target-off (TO) condition, the target was extinguished upon initiation of the movement. In a no-vision (NV) condition, ambient illumination was removed and the target was extinguished upon initiation of the response movement. Results indicated that accuracy was superior in the full-vision and target-off conditions and when movements were made by the right hand. Movements made by the right hand were also of shorter mean duration. The magnitudes of performance asymmetries were uninfluenced by vision condition. Analyses of movement kinematics revealed that movements made in conditions in which there was vision of the limb exhibited a greater number of discrete modifications of the movement trajectory. On an individual-trial basis, no relationship existed between accuracy and the occurrence of discrete modifications. These data suggest that although vision greatly enhances accuracy, discrete modifications subserved by vision reflect the imposition of nonfunctional zero-order control processes upon continuous higher-order control regimes.     

The stroop effect and the myth of automaticity

A widespread view in cognition is that once acquired through extensive practice, mental skills such as reading are automatic. Lexical and semantic analyses of single words are said to be uncontrollable in the sense that they cannot be prevented. Over the past 60 years, apparently convincing support for this assumption has come from hundreds of experiments in which skilled readers have processed an irrelevant word in the Stroop task despite explicit instructions not to, even when so doing would hurt color identification performance. This basic effect was replicated in two experiments, which also showed that a considerable amount of semantic processing is locally controlled by elements of the task. For example, simply coloring a single letter instead of the whole word eliminated the Stroop effect. This outcome flies in the face of any automaticity account in which specified processes cannot be prevented from being set in motion, but it is consistent with the venerable idea that mental set is a powerful determinant of performance.     

Measurement and mismeasurement of mood: recurrent and emergent issues

The affective explosion in psychology has led to tremendous advances in mood measurement. Mood ratings reflect a hierarchical structure consisting of two broad dimensions-Positive Affect and Negative Affect-and multiple specific states. Brief scales have been developed that reliably assess Positive and Negative Affect across different populations and time frames, in both between- and within-subject data. We examine controversies related to (a) the content of these higher order scales and (b) the independence of Positive and Negative Affect. Regarding the latter, we show that Positive and Negative Affect scales remain largely independent across a wide range of conditions, even after controlling for random and systematic error. Finally, there remains little consensus regarding the lower order structure of affect. This lack of a compelling taxonomy has substantially slowed progress in assessing mood at the specific affect level.     

Of science, meta-science, and clinical practice: the generalization of a generalization to a particular

Although science is the most powerful method for advancing knowledge and scientific and statistical formalisms are generally much sounder than impressionistic judgment, advanced methodological training (as it is presently comprised) is often of little direct use to practicing clinicians. Practitioners should be able to identify grossly deficient knowledge claims and clear scientific winners, but beyond this, the trick usually is to determine which scientific authority or authorities on whom to depend, a decision task that is ultimately to be tackled through the type of meta-scientific studies that Faust and Meehl have proposed. In applying scientific knowledge, the clinician usually must choose between the generalization of a scientific generalization to a particular versus the application of a clinical generalization to a particular. Determining the relative power of scientific generalizations developed outside, versus clinical generalizations developed within the setting of application, can be very difficult, and there are few established guides. A more advanced science of generalization, another meta-scientific problem, would allow sounder predictions about application to new domains and could greatly aid the practitioner.     

Comparing Locomotion With Lever-press Travel In An Operant Simulation Of Foraging

An operant model of foraging was studied. Rats searched for food by pressing on the left lever, the patch, which provided one, two, or eight reinforcers before extinction (i.e., zero reinforcers). Obtaining each reinforcer lowered the probability of receiving another reinforcer, simulating patch depletion. Rats traveled to another patch by pressing the right lever, which restored reinforcer availability to the left lever. Travel requirement changed by varying the probability of reset for presses on the right lever; in one condition, additional locomotion was required. That is, rats ran 260 cm from the left to the right lever, made one response on the right lever, and ran back to a fresh patch on the left lever. Another condition added three hurdles to the 260-cm path. The lever-pressing and simple locomotion conditions generated equivalent travel times. Adding the hurdles produced longer times in patches than did the lever-pressing and simple locomotion requirements. The results contradict some models of optimal foraging but are in keeping with McNair's (1982) optimal giving-up time model and add to the growing body of evidence that different environments may produce different foraging strategies.