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1.
本实验是以异色亮度匹配方法,探索视觉系统对在明视觉水平上的低频、不同时间调制的单色光和白光的亮度感觉特性。结果发现,闪光刺激在临界频率以上作用于视觉系统所产生的亮度感觉是遵循塔耳玻特-普拉托定律。而对在临界频率以下亮暗比为4/1的间断单色光刺激所需的周期平均亮度低于恒定单色光所需的亮度幅度,这表明塔耳玻特(Talbort)定律不适用于低频、高亮暗比的间断单色光。仅适用于间断单色光刺激的亮暗比低于1,波长为650纳米的间断单色光。  相似文献   

2.
Pigeons key pecked for grain on a fixed-ratio 100 schedule; electric shocks occurred intermittently at the fifteenth or eighty-fifth response in the ratio. In Experiment I, shock was at the fifteenth response for two birds, and at the eighty-fifth response for two others, in every sixth, twelfth, or eighteenth ratio. Rate of responding decreased as frequency of shock increased, and the pattern of responding included an increased initial pause and low rates or pause-run sequences that extended further into the ratio when shock was at the fifteenth response than when it was at the eighty-fifth response. Shock early in the ratio engendered longer initial pauses than shock late in the ratio. In Experiment II, four birds responded on a two-component multiple schedule in which shock occurred at the fifteenth response of the third ratio in the presence of a white keylight and at the eighty-fifth response of the third ratio in the presence of a green keylight. The overall rates of responding decreased as shock intensity increased. All four birds responded differentially to the white and green keylights, but with a pattern that varied between birds. In general, punishment reduced the probability of responses that preceded it, regardless of the ordinal position of those responses. Both studies confirm that the probability of responding is reduced less by aversive stimuli produced late in a fixed-ratio than by aversive stimuli produced early in a fixed-ratio.  相似文献   

3.
Abstract: Six undergraduates were exposed to a fixed‐ratio schedule with an instruction to respond slowly and to a differential‐reinforcement‐of‐low‐rate schedule with an instruction to respond rapidly when a white circle was presented on a display monitor. When a yellow circle was presented, however, the subjects were exposed to the fixed‐ratio schedule with the instruction to respond rapidly and to the differential‐reinforcement‐of‐low‐rate schedule with the instruction to respond slowly. Following this, a fixed‐interval schedule was in effect during those stimuli and instructions. Under the white circle, response rates were higher with the instruction to respond slowly than with the instruction to respond rapidly during the fixed‐interval schedule. Such control by instructions was not observed under the yellow circle. A previous study examined establishment of novel instructional control by between‐subject comparisons and found that for three of four subjects ( Okouchi, 1999 ). In contrast, the present results demonstrate the instructional control through within‐subject comparisons for all six subjects.  相似文献   

4.
In White's display the gray target surrounded more by black than white appears darker than the target of the same physical luminance surrounded more by white than black. Several subsequent studies have shown that this effect occurs only when the luminance of the test regions lies between the minimum and maximum luminance values of the inducing stripes. With targets either lighter or darker than both inducing stripes, the direction of the effect is reversed and the effect is known as the 'inverted' White's effect. Views differ on whether the classical and inverted White's effects are mediated by common or separate underlying mechanisms. We varied the aspect ratio of the test and inducing regions in the classical and inverted White's effects. Consistent with previously reported findings, we found that the direction of the classical effect did not depend on the amount of black or white border in immediate contact with the test patch. On the other hand, perceived lightness in the inverted White's effect was affected by such variations, suggesting that induction in classical and inverted White's configurations is governed by different mechanisms. These results confirm the critical importance of the interaction between luminance and geometric relationships in induced brightness.  相似文献   

5.
Chained concurrent schedules: reinforcement as situation transition   总被引:7,自引:7,他引:0       下载免费PDF全文
Pigeons' pecks at two white response keys (initial-link situation) occasionally turned both keys red (terminal-link situation). When the two keys were red, pecks occasionally produced food, after which the keys were again white. In both situations, a changeover delay prevented the response-produced outcome from immediately following a change of responding from either key to the other. In the initial-link situation, the ratio of pecks at the keys closely paralleled the ratio of transitions into the terminal-link situation produced by the pecks, conforming to the well-known matching relation. In the terminal-link situation, the peck ratios deviated from the matching relation toward indifference. Overall response rate and rate of changeover were generally higher in the terminal-link situation than in the initial-link situation. The finding of matching in the initial-link situation supports a definition of reinforcement as situation transition. The differences in performance between the two situations, viewed in the light of other recent findings, suggest that the effects of a changeover delay depend on the overall reinforcing value of the choice alternatives.  相似文献   

