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1.
Rats were permitted to control, by means of a changeover response, the amount of time spent in either a “differentiated” or an “undifferentiated” condition. Shock occurred in both conditions on the same variable-time schedule, half of the shocks being short (.75 sec) in duration, the other half, long (5 sec). In the differentiated (informative) condition, all short shocks were preceded by one signal and all long shocks were preceded by a discriminatively different signal. No information about shock duration was available in the undifferentiated condition, as the same signal preceded short and long shocks. A clear and consistent preference emerged for the differentiated condition, i.e., for information about shock duration. The relevance of this finding for theories which attempt to account for the preference-for-signaled-shock phenomenon was discussed.  相似文献   

2.
In previous studies of anticipatory contrast, identical target components (A and B) preceded either a lower (extinction) or a richer schedule. Higher response rates occurred during the target preceding the lower rate of reinforcement, whereas preference was in favor of the target preceding the richer schedule. In Experiment 1, the response and preference measures were positively related when additional stimuli, with no reinforcement of their own, preceded the target components. The effect of these additional stimuli was presumed to be due to their overshadowing of the Pavlovian association between the target components and their following schedules. Experiment 2 also demonstrated a consistent relation between response rate and preference in a conditioned reinforcement procedure. In the absence of a strong Pavlovian association, anticipatory contrast, like other forms of contrast in free-operant procedures, reflects an increase in the value of the target component with an unchanged reinforcement schedule.  相似文献   

3.
Rats were trained in the discrete-trial operant apparatus with single alternation of large reward and small reward or large reward and nonreward. followed by either transfer or extinction. The results showed that both groups acquired appropriate response patterning, that patterning is conditioned, and that the stimuli which control patterning are derived from reward conditions on immediately preceding trials. A modification of the sequential hypothesis of instrumental learning was proposed to account for the results.  相似文献   

4.
In Experiment 1, four groups of rats were initially trained on a discrimination which established a stimulus as a signal for reinforcement. That signal was then presented during subsequent partial reinforcement training in a way that could potentially interfere with retrieval of the memory of nonreinforcement (SN) on the preceding trial either because (1) thestorage and retrieval contexts for SN were different (retrieval failure hypothesis), or (2) the memory of reinforcement produced by the signal acted as a competing memory (competing memory hypothesis). Experiment 1 supported the competing memory hypothesis. In Experiment 2, we investigated the effect of stimulus change on the capacity of the context to retrieve a competing memory of a temporally remote reinforcement event with which the context was strongly associated. Retrieval of a competing memory was impaired by differences between the storage and retrieval contexts in a manner analogous to the effect of context on retrieval of a reinforcement event memory from an immediately preceding trial.  相似文献   

5.
Acquisition of both signaled and unsignaled operant avoidance learning was studied in 64 rats as a function of shock intensity, with three different warning signals used in the signaled procedure. In both signaled and unsignaled avoidance, overall response rate was a progressively increasing function of shock intensity. This was due to both an absolute and relative increase in the frequency of responses at shorter interresponse times with increasing shock intensity. Presence of an effective warning signal in the interval immediately preceding shock increased the probability of an avoidance response in this interval, decreased overall response rate, and reduced shock frequency. A buzzer signal proved most effective, followed by tone and light. However, once a warning signal occurred, the probability of an avoidance response to the signal was virtually independent of shock intensity. Also, an index of avoidance efficiency proved to be inversely related to shock intensity.  相似文献   

6.
In two studies, the author investigated interactions among adjunct question position, reading ability, and direct versus indirect learning outcomes for deaf postsecondary and hearing middle-school students. Adjunct questions were inserted immediately preceding or following brief sections of instructional prose for the purpose of focusing and cognitively activating the readers. Different effects were observed for deaf and hearing readers and for different levels of assessed reading ability. The findings are discussed in terms of reading ability, adjunct activities while reading prose, and direct versus indirect instructive effects.  相似文献   

7.
Cognitive preference, a cognitive style acquired through life and learning experiences and representing a distinct orientation to the processing of information, is related to creativity in this study. Significant correlations were observed between cognitive preference and verbal creativity but not with figural creativity as measured by the Torrance Test of Creative Thinking.  相似文献   

8.
Five experiments investigated the reliability of, and a possible explanation for, the preference for signaled shock (PSS) phenomenon, in which animals show a preference for signaled over unsignaled, unmodifiable shock. Experiment 1 demonstrated the generality of our previous PSS shuttlebox data. In an attempt to explain some of the studies in which a failure to obtain a PSS has been reported, Experiments 2 and 3 found that under certain conditions the PSS effect could be overridden by an innate preference for dark; however, the series of experiments in toto speaks clearly for the robustness of the phenomenon. Consistent with the recently proposed “crossover consequence hypothesis,” Experiments also revealed that shuttling behavior during manifestations of PSS is not randomly distributed in time. However, Experiments 4 and 5 found that PSS could not generally be attributed to an interaction between the acquired aversiveness of the signal and the spatially asymmetrical probability of shuttling being punished, as proposed by this hypothesis.  相似文献   

