Effects of d-amphetamine, chlorpromazine, and chlordiazepoxide on intercurrent behavior during spaced-responding schedules.

Effects of d-amphetamine, chlorpromazine, and chlordiazepoxide on lever pressing under direct control of spaced-responding schedules were compared with effects on intercurrent drinking and wheel running in the rat. Drug effects on lever pressing were systematically related to dose and were consistent for all animals; drug effects on intercurrent behavior were generally different for each animal. In the case of lever presses, increasing doses of d-amphetamine first increased and then decreased response rate, increasing doses of chlorpromazine produced graded decreases in response rate, and doses of chlordiazepoxide up to 40 mg/kg produced no effect on response rate. These data are discussed in context with the concept of schedule control, and it is suggested that the behavioral pharmacology of intercurrent behavior be explored as a useful procedure in the experimental analysis of intercurrent behavior.     

Concurrent second-order schedules of reinforcement

Responses on one key (the main key) of a two-key chamber produced food according to a second-order variable-interval schedule with fixed-interval schedule components. A response on a second key (the changeover key) alternated colors on the main key and provided a second independent second-order variable-interval schedule with fixed-interval components. The fixed-interval component on one variable-interval schedule was held constant at 8 sec, while the fixed interval on the other variable-interval schedule was varied from 0 to 32 sec. Under some conditions, a brief stimulus terminated each fixed interval and generated fixed-interval patterns; in other conditions, the brief stimulus was omitted. Relative response rate and relative time deviated substantially from scheduled relative reinforcement rate and, to a lesser extent, from obtained relative reinforcement rate under both brief-stimulus and no-stimulus conditions. Matching was observed with equal components on both schedules; with unequal components, increasingly greater proportions of time and responses than the matching relation would predict were spent on the variable-interval schedule containing the shorter component. Preference for the shorter fixed interval was typically more extreme under brief-stimulus than under no-stimulus schedules. The results limit the extension of the matching relation typically observed under simple concurrent variable-interval schedules to concurrent second-order variable-interval schedules.     

Children's interpretation of adult nonreaction: A trial-by-trial self-report assessment and evidence for contrast effects in an observational context

The study investigated children's interpretation of blank reaction (nonreaction) from one adult to another as a function of its pairing with positive or negative overt feedback. Each child watched through a one-way mirror as an evaluating adult provided feedback to a second adult who was performing on a two-choice discrimination task. After six initial blank reaction trials, children observed one of four types of feedback combinations over 60 experimental trials: (a) right feedback on some trials and blank reactions on others, (b) wrong feedback on some trials and blank reactions on others, (c) right, wrong, and nonreaction on different trials, or (d) nonreaction on all trials. There was little evidence that children consistently interpreted blank reaction as meaning right independent of feedback combination. In contrast, in the Right-Blank and Wrong-Blank feedback combinations, children interpreted blank as meaning the opposite of the overt feedback it was paired with on over two-thirds of the trials, with no sex differences or test anxiety effects.     

Inducing ordinal and cardinal representations of the first five natural numbers

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.     

Selective imitation of the passive construction through modeling

Six 4- to 5-yr-old subjects were exposed to five sessions in which an adult model used passive sentences to describe a set of modeling stimuli. Probe stimuli, which the subjects were asked to describe without benefit of modeling and without selective reinforcement were interspersed among modeling stimuli. A matched group of control subjects received probletrials but no modeling trials. Both groups of subjects were subsequently tested on their ability to comprehend active and passive sentence forms. Every subject in the experimental group produced passive sentences on probe trials even though there was considerable variability in the number of passives produced. No control subject produced passives. The modeling procedure increased the comprehension scores of the experimental group above those of the control group though the scores of both groups were above chance. The results were contrasted with earlier studies in which modeling was ineffective in producing passive usage and in which comprehension of the passive was not demonstrated by even older children.     

PDP启动型实验程序与Richardson-Klavehn模型的比较研究

2个实验对PDP的启动型实验程序与Richardson-Klavehn的修正模型进行了比较研究,通过对指示语的操纵,考察提取策略是否完全受意志控制,以及注意水平、刺激材料、测验类型、加工水平对被试作业的影响.结果发现刺激材料对有意识控制记忆的实验结果影响很大,对PDP的无意识自动加工参数无影响;启动型实验程序的结果与PDP理论相当一致;提取策略不一定是受意志精确控制的.     

Oculomotor behavior and the level of repetition in motor practice: Effects on pupil dilation,eyeblinks and visual scanning

The benefits of less repetitive practice in motor learning have been explained by the increased demand for memory processes during the execution of motor skills. Recently, a new perspective associating increased demand for perception with less repetitive practice has also been proposed. Augmented information gathering and visual scanning characterize this higher perceptual demand. To extend our knowledge about mental effort and perceptual differences in practice organization, the association between oculomotor behavior and type of practice was investigated. We required participants to press four keys with different absolute and relative timing goals during the acquisition phase. An eye-tracker captured visual scanning of the skill’s absolute and relative information displayed on the screen. Participants were tested 24 h after acquisition by a retention and transfer test. A higher level of both pupil dilation and amount of eyeblinks indicated an increased mental effort in less repetitive practice compared to more repetitive practice. Visual scanning of the skill’s relative and absolute information was specific to the type of practice. The findings indicate many differences in oculomotor behavior associated with the practice schedule.