In the first experiment, 4 pigeons were each presented with a recurring sequence of four key colors followed by the delivery of grain (block clock). Once the rate of pecking had stabilized, three of the colors were replaced, during different series of sessions, by a darkening of the key. The rate of pecking was reduced within those segments of the interval between deliveries of food during which the key was dark; when the key was dark during the final portion of the interval, rates were reduced throughout the entire interval. In the second experiment, 3 new pigeons were exposed to a different sequence of colors, and the final stimulus was replaced in successive conditions by a novel color, a darkened key, and a restoration of the original color. The data indicated that darkening the key had a more severe, more extensive, and more persistent effect than did a mere change in color. These results suggest that it may be fruitful to conceptualize the autoshaping procedure as a special version of the block clock in which pecking is suppressed throughout the greater part of the interval by darkening the key. In the final condition, the same stimulus appeared in each of the last three portions of the interval. The rate of pecking was lower during the last two portions than when distinctive colors were presented, with the peak rate now appearing in the fifth of seven equal temporal components. 相似文献
177 respondents attending a midwestern state university reported greater alienation from the wider society when they held more positive attitudes than negative ones toward women and homosexuals. Alienation and attitudes toward African-Americans, women, and homosexuals were not influenced by gender or religiosity. 相似文献
Ortony and Turner (1990) asked "What's Basic About Basic Emotions," and they concluded "very little." They proceeded to advocate a "componential" or "mosaic" view of how emotional systems should be analyzed. Their thesis was flawed by their failure to consider the available neurobehavioral data. Genetically dictated brain systems that mediate affective-emotional processes do exist, even though there are bound to be semantic ambiguities in how we speak about these systems. This commentary summarizes key lines of evidence for coherently operating emotional systems in the brain and advocates the position that the issue of basic emotions can no longer be credibly discussed without adequate consideration of the relevant brain research in the area. The type of conceptual, logical analysis pursued by Ortony and Turner, in the absence of a thorough analysis of the available neurological data, is not an adequate basis for resolving what is basic about basic emotions. 相似文献
This article describes further evidence for a new neural network theory of biological motion perception. The theory clarifies why parallel streams V1----V2, V1----MT, and V1----V2----MT exist for static form and motion form processing among the areas V1, V2, and MT of visual cortex. The theory suggests that the static form system (Static BCS) generates emergent boundary segmentations whose outputs are insensitive to direction-of-contrast and to direction-of-motion, whereas the motion form system (Motion BCS) generates emergent boundary segmentations whose outputs are insensitive to direction-of-contrast but sensitive to direction-of-motion. The theory is used to explain classical and recent data about short-range and long-range apparent motion percepts that have not yet been explained by alternative models. These data include beta motion, split motion, gamma motion and reverse-contrast gamma motion, delta motion, and visual inertia. Also included are the transition from group motion to element motion in response to a Ternus display as the interstimulus interval (ISI) decreases; group motion in response to a reverse-contrast Ternus display even at short ISIs; speed-up of motion velocity as interflash distance increases or flash duration decreases; dependence of the transition from element motion to group motion on stimulus duration and size, various classical dependencies between flash duration, spatial separation, ISI, and motion threshold known as Korte's laws; dependence of motion strength on stimulus orientation and spatial frequency; short-range and long-range form-color interactions; and binocular interactions of flashes to different eyes. 相似文献
ALCOVE (attention learning covering map) is a connectionist model of category learning that incorporates an exemplar-based representation (Medin & Schaffer, 1978; Nosofsky, 1986) with error-driven learning (Gluck & Bower, 1988; Rumelhart, Hinton, & Williams, 1986). Alcove selectively attends to relevant stimulus dimensions, is sensitive to correlated dimensions, can account for a form of base-rate neglect, does not suffer catastrophic forgetting, and can exhibit 3-stage (U-shaped) learning of high-frequency exceptions to rules, whereas such effects are not easily accounted for by models using other combinations of representation and learning method. 相似文献
The Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; DSM-III-R) operationally defines disorder essentially as "statistically unexpectable distress or disability." This definition is an attempt to operationalize 2 basic principles: that a disorder is harmful and that a disorder is a dysfunction (i.e., an inability of some internal mechanism to perform its natural function). However, the definition fails to capture the idea of "dysfunction" and so fails to validly distinguish disorders from nondisorders, leading to invalidities in many of DSM-III-R's specific diagnostic criteria. These problems with validity are traced to DSM-III-R's strategies for increasing reliability. 相似文献
The effects of varying decision outcome dispersion on organizational decision making were investigated under individual and group decision making conditions. Thirty-six female and pg]36 male subjects made decisions for organizational decision scenarios in which outcomes affected primarily the decision maker, people other than the decision maker, or a group of which the decision maker was a member. Subjects rated their levels of perceived risk and confidence in their decisions and made decisions within a simulated context of either a small or a large organization. Results indicated that subjects perceived significantly less risk and more confidence in their decisions when outcomes affected primarily themselves rather than others regardless of whether the decisions were made individually or by a group. Males perceived their decisions as significantly more risky than females. Induced organizational size did not significantly influence decision making.
This study was done to assess gender and cultural differences on neuroticism as a dimension of personality among both Canadians and Black South Africans. No statistically significant cross-cultural differences were observed. However, statistically significant gender differences emerged among both Canadian and African men and women, with the latter scoring higher on neuroticism than the former. 相似文献