11—14个月儿童的语言获得——成人的言语教授和儿童的模仿学习

对儿童言语记录个案的分析表明:儿童在11—14个月期间开始获得词。此时儿童所获得的词,主要是与儿童日常生活或动作相联系的名词和动词,其次是象声词。这些词语87.5％来源于成人的言语教授和儿童相应的模仿学习。 成人的言语教授和儿童相应的模仿学习总是由成人结合情景进行的,具有很高的选择性。儿童对成人言语的学习并不是简单地模仿,而是有一定的主动性和创造性,这在一定程度上规定着成人言语教授的作用。由此可见,儿童言语的获得是在人类特有的大脑以及言语器官发育的基础上,在与人们交际过程中,经过成人的言语教授,并经儿童有选择的模仿学习和概括而成的。     

Effects of self-correction on the spelling performance of junior high students with learning disabilities

The purpose of this study was to compare the effects of Self-Correction and Traditional spelling on the acquisition, maintenance, and generalization of spelling words with five junior high school students with learning disabilities. During Traditional spelling students received a weekly list of 20 unknown words. Daily 20-minute assignments with these words varied among writing them, arranging them in alphabetical order, dividing the words into syllables, and using a dictionary to locate word meaning. Students were tested on the 20 words at the end of the week. During Self-Correction, students received 20 words on a 5-column sheet of paper. Columns were arranged so that stimulus words could be hidden by folding the paper back, and later exposed after the teacher dictated and the student wrote the words. Students used proofreading marks to self-correct. Sessions lasted 20 minutes, and weekly, delayed, and generalized assessments were conducted. Results indicated that for all five students the Self-Correction procedure was more effective for word acquisition than Traditional spelling. Also, for four of the five students, maintenance of words was higher under Self-Correction. Generalization occurred for three students. Finally, measures of social validity indicated that the students preferred Self-Correction over Traditional spelling, although two teachers in regular classrooms did not notice significant changes in the overall spelling performance for the students. Implications for the classroom practitioner are discussed.     

Effects of D-amphetamine on response acquisition with immediate and delayed reinforcement.

The present study examined in 8-hour sessions the effects of d-amphetamine (1.0, 5.6, and 10 mg/kg) on the acquisition of lever-press responding in rats that were exposed to procedures in which water delivery was delayed by 0, 8, or 16 seconds relative to the response that produced it. Both nonresetting- and resetting-delay conditions were studied. Although neither shaping nor autoshaping occurred, substantial levels of operative-lever responding developed under all conditions in which responses produced water. The lowest dose (1.0 mg/kg) of d-amphetamine either had no effect on or increased operative-lever pressing, whereas higher doses typically produced an initial reduction in lever pressing. Nonetheless, overall rates of operative-lever pressing at these doses were as high as, or higher than, those observed with vehicle. Thus, response acquisition was observed under all reinforcement procedures at all drug doses. In the absence of the drug, most responding occurred on the operative lever when reinforcement was immediate. Such differential responding also developed under both nonresetting- and resetting-delay procedures when the delay was 8 seconds, but not when it was 16 seconds. d-Amphetamine did not affect the development of differential responding under any procedure. Thus, consistent with d-amphetamine's effects under repeated acquisition procedures, the drug had no detrimental effect on learning until doses that produced general behavioral disruption were administered.     

知识向技能转化的影响因素

将知识向技能的转化过程分为 :陈述性编码阶段、程序性编码阶段 ,并假设存在一些因素影响陈述性编码向程序性编码的转化过程 ,控制好这些关键因素将有利于提高教学质量。为证明此假设 ,设计了四个实验。实验一、二结果表明 ,发现学习和接受学习中原有知识水平、概念地图策略等因素显著影响陈述性编码阶段 ;实验三、四结果表明 ,发现学习和接受学习中变式练习、解题策略指导等因素显著影响程序性编码阶段 ,对以上实验数据的再分析得出这两阶段存在明显的相互制约关系 ,根据以上结论和 E.D.Gagne的信息加工模型 ,构建了一个智慧技能获得的信息加工模型。     

ACQUISITION AND CROSS-SETTING GENERALIZATION OF MANUAL SIGNS WITH SEVERELY RETARDED INDIVIDUALS

In this study, we assessed the effect of a transfer of stimulus control procedure on the acquisition and cross-setting generalization of manual signs with four profoundly retarded individuals. Two individuals were trained to produce appropriate signs to verbal instructions, whereas the other two were trained until manual signs were controlled by visual stimuli (objects). Data obtained from three probe situations (two for one individual) constituted the dependent variables of the investigation. The results, gathered within a multiple-baseline design across signs showed that (a) individuals acquired the trained signs and (b) maintenance and generalization across settings (classroom, ward) and persons (teachers, ward staff) occurred, but was highly variable between and within individuals.     