9.
关联理论的语境观   总被引:1,自引:1,他引:0  
关联理论的语境观不仅仅局限于现实环境中的情景或话语本身的语境,还包括人们对世界的一系列假设,关联理论中的语境是认知性质的,即认知语境。认知语境是在话语理解过程中不断选择的结果,而不是在理解话语之前事先给定的。对语篇的理解不仅要依赖上下文语言语境,而且更要依赖人的认知语境,这样才能有效地理解话语,有效地减少篇章阅读中生词的困扰。  相似文献   

10.
Manipulating experience with the reinforcer, through either home cage presentations of Noyes pellets or availability of the free reinforcer immediately prior to testing, attenuated the preference for earned as opposed to free reinforcers. Similarly, changing the reinforcer to one of a different flavor at testing increased the preference for the noncontingent reinforcer. These results are consistent with an interpretation of earned reinforcer preference which emphasizes the role of the reinforcer as a discriminative signal for further instrumental responding. It is suggested that the tendency to perform instrumental responses for reinforcers when free reinforcers are available can be explained in terms of traditional learning processes.  相似文献   

11.
Pigeons were trained in an intratrial interference preparation in which a horizontal or vertical line was presented for 1 sec immediately following termination of a sample (red or green). Two samples were presented successively on interference trials. Choice of the comparison corresponding to the second (target) sample was designated correct and was reinforced, and choice of the comparison corresponding to the first (interfering) sample was designated incorrect and was not reinforced. Control trials involved the presentation of a single, target sample. A horizontal line was presented upon termination of an interfering sample, and a vertical line was presented upon termination of a target sample. The results of three experiments led to the conclusion that the horizontal line acquired and capacity to reduce postperceptual processing (rehearsal) of information derived from an immediately preceding sample stimulus. These findings include (1) convergence of accuracy on control and interference trials as training progressed, (2) a reduction in accuracy on control and especially on interference trials when the correlation between sample type (interfering or target) and cue type (horizontal or vertical) was reduced to zero, (3) higher accuracy (i.e., less interference) when the horizontal rather than the vertical line followed the interfering sample, and (4) higher accuracy on single-sample trials when the vertical rather than the horizontal line followed sample presentation.  相似文献   

12.
Previous place conditioning studies in mice have shown that injection of ethanol immediately before a conditioned stimulus (CS+) produces conditioned preference, whereas injection of ethanol immediately after CS+ produces conditioned aversion. In the present experiments, we examined the learning that occurs when ethanol is injected in “ambiguous“ procedures that provide the opportunity for both types of conditioning. When ethanol was given midway through the CS (Experiments 1 and 2) or both before and after the CS (Experiment 3), the direction of place conditioning was the same as when mice were exposed only to whichever contingency occurred first (a primacy effect). That is, injection of ethanol in the middle of the CS conditioned aversion, whereas injection both before and after the CS conditioned preference. Because these results support the idea that ethanol elicits both aversive and rewarding effects, they are most consistent with conditioning theories that conceptualize unconditioned stimuli (USs) as events that can activate multiple representational components.  相似文献   

13.
Drugs of abuse have both rewarding and aversive effects, as indexed by the fact that they support place preferences and taste aversions, respectively. In the present study, we explored whether having a history with the aversive effects of morphine (via taste aversion conditioning) impacted the subsequent rewarding effects of morphine, as measured in the place preference design. In Experiment 1, rats were exposed to a taste aversion procedure in which saccharin was followed by morphine. Place preference conditioning was then initiated in which animals were injected with morphine and placed on one side of a two-chambered apparatus. Animals with a taste aversion history acquired place preferences to the same degree as controls without such a history, suggesting that morphine’s affective properties condition multiple effects, dependent on the specific stimuli present during conditioning. To determine whether these results were a reflection of processes operating in traditional associative conditioning, in a modified blocking procedure, place preference conditioning was attempted in the presence of a taste previously associated with morphine (Exp. 2). Under these conditions, animals still acquired morphine-induced place preferences comparable to those of animals without a morphine or conditioning history. These results are consistent with the position that drugs of abuse have multiple stimulus effects (positive and negative) that are differentially associated with specific stimuli (environmental and taste) that drive different behavioral responses (approach and avoidance).  相似文献   

