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71.
Concurrent variable-ratio schedules of electrical brain stimulation, food, and water were paired in various combinations as reinforcement of rats' lever presses. Relative prices of the concurrent reinforcers were varied by changing the ratio of the response requirements on the two levers. Economic substitutability, measured by the sensitivity of response ratio to changes in relative price, was highest with brain stimulation reinforcement of presses on both levers and lowest with food reinforcement of presses on one lever and water reinforcement of presses on the other. Substitutability with brain stimulation reinforcement of presses on one lever and either food or water reinforcement for presses on the other was about as high as with brain stimulation for presses on both levers. Electrical brain stimulation for rats may thus serve as an economic substitute for two reinforcers, neither of which is substitutable for the other.  相似文献   
72.
By using a self-management program, a 25-yr.-old white male was able to decrease the amount of junk food and beverage consumed while increasing the amount of healthier food and beverage ingested during evening snacks. This change was evident at 6 wk. and at a 6-mo. follow-up. Factors contributing to this success were discussed.  相似文献   
73.
Results of auditory speech experiments show that reaction times (RTs) for place classification in a test condition in which stimuli vary along the dimensions of both place and voicing are longer than RTs in a control condition in which stimuli vary only in place. Similar results are obtained when subjects are asked to classify the stimuli along the voicing dimension. By taking advantage of the "McGurk" effect (McGurk & MacDonald, 1976), the present study investigated whether a similar pattern of interference extends to situations in which variation along the place dimension occurs in the visual modality. The results showed that RTs for classifying phonetic features in the test condition were significantly longer than in the control condition for the place and voicing dimensions. These results indicate a mutual and symmetric interference exists in the classification of the two dimensions, even when the variation along the dimensions occurs in separate modalities.  相似文献   
74.
This is a preliminary report of a project designed to increase hope and quality of life (QOL) in older persons through a series of five training sessions. The training sessions for the experimental groups are based on research on happiness, goal imagery, and time management. Data indicates that the training is effective in increasing expected QOL. Several measures of affect and stress are examined as a function of three time frames of self-reported QOL. Daily uplifts are significantly related to present and future QOL while measures of stress and major life changes are not. Correlations of affective measures with QOL tend to increase from time frames of the past five years through the present to the next five years, indicating the relevance of hope for older persons. Training for increased hope works with older persons. Data obtained in the process is used to address theoretical models of QOL in older persons. This project was supported by a grant from the American Association of Retired Persons Andrus Foundation.  相似文献   
75.
The midlife phase in the marital relationship is a complicated transition period, challenging the flexibility and coping skills of every couple. Separation-Divorce Initiation (S/DI) at this time can serve a special function in the change process required in this stage. A comprehensive therapeutic model for S/DI couples is described. It includes (1) assessment of the relationship's stamina and the function of the S/DI; (2) treating symptoms and reactions to the traumatic event in an emergency intervention mode; (3) steps and techniques to help the couple overcome the traumatic effects of the SD/I and to rebuild their relationship on a more appropriate basis.  相似文献   
76.
The time course of memory decay for infant rats may shed light on the processes responsible for infantile amnesia. A taste aversion conditioning procedure appropriate for both neonatal and adult rats was employed in four experiments to investigate the ontogeny of extended retention. In Experiment 1, rats trained at 1, 10, 20, or 60 days of age were tested for retention of the taste aversion 25 days later. At testing, only those rats conditioned when 20 or 60 days old demonstrated significant taste aversions. Experiments 2 and 3 established that rats 14-15 days old and older were able to retain significant taste aversions following a 25-day retention interval. Younger rats did, however, acquire and retain the aversion for several days and showed a gradual retention loss over progressively longer retention intervals (Experiment 4). These findings suggest that preweanling rats demonstrate initial consolidation, storage, and retrieval of conditioned taste aversions. It is only after this initial period that retention deficits become evident.  相似文献   
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This study compared two levels of syntactic encoding with respect to their effect on aphasics' auditory comprehension. The same informational content was presented either as an embedded sentence or as two contiguous simplé propositions. A similar contrast was utilized to compare sentences containing relational terms of time, comparison, instrumentality, as well as sentences involving conjunction reduction, with parallel messages expressed in expanded, simplified form. A picture-verification paradigm was used. Comprehension was significantly enhanced only in the case of embedded sentences, with a tendency for Broca's aphasics to show the maximum effects.  相似文献   
80.
This research investigated rural high school students' perceptions of two major secondary school role models' (teachers and popular peers) solutions to five ontological and axiological problem spheres. The Values Orientation Questionnaire (VOQ), an operationalization of F. Kluckhohn's theory of intra-cultural value variation, was completed each of three times during three months: initially for the self and then according to the way the respondent felt the models would respond. Achievement, an index of successful school encounters, was entered as the between-persons factor in a multivariate-model repeated-measures ANCOVA. Generally, the students believe that teachers and popular peers endorse that set of values that forms the foundation of progressive counseling and educational philosophies and practices and is, to a large extent, our middle-class system. Students perceive teachers as overendorsing (relative to self) those ontological choices that form the valuational basis of authoritarian counseling and educational theories. These seemingly contradictory teachers' attributions are discussed in terms of the teachers' roles and of institutional demands that often force teachers to model behaviors that neither they nor society deems desirable.  相似文献   
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