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1.
We report an investigation of the development of visual expectancies in 3.5-month-old infants. One of the infant's eyes was videorecorded as the infant watched a series of slides that were presented noncontingent on behavior. Babies were presented an alternating and an irregular series of 30 slides with a 700-msec onset duration separated by an interstimulus interval (ISI). The ISI for the alternating series was 1,100 msec, whereas the slides for the irregular series were separated by 900, 1,100, or 1,300 msec, randomly ordered. One-half of the babies saw the irregular series first, and one-half saw the regular series first. Babies in both groups provided evidence that they developed expectations for the visual events in the alternating series. Their reaction times (RTs) declined significantly from 3-5 "baseline" presentations, and their RTs were reliably faster during the alternating than the irregular series. Additionally, babies in the alternating-late group had significantly more stimulus anticipations during the alternating than during the irregular series. These findings indicate that 3.5-month-olds can detect regularity in a spatiotemporal series, will develop expectancies for events in the series, and will act on the basis of those expectancies even when those actions have no effect on the stimulus events. We believe that infants are motivated to develop expectations for noncontrollable spatiotemporal events, because these expectations permit them to bring their visual behavior under partial internal control.  相似文献   

2.
Many characteristics of a series of discrete independent hedonic events may be remembered by rats in terms of, for example, how many events were rewarded and how many were nonre-warded. Such memory for multiple hedonic events, which has been shown to be a potent factor controlling instrumental responding, was examined here in five investigations employing serial anticipation learning in a runway. It was found that the ability of rats to remember the hedonic events reward and nonreward is highly developed, accurate, and quite resistant to forgetting and interference. Rats not only remembered a rewarded event and a nonrewarded event, but they also remembered the order in which the two events occurred. Rats remembered how many nonrewarded events there had been accurately enough to suggest that they were using some form of a counting mechanism. Rats exhibited little forgetting of eight prior discrete hedonic events, one rewarded followed by seven nonrewarded, even when these occurred over an interval of 20 min and involved considerable potential interference. In the serial learning situation employed here, marked primacy effects were obtained, earlier nonrewarded trials in a series being better anticipated than later ones. The primacy effect was found to depend upon the type of series employed. By assuming that stimulus generalizations occur between the multiple hedonic events remembered by rats, all anticipatory learning obtained here could be explained in considerable detail.  相似文献   

3.
The lecture process was studied systematically with the following objectives: to reexamine the effects of time upon note-taking and immediate retention, to compare the relative effectiveness of spoken and written cues, and to investigate cuing schedules. Students were asked to view one of a series of videotaped lectures in which certain statements were highlighted by either spoken or written cues. The contents of students' notes and assessments of immediate recall and recognition provided the dependent measures. Students recorded increasingly less information in their notes over the course of the lecture, but retention of material from different portions of the lecture was essentially the same. Written-cued statements were recorded more frequently and retained better than statements preceded by spoken cues. Finally, the different schedules of cuing were shown to have subtle effects upon note-taking and recall.  相似文献   

4.
Rats received pairings of two stimuli with reward noncontingently in the Skinner box. During noncontingent pairings, the bar was immobilized. For Group CC 100% of the presentations of both stimuli were rewarded (S1 ±, S2 ±), for Group PP 50% of the presentations of each stimulus were rewarded (S1, ±, S2±), and for Group PC one stimulus was followed by reward on 50% of its presentations, while the second stimulus was followed by reward on 100% of its presentations (S1 ±, S2 ±). A fourth group received the stimuli and reward nonpaired. In a subsequent rewarded test phase, the response facilitating effects of the stimuli were evaluated. In the test phase all groups that received reward paired with S1, and S2 performed better in the presence of S1 and S2 than the group for which the stimuli were not paired with reward. For groups that received the stimuli paired with reward, a difference due to schedule of reward occurred when schedule of reward was varied within Ss (Group PC), but not when varied between Ss (Group PP vs Group CC). The specific form of this finding was that Group PC’s performance in the presence of S2 ± was more vigorous than its performance in the presence of S1 ± and was more vigorous than the performance of Groups PP and CC to S2. Group PC’s performance to S1 ± did not differ from that of Groups PP and CC to S1.  相似文献   