6.
This exploratory study investigated the relationship between two measures of perceptual-motor problems. Ratios derived from the Object Assembly subtest of the WISC with errors greater than 1 SD on the Bender test using Koppitz' scoring system were compared. The sample of 66 white middle-class children was 6 to 11 yr. old. The particular ratio studied was statistically significantly associated with the Bender, whereas ratios of other Object Assembly items were not. The Horse ratio was also significantly associated with the presence of learning problems shown in children's files.  相似文献   

7.
Pigeons were exposed to a concurrent-chains schedule in which a single variable-interval 30-s schedule was used in the initial links and fixed-time schedules were used in the terminal links. Three types of keylight conditions were used in the terminal links. In the first condition, different delays were associated with different keylight stimuli (cued condition). In the second condition, different delays were associated with the same stimulus, either a blackout (uncued blackout condition) or a white key (uncued white condition). Paired values of terminal-link fixed-time schedules differed by a constant ratio of 3:1, while the absolute value of delays was varied from 3 s to 54 s. The results showed that choice proportions for the shorter of two delays increased when the absolute size of the delays was increased for all keylight conditions. Further, the choice proportions for the shorter delay increased from the uncued blackout condition, to the uncued white condition, to the cued condition. A modified version of Fantino's (1969) delay-reduction model (expressed as a function relating the response ratio to the delay-reduction ratio) can be applied to these data by showing that sensitivity to delay reduction increased from the uncued blackout condition, to the uncued white condition, to the cued condition. Thus, the present study demonstrated that a modified version of the delay-reduction model can be used to assess quantitative differences in the terminal-link keylight condition in terms of sensitivity to delay reduction (i.e., the conditioned reinforcing value of the terminal-link keylight stimuli).  相似文献   

8.
With .2-sec bursts of white noise as both conditioned stimulus (CS) and unconditioned stimulus (UCS), conditioning of first-interval skin conductance responses was obtained when the intensity of the CS equaled and exceeded that of the UCS. There was no evidence that second-interval response conditioning occurred. Nonspecific response frequencies were also affected by the variations in stimulus intensity, this raising some question about typical controls employed in SCR conditioning. There was some evidence that second interval responses were suppressed by the intense CS values. It was concluded that the existence of simple conditioning with a CS/UCS intensity ratio equal to or greater than unity was contrary to the Pavlovian proposition that a CS must be biologically less salient than the UCS in order for conditioning to occur. It was noted, however, that the suppression of second-interval responses might indicate that anticipatory CRs which are not confounded with orienting reflexes are prevented from exhibiting a conditioning effect when a high CS/UCS intensity ratio is employed.  相似文献   

9.
Children of 3, 5, and 8 years of age were trained on a temporal bisection task where visual stimuli in the form of blue circles of 200 and 800 ms or 400 and 1600 ms duration, preceded by a 5-s white circle, served as the short and long standards. Following discrimination training between the standards, stimuli in the ranges 200-800 ms or 400-1600 ms were presented with the white circle either constant or flickering. Relative to the constant white circle, the flicker (1) increased the proportion of "long" responses (responses appropriate to the long standard), (2) shifted the psychophysical functions to the left, (3) decreased bisection point values, at all ages, and (4) did not systematically affect measures of temporal sensitivity, such as difference limen and Weber ratio. The results were consistent with the idea that the repetitive flicker had increased the speed of the pacemaker of an internal clock in children as young as 3 years. The "pacemaker speed" interpretation of the results was further strengthened by a greater effect of flicker in the 400/1600-ms condition than in the 200/800-ms condition.  相似文献   

