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61.
62.
Two hypotheses were tested about how young children answer questions with the quantifiers all and some: (a) that children use syntactic cues in determining which noun phrase is quantified, and (b) that children evaluate a some-statement as part of evaluating an all-statement. To test these hypotheses, the same group of 60 4- to 7-year-olds were asked four contrasting types of quantitative questions. The results indicated that children can use syntactic cues under some presentation conditions. However, there was no evidence for an asymmetry between the all-and some-questions. A model of how young children might answer quantitative questions was then considered.  相似文献   
63.
Clinical and autopsy studies were made on a right-handed man who had central deafness and subcortical motor aphasia, and the literature on central deafness and on subcortical motor aphasia was analyzed. Central deafness is due to bilateral destruction of the primary auditory cortex. It is sometimes difficult to distinguish from word deafness and from auditory agnosia, which are due to pathology in other parts of the temporal lobes. There is almost always some preserved hearing in central deafness, possibly from some auditory pathway other than the classical pathway. In this patient the subcortical motor aphasia was due to bilateral destruction of the motor cortex for the mouth and throat. In some other cases subcortical motor aphasia was due to the same pathology that usually causes Broca's aphasia; in these cases the unexpected preservation of writing was perhaps related to some difference in how language functions were organized in the brain.  相似文献   
64.
Typically in large residential facilities for retarded persons, meals are served in an institutional style that does not appear to encourage appropriate peer interactions. An ecological program alternative is serving meals in a family style. The present study was designed to examine both the feasibility of serving family style meals and the effects of family style meal service on mealtime language. Five retarded young adult male residents, who had some conversational skills and appropriate table manners, participated in this study. The experimental design involved a multiple baseline analysis across meals (dinner, lunch, and breakfast). Observers coded the youths' mealtime verbalizations according to the type, content, and direction of the verbalizations and they recorded the length of the meals. The analysis of the verbalization data indicated that during family style meals the participants spoke substantially more often than during institutional style meals. Increases in peer-directed conversation about the meals primarily accounted for the verbalization changes. Family style serving also resulted in the youths spending more time with their meals. In addition, social validation measures suggested that the family style procedures were preferred by the consumers (participants, staff, and concerned community members).  相似文献   
65.
Influences of extended training and temporal contingencies on reaction time were studied in relation to developmental differences. Older and younger men were trained on a chained schedule in which completion of a variable interval produced a terminal link in which reaction time was measured. The reaction-time procedure involved a conditional discrimination with matching to sample in one component and oddity matching in the other. During baseline training, no time limit was placed on the response to the discrimination choice stimuli. Subsequently, increasingly severe time limits were imposed over a series of sessions. Older and younger men showed increased speeds (decreased reaction times) when temporal contingencies were imposed, and these changes were maintained during post-training baseline sessions when there was unlimited time in which to respond. The younger men generally responded faster than the older ones, and age differences were not appreciably reduced during the course of the experiment. The results indicated the feasibility of studying reaction time in human subjects using operant procedures analogous to those developed for the study of nonverbal organisms.  相似文献   
66.
The capacity to selectively attend to only one of multiple, spatially separated, simultaneous sound sources—the “cocktail party” effect—was evaluated in normal subjects and in those with anterior temporal lobectomy using common environmental sounds. A significant deficit in this capacity was observed for those stimuli located on the side of space contralateral to the lobectomy, a finding consistent with the hypothesis that within each anterior temporal lobe is a mechanism that is normally capable of enhancing the perceptual salience of one acoustic stimulus on the opposite side of space, when other sound sources are present on that side. Damage to this mechanism also appears to be associated with a deficit of spatial localization for sounds contralateral to the lesion.  相似文献   
67.
In the UK, excessive fruit machine playing is the most documented form of pathological gambling amongst adolescents. Although there have been a few retrospective questionnaire studies in adolescent fruit machine gambling, there has been very little systematic observational fieldwork into the behaviour. The studies reported explore the social world of fruit machine playing using data collected via the monitoring of 33 UK amusement arcades employing participant and non-participant observation methodologies. The basic aims were to observe the arcade clientele and their behavioural characteristics, and to examine motivations for machine playing. Results suggest that level of adolescent gambling depends upon both time of day and time of year, and regular players conform to rules of etiquette and display stereotypical behaviours when playing fruit machines. The results also suggest that adolescents play fruit machines for a wide range of reasons including fun, to win money, to socialize, to escape and for excitement, and that inland and coastal arcades are frequented by different clienteles, probably as a function of the amusement machine available.  相似文献   
68.
Performance maintained under concurrent schedules consisting of a variable-interval avoidance component and a variable-interval positive-reinforcement component was studied in three human subjects using points exchangeable for money as the reinforcer. The rate of responding in the avoidance component increased, and the rate of responding in the positive-reinforcement component declined, as a function of the frequency of point-losses avoided in the avoidance component. The performance of all three subjects conformed to equations proposed by Herrnstein to describe behavior in concurrent schedules. The logarithms of the ratios of the response rates in the two components, and the logarithms of the ratios of the times spent in the two components, were linearly related to the logarithms of the ratios of the frequency of loss avoidance in the avoidance component to the frequency of reinforcement in the positive-reinforcement component. When a changeover delay of 5.0 sec was imposed, the slopes of the linear functions were close to 1.0 in the case of two subjects, whereas the third subject exhibited significant undermatching. For two subjects the changeover delay was then reduced to 2.0 sec; in both cases the slopes of the linear functions were lower than under the 5.0-sec condition. One subject participated in a third phase, in which no changeover delay was imposed; there was a further reduction in the slopes of the linear functions.  相似文献   
69.
Eighteen young adults performed a lever-pulling task for money. Subjects were initially exposed to a fixed-interval 80-second schedule and subsequently to one of three conjunctive schedules in which the added fixed-ratio requirement was set at either 10, 80, or 120 responses. Three fixed-interval response patterns emerged: high constant rate, intermediate rate, or low rate, with most subjects displaying the last. Conjunctive performance was related to the subjects' prior fixed-interval patterns and the conjunctive ratio requirements. Low-rate subjects tended to optimize reinforcement (maximum reinforcers for minimum responses) on conjunctive schedules. Response rate was directly related to ratio requirements. Subjects' performance closely corresponded to their verbal statements of the contingencies.  相似文献   
70.
Approximately 50% of all institutionalized, mentally retarded adults receive psychotropic medication to control inappropriate behavior. In this study, behaviors exhibited by five retarded adults were formally observed while they were on and off medication. Each subject had been receiving chlorpromazine for six or more years prior to the start of the study. The drug was withdrawn and readministered using a double-blind B-A-B (drug-placebo-drug) design. Effects were highly individualized. Some desirable behavior emerged when chlorpromazine was discontinued.  相似文献   
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