5.
In previous studies, we have shown that adding a supplementary cue in a prior-cuing treatment may dramatically reduce its initial effectiveness. This series of experiments was aimed at testing the hypothesis that such a lack of additivity among retrieval cues could be due to the combined reactivation of memory attributes related to incompatible behavioral responses. For that purpose, rats were partially trained to reach the lighted arm (light condition; usual training condition) or the darkened arm (dark condition) of a Y-maze in order to avoid an electric foot-shock. The first experiment demonstrates that animals learned the two versions of the task similarly and that an exposure to the light similarly acts as an effective retrieval cue after a 24-h interval. In the second experiment, the effectiveness of exposure to the grid alone and to the light alone as well as to the combined light + grid cue was investigated after a 21-day training-to-test interval in the light condition, where light was related to safety and grid was associated with the shock, and in the dark condition, where both light and grid were related to the shock. The results indicate that whereas the compound light + grid cue was an ineffective retrieval cue in the light condition, it acted as an effective retrieval cue in the dark condition, supporting the hypothesis that coherence between retrieval cues is a necessary condition for effective cuing.  相似文献   

6.
To demonstrate a facilitating stimulus effect, as opposed to an incentive effect, of food reward, rats were trained on an easy, light-dark discrimination with different amounts of reward for correct and incorrect responses (1-0, 2-0, 3-1, and 5-1 pellets, respectively), and with shock or no shock administered in the correct goalbox. Both errors and trials to criterion were fewer with a large reward differential (LRD: 2-0 and 5-1), as compared with a small reward differential (SRD: 1-0 and 3-1), but were not affected by the “base” reinforcement condition of either 1 or 0 pellets for the incorrect response. In addition, choice and arm speeds during early training were positively related to the combined, or average, number of pellets contingent upon both correct and incorrect responses, indicating a generalization of reward expectancies. Although shock uniformly suppressed arm speeds under all reward conditions, it facilitated discrimination learning in the SRD conditions. That such facilitation occurred only when the conditions of reward for correct and incorrect responses were relatively similar indicates that not only shock, but also food can function as a distinctive cue: As a stimulus selectively applied to one response, it can decrease the similarity of the alternatives, and, in this manner, it can faciltate performance.  相似文献   

7.
Instructional Science - The present study examines the effectiveness of incorporating worked examples with prompts for self-explanation into a middle school math textbook. Algebra 1 students...  相似文献   

8.
In Experiment 1, three groups of rats were trained on one of three serial patterns consisting of different numbers of .045-g food pellets, either the simple strong monotonie pattern 14-7-3-1-0 (Group SM) or one of two complex weak monotonie patterns, 14-5-5-1-0 (Group 5-5) or 14-9-1-1-0 (Group 1-1). Learning to anticipate the terminal 0-pellet element occurred faster in Group 1-1 than in Group SM, which in turn learned faster than Group 5-5. In Experiment 2, Groups SM, 5-5, and 1-1 were trained on the first four elements of the patterns experienced by their Experiment 1 counterparts and then were tested for their ability to extrapolate the series to include the addition of a 0-pellet element in the fifth position. Extrapolation behavior was better in Group 1-1 than in Group SM, which in turn performed better than Group 5-5. The results were shown to be consistent with a memory-discrimination model of serial learning and inconsistent with a rule-learning model based on pattern complexity.  相似文献   

9.
It is now well known in animal studies that spontaneous forgetting, as well as performance decrements resulting from other sources, can be alleviated by means of pretest treatments. Several previous experiments have shown that reliable forgetting is observed after a 25-day training-to-test interval on a relatively complex maze. This forgetting can be alleviated by pretest exposure to background stimuli in the experimental room. The effects of this treatment can be modulated by varying either the duration of the treatment or the length of the cuing-test interval. The purpose of the experiment presented here was twofold: (1) to demonstrate the multidimensionality of memories in our paradigm by comparing the effects of different reminder treatments, namely pretest access to the reinforcer and contextual cuing, and (2) to test the general hypothesis, formulated by Spear (1978, p. 418), that “the elicitation and retrieval of the target attribute of a memory depend on the arousal of a sufficientnumber or kind of the remaining attributes of this memory.” The data showed that pretest food reinforcement had no significant effect on retention performance; that pretest contextual cuing did, in some precise conditions, alleviate forgetting; and that some combinations of context and reinforcement had what amounted to a synergistic action on retention performance.  相似文献   