10.
Miller  R. J. 《Sex roles》2001,44(3-4):209-225
Two experiments explored factors related to gender differences in Ponzo illusion susceptibility. In Experiment 1, 54 male and 54 female (predominantly white, middle class) undergraduates were administered Witkin's Embedded Figures Test (EFT) and, on 2 separate occasions, a form of the Ponzo illusion. Results showed the Ponzo to be quite reliable over several days. Females were significantly more field dependent (as shown by slower responses to the EFT), and significantly more susceptible to the Ponzo illusion, than males. Furthermore, EFT performance correlated significantly with Ponzo susceptibility for females, but not for males, suggesting that the difference between males and females in Ponzo response may be due not to differences in field independence per se, but rather to differences in the strategies used to solve the illusion task. In Experiment 2, 111 male and 148 female (predominantly white, middle class) undergraduates were administered the Ponzo illusion twice, the 2 administrations separated by about 90 min. Again, the illusion task showed good reliability, and females were significantly more susceptible to the illusion. Furthermore, the magnitude of the difference between males and females was systematically related to the sex ratio (the ratio of the number of males to the number of females) of the particular session in which each subject happened to be participating. It is suggested that social factors such as sex ratio might affect the strategies participants use when doing illusion tasks, and perhaps other spatial skills tasks as well.  相似文献   

11.
12.
This research project studied the educational preferences of older adults in 22 churches in North Carolina. These older adults displayed a significant preference for "instrumental" activities over "expressive" activities. Level of education and occupation (or previous occupation) were significantly related to educational preference. Persons with fewer years of schooling indicated significant preference for instrumental activities, almost to the exclusion of expressive interests. As levels of education rose, there was a decrease in the ratio of instrumental preferences to expressive preferences. Persons in white collar jobs preferred expressive learning experiences more than blue collar individuals. Programming implications for local churches are discussed.  相似文献   

13.
Little is known about deaths resulting from self-inflicted violent behavior for Hispanic Americans. To learn more about suicide for Hispanics of Mexican origin (Mexican Americans) we focused on the five southwestern states (Arizona, California, Colorado, New Mexico, and Texas) in which more than 60% of all Hispanics in the United States reside (86% of whom are Mexican American). We obtained data on the number of suicide deaths in the white population, with Hispanics and Anglos (white, non-Hispanic) identified separately. Suicides of Anglos were used as a comparison group. Results show that the suicide rate for whites in the five southwestern states (15.6) was almost one-fourth higher than the rate for whites nationally (12.7). Suicide rates for the two ethnic groups, however, showed the rate for Hispanics (9.0) to be less than the national rates for whites (12.7) and one-half that of Anglos residing in the same area (17.3). The lower suicide rate for Hispanics relative to Anglos is seen for both males and females. The ratio of male and female suicides for Hispanics was almost twice that for Anglos (4.0 to 1 for Hispanics and 2.3 to 1 for Anglos). More than 1 in 3 Hispanic men who committed suicide and more than 1 in 4 Hispanic women who committed suicide are under the age of 25.  相似文献   

14.
The generality of the mathematical principles of reinforcement (MPR) was tested with humans. In Experiment 1A, participants’ mouse clicks were reinforced according to a series of variable-ratio (VR) values. In one condition, a situated task was used (searching for treasure on a map presented via a PC monitor); in the other, abstract version of the task, participants clicked on a white screen. Under the “map” condition, response rates increased with increasing ratio value before decreasing with further ratio increases; under the “no-map” condition, response rates decreased linearly from a peak at the smallest ratio. In Experiment 1B, the pattern of responding was confirmed under the “map” conditions using a different set of ratio values. In Experiment 2, reinforcer magnitude was manipulated using the “map” context. Response rates did not differ significantly when large rather than small cash reinforcers were delivered according to a VR 30 but were significantly higher when large rather than small cash reinforcers were delivered according to a VR 120. Together these experiments offer qualified support for extending MPR to the behavior of human participants.  相似文献   

15.
文化差异影响彝、白、纳西和汉族大学生对黑白的认知   总被引:3,自引:0,他引:3  
以彝族、白族、纳西族和汉族的大学生为被试,采用颜色相似性判断和颜色再认任务,考察了彝族、白族、纳西族和汉族的大学生对于黑色和白色的认知,意在探究不同民族的黑、白文化是否影响人们对黑、白颜色的认知。结果发现:⑴彝族、白族、纳西族和汉族的黑、白文化影响四个民族的大学生对于黑色和白色的认知;⑵语言和文化对于颜色认知的影响包括间接效应和直接效应。整个研究表明,语言和文化对颜色认知有重要影响  相似文献   

