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21.
The presence or absence of pulses of low intensity electric shock was used as a discriminative stimulus to control responding under fixed ratio reinforcement in the squirrel monkey. Initially brief periods of nonreinforcement were lengthened only when discriminative control was evident. Discriminative control was studied by (1) varying the duration of nonreinforcement periods; (2) reversing the stimulus conditions correlated with reinforcement and nonreinforcement periods; and (3) determining the minimum shock intensity necessary to maintain discriminative control. Stimulus control was not reliably affected by d-amphetamine, chlorpromazine, or morphine. The discriminative control by pulses of low intensity electric shock was similar to that by other discriminative stimuli, except that the control developed slowly and was better when the pulsing shock was correlated with reinforcement than when correlated with nonreinforcement.  相似文献   
22.
Single letters were presented for from one to five flashes, with S required to report what he saw after each flash. The clarity of the letter increased sharply with repetition. Since the letters were no larger than one-third of a degree in size, clarity could not have been increased by S making different fixations from flash to flash and combining them into a total percept. Nor was S guessing, since this could be ruled out by other indicators. Thus, it was concluded that repetition of the stimulus can have a direct effect on the clarity of a S’s percept of that stimulus.  相似文献   
23.
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
24.
Although lexical semantic deficits are postulated to play a prominent role in the anomia of Alzheimer's disease, it is unclear whether the primary disturbance is one of lexical access or one of lexical semantic loss. Response consistency on a naming task is one means of evaluating the underlying source of naming impairment. Access dysfunction usually implies variable word-finding difficulty, while a theory of lexical loss predicts that many word names would be consistently unavailable. Nineteen Alzheimer's disease patients were administered a visual confrontation naming task (the Boston Naming Test) on two occasions 6 months apart. Eighty percent of errors occurred consistently at both times; only 20% of errors occurred on only one occasion. Response consistency occurred significantly more often than expected under the assumption of no response consistency. Findings support the hypothesis that anomia in Alzheimer's disease is in part due to a loss of lexical semantic information.  相似文献   
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26.
How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
27.
Coping—competence theory yields a structural model of the development of persistent aggression in which current challenge encounters determine future life outcomes and competence. Driven by this model, universal, school-based prevention programs would aim in multiple ways to promote prosocial coping among high-risk, resilient, and advantaged youth from kindergarten through high school. Expected benefits of prosocial coping would include: less aggressive behavior, fewer adverse life outcomes (e.g., school dropout, police arrest, teen pregnancy, conduct, mood, and substance-use disorders), and a more competent self-definition and social reputation. Five stages are described that may prove useful in creating prosocial schools and neighborhoods supportive of youth in transition away from antisocial coping and deviant peers.  相似文献   
28.
Therapists are increasingly considering chemical addiction from a family systems perspective. Effects of chemical dependency upon the family are discussed and intervention approaches aimed toward assisting the family as families redefine themselves and change their structure are considered. The integration of chemical dependency treatment and the family therapy is also discussed as it is practiced in an intensive outpatient program at a psychiatric hospital.  相似文献   
29.
This review describes two clinically significant face processing deficits, prosopagnosia and Capgras delusion, and provides new knowledge about the face recognition process by a convergence of empirical findings. These empirical findings are structured around two questions that are viewed from the perspectives of the two deficits. First is the question of hemispheric specificity, which inquires into the degree of each hemisphere's contribution to the face recognition process. Second is the question of dual neural pathways, which addresses the possibility that the face recognition process proceeds along two parallel pathways in the brain. Findings from the hemispheric specificity studies reinforce the current view that right hemisphere involvement is necessary for face recognition while left hemisphere involvement is minimal. Findings from the dual neural pathways studies reinforce the plausible but yet unproven hypothesis that two neural pathways pass information from the visual association cortex in the occipital lobe toward the temporal lobes and limbic system when faces are seen and recognized. These findings, which also indicate that each of the dual neural pathways carries different, nonredundant information, could be instrumental in showing that the pathways play different roles in the manifestations of the clinically significant face processing deficits, prosopagnosia and Capgras delusion.  相似文献   
30.
Congenital bilateral absence of the vas deferens (CBAVD) occurs in approximately 1.3% of infertile males and is thought to be, in most cases, a primarily genital form of cystic fibrosis (CF). Fourteen males with CBAVD considering microsurgical sperm aspiration from the epididymis (MESA) and in vitro fertilization were seen for genetic counseling and screening for CF. To retrospectively evaluate these patients' perceptions of the counseling and screening information, we conducted structured telephone interviews to assess their recall of information about CF and its impact on their health concerns and reproductive plans. We found that, as the health implications of CF are abstract and not as important to patients as the diagnosis of CBAVD itself, patients tend to view their CF status primarily in terms of their reproductive potential. Retrospective analysis afforded us an opportunity to identify the psychosocial issues of most concern to this unique patient population.  相似文献   
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