Rapid acquisition of discrete-trial lever-press avoidance: effects of signal-shock interval

Acquisition of discrete-trial lever-press avoidance learning was studied in three experiments. Experiment I compared a new training procedure, which produces rates of lever-press avoidance learning comparable to those obtained in shuttle boxes, with a “conventional”, less efficient training procedure. A factorial design was used to compare continuous versus intermittent shock and a long-variable versus a short-fixed signal-shock interval. Learning was best in the groups trained with the long and variable interval and poorest in those trained with the short and fixed interval. Type of shock had no effect. Experiment II separated the effects of duration from those of variability of the signal-shock interval. Fixed and variable intervals of 10 and 60 sec were tested and duration was the only significant factor. Experiment III addressed the effect of the differential opportunity to avoid provided by long signal-shock intervals by varying this interval from 10 to 60 sec in 10-sec steps. Only the 10-sec group showed slow acquisition relative to the others. Analysis of avoidance response latencies showed that the distributions for all groups were positively skewed and that skewness increased with increasing duration of the signal-shock interval. At intervals longer than 20 sec, the animals made progressively less use of their increased opportunity to respond. The data do not support the opportunity-to-respond interpretation of the effects of duration of signal-shock interval and suggest that some type of inhibitory process may block lever-press avoidance learning at intervals as short as 10 sec. The significance of these findings for species-specific defense reaction and preparedness theories was emphasized.     

Effects of scopolamine on repeated acquisition of radial-arm maze performance by rats.

Rats repeatedly acquired the performance of selecting only the four baited arms in an automated eight-arm radial maze, with the arms containing food pellets randomly assigned prior to each session. During each 14-trial (trial: obtain all four pellets) daily session, the number of errors (selecting nonbaited arms or repeating arm selections) showed a within-session decline, and choice accuracy for the first four arm selections showed a positive acceleration across trials for all rats. An index-of-curvature statistic, calculated for total errors, was used to quantify both the within- and between-session improvement of performance. Scopolamine (0.03 to 0.3 mg/kg, ip), but not methylscopolamine (0.3 mg/kg), reduced the accuracy of the first four selections of each trial and increased total within-session errors for all rats. Session times also were increased by scopolamine. An examination of within-session accuracy showed only slight signs of improvement at the higher dosages of scopolamine. The results indicate that behavior in transition states maintained by reinforcement contingencies in the radial maze is similar to that maintained by extended chained schedules, despite the fact that some of the stimuli controlling behavior in the maze are absent at the moment behavior is emitted.     

Acquisition and maintenance of autoshaped key pecking as a function of food stimulus and key stimulus similarity.

The results of a number of recent studies suggest that acquisitions of autoshaped key pecking in pigeons is affected by the similarity of the grain-hopper stimulus and response-key stimulus. In Experiment 1 this hypothesis was tested by training independent groups of pigeons to key peck under six different hopper-stimulus and key-stimulus similarity conditions, and three procedures containing either immediate reinforcement, variable delay of reinforcement, or omission of reinforcement for key pecking. Number of trials to acquisition was found to be related to the similarity variable. Maintained responding was affected by the response-reinforcer contingency. This effect was found both within and between subjects. Under two of the contingencies (automaintenance and omission), maintained responding continued to be affected by the similarity of the hopper stimulus and key stimulus. In Experiment 2 pigeons were given omission training with a hopper light on or off. Both acquisition and maintenance of key pecking were facilitated by the presence of the hopper light. The present findings suggest that much of the responding reported in various automatic shaping and training procedures may reflect the effects of key stimulus/food stimulus similarity.     

PROGRAMMING “LOOSE TRAINING” AS A STRATEGY TO FACILITATE LANGUAGE GENERALIZATION

This study investigated the generalization of spontaneous complex language behavior across a nontraining setting and the durability of generalization as a result of programming and “loose training” strategy. A within-subject, across-behaviors multiple-baseline design was used to examine the performance of two moderately retarded students in the use of is/are across three syntactic structures (i.e., “wh” questions, “yes/no” reversal questions, and statements). The language training procedure used in this study represented a functional example of programming “loose training.” The procedure involved conducting concurrent language training within the context of an academic training task, and establishing a functional reduction in stimulus control by permitting the student to initiate a language response based on a wide array of naturally occurring stimulus events. Concurrent probes were conducted in the free play setting to assess the immediate generalization and the durability of the language behaviors. The results demonstrated that “loose training” was effective in establishing a specific set of language responses with the participants of this investigation. Further, both students demonstrated spontaneous use of the language behavior in the free play generalization setting and a trend was clearly evident for generalization to continue across time. Thus, the methods used appear to be successful for training the use of is/are in three syntactic structures.     

Effects of d-amphetamine, cocaine, and phencyclidine on the acquisition of response sequences with and without stimulus fading.

In each of three components of a multiple schedule, monkeys were required to emit a different sequence of four responses in a predetermined order on four levers. Sequence completions produced food on a fixed-ratio schedule. Errors produced a brief timeout. One component of the multiple schedule was a repeated-acquisition task where the four-response sequence changed each session (learning). The second component of the multiple schedule was also a repeated-acquisition task, but acquisition was supported through the use of a stimulus-fading procedure (faded learning). In a third component of the multiple schedule, the sequence of responses remained the same from session to session (performance). At higher doses, d-amphetamine, cocaine, and phencyclidine decreased the overall rate of responding and increased the percent errors in all three components. At lower doses, however, the three drugs produced selective effects on errors. Errors were increased in the learning component at lower doses than those required to disrupt the behavior in the faded-learning component. The performance component tended to be the least sensitive to disruptive drug effects. The data are consistent with the view that stimulus fading can modulate the effects of drugs on acquisition.