16.
Further to the debate between Kearins (1978) and Drinkwater (1978), visual memory skills of Aboriginal and white Australian children were examined using Drinkwater's version of Kim's game with desert Aboriginal and rural white children. Older children remembered more than younger ones, and Aboriginal children recalled more natural objects than white children. There was no difference between the groups in recall of manufactured objects, nor between recall of manufactured and natural objects within each group. Aboriginal children remembered significantly more objects overall than white children when the task was first administered. On a second occasion, after a procedure designed to orient children towards the use of predominantly visual rather than verbal memorising strategies, there was no significant difference between the groups.  相似文献   

17.
Seventy-two white undergraduates of both sexes taught a lesson “What is psychology?” to a 10-year-old male confederate. Four confederates, two white and two black, alternated in the three conditions of induced expectancy: Subjects were told the child was bright, dull, or were given no information. Unknown to subjects, their nonverbal behavior during the lesson was videotape recorded. Results indicated that induced expectancy affected subject nonverbal behavior only when the confederate was white. Subjects smiled more, looked more, and nodded more at the white “bright” confederates than the white control or “dull” confederates. However, expectancy had no effect, positive or negative, when the confederate was black. In addition, white confederates received more positive nonverbal behavior overall than did black confederates.  相似文献   

18.
Delayed and current stimulus control in successive discriminations   总被引:1,自引:1,他引:0       下载免费PDF全文
In a successive discrimination in which successively alternating red and green hues signaled component variable-interval schedules, sensitivity of the ratio of responses in the two components to variation in the component reinforcer ratio decreased systematically during the course of the component. This decrease in stimulus control or discrimination over the course of the component was shown to be the result of delayed control of responding during the component by the stimulus transition between components. When the red–green stimulus transition was altered by interpolating a white stimulus at the end of each 60-s component, discrimination at the beginning of the component (measured by the power-function exponent for sensitivity to reinforcement) was reduced. Conditions with the white stimulus inserted in other quarters of the component indicated that the current discriminative stimulus exerts control over responding throughout the component, whereas during about the first half of the component, response differentials are influenced by the transition between discriminative stimuli.  相似文献   

19.
J. Brian Pitts 《Synthese》2013,190(12):2117-2139
It is widely believed that one should not become more confident that all swans are white and all lions are brave simply by observing white swans. Irrelevant conjunction or “tacking” of a theory onto another is often thought problematic for Bayesianism, especially given the ratio measure of confirmation considered here. It is recalled that the irrelevant conjunct is not confirmed at all. Using the ratio measure, the irrelevant conjunction is confirmed to the same degree as the relevant conjunct, which, it is argued, is ideal: the irrelevant conjunct is irrelevant. Because the past’s really having been as it now appears to have been is an irrelevant conjunct, present evidence confirms theories about past events only insofar as irrelevant conjunctions are confirmed. Hence the ideal of not confirming irrelevant conjunctions would imply that historical claims are not confirmed. Confirmation measures partially realizing that ideal make the confirmation of historical claims by present evidence depend strongly on the (presumably subjective) degree of belief in the irrelevant conjunct. The unusually good behavior of the ratio measure has a bearing on the problem of measure sensitivity. For non-statistical hypotheses, Bayes’ theorem yields a fractional linear transformation in the prior probability, not a linear rescaling, so even the ratio measure arguably does not aptly measure confirmation in such cases.  相似文献   

20.
This study assessed the effects of gender, race, and social class on the general and area-specific self-esteem of high school students. One hundred and ninety-five high school students served as subjects in a 2 (gender: male, female) X 2 (race: black, white) X 3 (social class: low, middle and high) factorial design. The Rosenberg General Self-Esteem, the Piers-Harris Children's Self-Concept, and the Brookover Self-Concept of Ability and School Achievement scales were the measures of either general or specific self-esteem. Females, whites, and lower social class adolescents were consistently lower in their self-esteem scores than were males, blacks, and upper social class teenagers, respectively. White females were found to be lower in general and happiness self-esteem than all other gender by race subgroups. High SES white students were lower on the happiness and behavior self-esteem measures than black students and white middle-class students. Black males and white females were less confident in their school ability than were black females and white males.  相似文献   

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