10.
王海棻先生的《记时词典》是中国第一部关于记时词语的专门词典,其所搜集的记时词语及其书证都很丰富,受到古代汉语和古代文史学界的重视和好评。但是在词条立项与释义、书证选择与引用上,尚存在一些不足。《庄子》是先秦时期重要的哲学著作和经典文献,在对当时词汇的运用和后世词汇的发展方面贡献和影响很大。《庄子》的记时词语对《记时词典》增补词条、改正释义、增加或提前书证等都有很好的补正作用。  相似文献   

11.
Honeybees foraging for sucrose at a laboratory window were trained in a series of ten 100-trial problems to choose between two targets differing in odor, one of them providing 10 µl of a 50% sucrose solution and the other 10 µl of water. In 9 of the problems, two odors were used, and the reward ratio was varied systematically over a wide range. In the 10th problem, three odors were used in an ambiguous-cue (A+/B?, B+/C?) design. The results were predicted quantitatively, and with substantial accuracy, from a simple theory of learning and choice developed in previous work on simultaneous discrimination in honeybees.  相似文献   

12.
Past experiments have reported that rats encountering reward (R) or nonreward (N) goal events emit odors that can be utilized as discriminative stimuli for instrumental behavior by conspecifics. In the present study, thirsty male rats were aversively conditioned by ingestional toxicosis to R and N odors, and their suppression of water consumption in the presence of these odors was measured. Thirsty trained donors were placed into chambers containing R or N goal events to generate, respectively, the R or N odors. Test animals were given eight differential conditioning trials (four with one odor as CS+; four with the other as CS?), involving placement into an odorcontaining chamber with water available, followed by a LiCl injection on CS+ trials. Animals tested in their CS+ odor consumed significantly less water than did CS? and control subjects. Both R and N odors were conditioned by aversive means and readily discriminable from each other. This represents the first laboratory demonstration of aversive conditioning of such naturally produced odors, and it suggests that aversive conditioning may be useful in the study of odorous emissions generally. Implications for innate meanings of R and N odors are discussed.  相似文献   

13.
The greater the dissimilarity between exteroceptive stimuli, the easier it is to discriminate between them. To determine whether a similar relationship holds for memories produced by reward events, rats in three runway investigations received trials in pairs, the number of food pellets (0.045 g) occurring on Trial 1 indicating whether reward or nonreward would occur on Trial 2. In each investigation, discriminative responding on Trial 2 was better the larger the difference in reward magnitude on Trial 1. This finding was obtained under a wide variety of conditions: for example, when the larger of two reward magnitudes on Trial 1 signaled nonreward on Trial 2 (Experiment 1, 10 vs. 2 pellets); when the smaller of two reward magnitudes on Trial 1 signaled nonreward on Trial 2 (Experiment 2, 10 vs. 2 pellets); and when the same magnitude of reward on Trial 1 signaled nonreward on Trial 2 (Experiment 3, either 5 pellets or 0 pellets). The findings obtained here indicate that the greater the dissimilarity between reward magnitudes, the greater the dissimilarity between the memories they produced and, thus, the easier it is to discriminate between them. It is suggested that the present results may provide a basis for understanding findings obtained in other instrumental learning investigations in which reward magnitude is varied.  相似文献   

14.
In a series of four experiments with free-flying honeybees, individual foragers were trained with targets of two different colors that contained 5 or 20 μl of 50% sucrose solution. The two targets were singly presented in quasi-random sequences on each visit, with the amount of reward to be found on each target perfectly predictable from its color. The number of training visits (4–32) was varied both within and between experiments, and so also was the relative frequency of trials with the 5- and 20-μl targets (1:1, 2:1, 3:1, and 9:1). At the conclusion of training under each condition, unrewarded responses to the targets were measured in a 10-min extinction test, with the targets presented either separately to two different groups of animals (Experiment 1) or as a pair (Experiments 2–4). When the number of training trials with each target was the same (Experiments 1 and 2), the animals responded more in extinction to the 20-μl target than to the 5-μl target, although there was a decline in the overall level of responding to both targets (an overlearning-extinction effect) as the number of training trials increased. After nine times as many, or only three times as many, training trials with the5- μl target as with the 20-μl target, the animals responded more in extinction to the 5-μl target (Experiment 3); after twice as many training trials with the 5-μl target as with the 20-μl target, there was equal responding to both (Experiment 4). The preferences shown in the choice tests of Experiments 2–4 could be simulated rather accurately on the assumptions of a model previously developed to deal with the discrete-trials choice behavior of honeybees and the further assumption that associative strength grows at a rate increasing with amount of reward to an asymptote independent of amount of reward.  相似文献   