14.
Seventy male hooded rats received single-alternation runway training in which goalbox placements were interpolated during the 20-sec intertrial interval. Placements provided alternating reward/ nonreward, random reward/nonreward, continuous reward, or continuous nonreward. Relative to nonplaced controls, alternation performance was reliably facilitated only by intertrial alternation placements which re-presented the goal event of each immediately preceding instrumental trial. All other intertrial procedures reliably impaired alternation performance. Degree of impairment was graded from least to most as follows: intertrial alternation placements with the goal event opposite to that of each immediately preceding instrumental trial, intertrial placements with continuous non-reward, intertrial placements with continuous reward, and intertrial placements with random reward/nonreward.  相似文献   

15.
It has been reported previously that rats prefer a flavor they consumed under high deprivation to a flavor they consumed under low deprivation (Revusky, 1967). Here it was found that this preference occurs only if nutritive solutions are used and the flavors are given preceding and following eating. If flavors are given separately from the daily feeding, rats prefer the flavor given under low deprivation, whether or not a nutritive solution is used (Experiment 3). If flavors are given before and after the daily feeding, rats prefer the flavor they had under high deprivation (before feeding) more if sucrose solutions are used than if saccharin solutions are used and more on a high-deprivation test than on a low-deprivation test (Experiments 1 and 2). It was concluded that the “incentive value” of consumption is not necessarily higher under high deprivation than under low deprivation. The preference for the low-deprivation flavor obtained here may reflect a greater proportional rewarding effect of consumption under low deprivation or may reflect an aversion to the flavor consumed under high deprivation. Perhaps a small taste of flavor under high deprivation initiates responses of digestion that are unsatisfied and thus aversive, and the more so the higher the deprivation level.  相似文献   

16.
价值澄清理论与大学生思想政治教育   总被引:6,自引:0,他引:6  
价值澄清理论是20世纪美国最有影响的道德教育理论流派之一.针对多元价值观的影响,该理论强调道德或价值观不是靠教导获得的,而是经过自由选择、珍视和行动澄清出来的.价值澄清理论对当前大学生思想政治教育有着重要的启示意义.  相似文献   

17.
The ability of visual CSs previously paired with flavored substances to substitute for those substances as conditional discriminative cues was examined in two Pavlovian appetitive conditioning experiments using rat subjects. In Experiment 1, a visual stimulus was first paired with the delivery of a sucrose solution. Then the rats were trained in conditional discrimination tasks in which sucrose delivery alone served as a conditional cue signaling whether or not a subsequent tone would be reinforced with food pellets. Subjects rapidly acquired discriminative performance to the tones, especially in a feature-negative condition in which sucrose delivery signaled when the tone would not be reinforced. In a subsequent test in which neither food nor sucrose was delivered, presentation of the visual CS also controlled discriminative performance to subsequently presented tones. Experiment 2 showed the ability of a visual CS to substitute for a flavored substance as a conditional cue to be highly stimulus specific. Experiment 2 also showed that a flavored substance was less effective as a conditional cue when it was made to be expected by preceding it with a previously associated visual signal than when it was made to be surprising by preceding it with a visual stimulus signaling another flavored liquid. These results indicate that CS-evoked representations of events can substitute for those events themselves in the control of previously established conditional discrimination performance.  相似文献   

18.
介绍以AT89S51单片机为核心的多功能自动拨号报警系统,给出了系统硬件框图和程序流程图.该系统能够进行电话线的断线检测,能够任意修改预设电话号码,能通过无线方式准确接收到并区分来自热释红外防盗传感器、有毒气体传感器和烟雾传感器的报警信号,当单片机检测到上述报警信号时,立即启动摘/挂机电路摘机,并从AT24C02存储器...  相似文献   

19.
First sex marks a significant transition for most adolescents, yet teens often report that it was unplanned. Seventy-four college students participated in exploratory focus groups about their first sex. Although initially asked whether their first sex was spontaneous or planned, many participants revealed evidence of forethought or anticipation, signifying a third option, anticipation. This study suggests that the development and timing of sexual health messages should build on the apparent, albeit often unacknowledged, planning and thought that accompany the transition to first sex. Specifically, during the time immediately preceding first sex, young people might be particularly open to such messages.  相似文献   

20.
通过专家访谈和录像解析综合考察和阐述了足球比赛中的沟通与信号传递.结果显示:中老年和青少年足球比赛中的沟通与信号传递有着各自特点;沟通和信号传递与知识、经验、心理以及与其他人熟悉程度等因素有关;各位置球员应当具备不同的沟通信号传递能力.  相似文献   

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