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971.
The prediction that the ordinal property of natural number symbols (using these symbols to represent the terms in an ordered progression) is more easily learned than the cardinal property of natural number symbols (using these symbols to represent the manyness of collections) was examined in this experiment. Preschoolers who evidenced no proficiency with either the ordinal or cardinal properties of natural number symbols were trained to acquire these properties via simple feedback. Both properties proved to be trainable. The most important findings were that the ordinal property was much easier to train than the cardinal property, ordinal training effects were more durable across a 1-week interval than cardinal training effects, and ordinal training appeared to transfer better than cardinal training.  相似文献   
972.
With the component selection measure developed by Hale and Morgan (1973), children's use of selective attention was assessed at six levels of learning, ranging from undertraining to overtraining, and this function was examined at each of ages 4, 8, and 12. It was found that, as the children learned the task, they maintained a relatively wide focus of attention, acquiring information about both features of the stimuli, color and shape. Thus, contrary to the model under investigation, the children did not exercise a high degree of selectivity as they approached mastery of the task; nor did overtraining produce the expected “broadening” of attention, as the children acquired little stimulus information beyond the point at which criterion had been reached. The data were interpreted to be more consistent with a model that assumes the bulk of stimulus learning to occur prior to task mastery.  相似文献   
973.
Children at four age levels (4, 6, 8, and 10 years) were given continuous recognition tasks using concrete noun, abstract noun, and pictorial stimuli in a 4 × 3 factorial design. Pictures were recognized significantly better than concrete and abstract nouns at the 4- and 6-year age levels and significantly better than abstract nouns at the 8- and 10-year age levels. This supported Paivio's contention that pictures are easier to remember than words because of a greater possibility of dual encoding, while Rohwer's contention that there is a shift in recognition memory development received no support. There were no significant differences between recognition of concrete and abstract nouns at any age level, which opposed the findings from adult studies and suggested that Paivio's theoretical orientation would have to be extended in order to account for developmental data. Recognition for both concrete and abstract nouns was found to be linear and increasing significantly with age, but no age trends for picture recognition were found.  相似文献   
974.
Instrumental licking of .4% saccharin solution was increased by the contingent opportunity to lick a less-preferred saccharin solution when the contingency schedule deprived the subject of the contingent response, but not otherwise. Schedules that imposed comparable amounts of response deprivation produced comparable increases in instrumental responding. The results support the hypothesis that instrumental responding will increase if and only if the contingency schedule deprives the subject of the contingent response. They also support the implication that the predicted increase will occur even if the contingent response has a lower operant level than the instrumental response.  相似文献   
975.
A comparison between the reinforcement strength of self-administered and externally imposed brain stimulation was undertaken. Rats performed on a chain schedule in order to receive brain stimulation, either selfadministered or imposed, during the second component of the chain. Response rates during the first component of the chain schedule indicated that self-stimulation was more reinforcing than imposed stimulation. In addition, contrast, both positive and negative, seemed to be present. It was concluded that reinforcement strength may be enhanced when the subject controls the presentation of reinforcement.  相似文献   
976.
General activity subsequent to reward (R) and nonreward (N) was monitored at 5-sec intervals with a stabilimeter in the runway goal box. Activity of never-rewarded control Ss was also measured. In Expt 1 it was found that the frustration effect (difference between N- and R-trial activities) disappeared after about 40 sec of goal box confinement. This disappearance of the frustration effect was due to activity increase on R trials rather than activity decrease on N trials as a function of time. Comparison of N-trial activity with control group activity indicated that frustration does not dissipate within 60 sec. Expt 2 investigated activity following reward and nonreward as a function of reward magnitude. Evidence from these experiments suggests that the late R-trial activity increase results from frustration, possibly conditioned to apparatus cues on N trials.  相似文献   
977.
Continuous availability of a sand blocked tube elicited intense and persistent digging by laboratory rats. Neither training nor prior exposure to the apparatus were necessary for response initiation. Continuous presence of an open pile of sand would not elicit digging. No theoretical explanation is offered.  相似文献   
978.
The effects of the relationship between the presentation of a verbal stimulus (“right”) and an established reinforcer (M&Ms) on the reinforcement efficacy of the verbal stimulus was tested with three groups of retarded boys. Blocks of training and test trials alternated. During training of the Discriminative Group, “right” reliably preceded candy. For the Contiguous Group, “right” accompanied candy, and for the Random Group “right” and candy were programmed independently. “Right” promoted learning in the Discriminative Group but did not in the latter two groups. The results support Cairns' analysis of the often found failure of approval to be an effective reinforcer in laboratory tasks.  相似文献   
979.
Studies of choice holding food‐amount ratio constant while varying food‐rate ratio within sessions showed that local changes in preference depend on relative amount of food. The present study investigated whether sensitivity of choice to food‐rate ratio and sensitivity to food‐amount ratio are independent of one another when food‐rate ratios are varied across sessions and food‐amount ratios are varied within sessions. Food deliveries for rats’ presses on the left and right levers were scheduled according to three different food‐rate ratios of 1:1, 9:1, and 1:9; each food‐rate ratio lasted for 106 sessions and was arranged independently of seven food‐amount ratios (7:1, 6:2, 5:3, 4:4, 3:5, 2:6, and 1:7 food pellets) occurring within sessions in random sequence. Each amount ratio lasted for 10 food deliveries and was separated from another by a 60‐s blackout. Sensitivity to rate ratio was high (1.0) across food deliveries. Sensitivity to amount ratio was low when food rates were equal across alternatives, but was high when rate ratio and amount ratio opposed one another. When rate ratio and amount ratio went in the same direction, choice ratio reached an elevenfold limit which reduced sensitivity to approximately zero. We conclude that three factors affect sensitivity to amount: (1) the limit to preference, (2) the equal effect on preference of amounts greater than four pellets, and (3) the absence of differential effects of switches in amount in the equal‐rates (1:1) condition. Taken together, these findings indicate that rate and amount only sometimes combine independently as additive variables to determine preference when amount ratios vary frequently within sessions.  相似文献   
980.
Prior research shows that learners have idiosyncratic responses to error‐correction procedures during instruction. Thus, assessments that identify error‐correction strategies to include in instruction can aid practitioners in selecting individualized, efficacious, and efficient interventions. The current investigation conducted an assessment to compare 5 error‐correction procedures that have been evaluated in the extant literature and are common in instructional practice for children with autism spectrum disorder (ASD). Results showed that the assessment identified efficacious and efficient error‐correction procedures for all participants, and 1 procedure was efficient for 4 of the 5 participants. To examine the social validity of error‐correction procedures, participants selected among efficacious and efficient interventions in a concurrent‐chains assessment. We discuss the results in relation to prior research on error‐correction procedures and current instructional practices for learners with ASD.  相似文献   
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