15.
For a group of goldfish trained in a runway under conditions of highly massed practice, reduction in magnitude of reward produced a gradual decline in performance to the level of a small-reward control group but no suggestion of negative successive contrast. These results are consistent with the suggestion that reward plays a somewhat different role in the learning of fish and rats. They also serve to extend the range of conditions under which the stimulus aftereffects of reward come to control the instrumental behavior of fish.  相似文献   

16.
Two experiments assessed the role of aftereffect learning in rats rewarded with sucrose solutions. In Experiment 1, rats were trained in a single straight runway for two trials on each of 18 days, each trial terminating with either large (20% scurose) or small (3% sucrose) reward. The ITI was 3–5 min. The sequence of daily rewards for each of four groups was small-small (SS), small-large, (SL), large-small (LS), or large-large (LL). Response patterning and a simultaneous negative contrast effect were observed in LS and SL relative to the consistently rewarded controls. During 10 massed extinction trials, resistance to extinction was greatest for Group SL, followed in order by Groups SS, LL, and LS. Experiment 2 examined single alternation of large and small rewards administered for 10 trials on each of 31 days with an ITI of 60 sec. Reward for one group was 20% or 3% sucrose while another received 1 or 10 45-mg Noyes pellets. Appropriate patterning developed only in the food-pellet rewarded animals. The overall results suggest that sucrose rewards may produce high-amplitude and long-duration aftereffects which interfere with learning in designs employing several massed daily trials, but which may facilitate learning—relative to food-pellet rewards—with longer intertrial intervals and fewer daily trials.  相似文献   

17.
The literature relevant to incentive contrast effects is reviewed, with emphasis on the data published since the reviews by Black (1968) and Dunham (1968). Contrary to the evidence available for the earlier reviews, the current literature indicates that positive contrast is a reliable phenomenon. Its occurrence is facilitated by use of a constant delay of reward, use of a long runway, or possibly by a shift while a negative contrast effect, resulting from a previous shift, is still present in the animals’ behavior. Positive contrast also occurs in consummatory behavior when sucrose or saccharin solutions are shifted. Conditions that are ineffective in producing positive contrast are reviewed, as are the effects of numerous variables on both successive and simultaneous contrast. In addition, positive and negative contrast effects resulting from shifts in delay or percentage of reward, contrast resulting from shifts in sucrose, saccharin, or ethanol solutions, contrast in choice behavior, and transsituational contrast are reviewed. The relationship of the data to several theoretical interpretations of contrast is also considered.  相似文献   

18.
A study was conducted to determine the effects of external reward in the form of prizes on the performance of college students in a paired-associate learning task in which subjects were asked to recall a real word associated with a nonsense word. Two groups, one of whom was offered a prize, received the S-R pairs with no aid (no mediators); and two groups, one of whom was offered a prize, received the S-R pairs with a sentence-pictorial aid mediator. Results of two-way ANOVA supported the hypothesis that the No Prize/Aided and No Prize/NonAided groups would exhibit performance of higher quality than the groups offered prizes. The dependent measure was number of correct responses over six trials.  相似文献   

19.
Pigeons were trained on delayed matching-to-sample trials in which red and green sample stimuli were equally often followed by color comparisons and by line-orientation comparisons. The color samples were preceded and accompanied by cues (a triangle or a black dot) that signaled whether the comparisons on that trial would be colors or lines. Length of the retention interval was manipulated during testing, and probe trials were included on which the dimension of the comparison stimuli either was cued incorrectly or was not cued. Accuracy on incorrectly cued and on no-cue trials was less than that on correctly cued trials, and the magnitude of this effect was not influenced by the length of the retention interval. Accuracy on incorrectly cued and on no-cue trials was equivalent, and was greater than chance. The data are inconsistent with two dual-coding interpretations of the effects of incorrectly cuing the dimension of the comparison stimuli in which it is held that both retrospective and prospective sample coding occurs in this task.  相似文献   

20.
A three-compartment box was used, and a reward odor, or nonreward (extinction) odor, produced by another rat, was present in the middle compartment. Two control odor procedures were also used. The results showed that rats will approach a location in which another rat has previously been given reward more rapidly than they will escape from that location, but showed the opposite effect when the odor was produced by a rat undergoing extinction. The mere presence of an odor associated with another rat had the effect of producing much slower locomotion as compared to a no-odor control condition.  相似文献   

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