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991.
To test the idea that scopolamine provides a suitable pharmacological model of the memory defects associated with cortical or subcortical dementias, we assessed memory on a battery of tasks in healthy young normal subjects who received 0.5 mg scopolamine, 0.1-0.2 mg glycopyrrolate or physiological saline, once each on three separate occasions, and compared the pattern of memory failure induced by scopolamine to that observed on the same tasks in patients with Alzheimer's disease (AD) or Huntington's disease (HD). In agreement with previous reports, scopolamine impaired acquisition and delayed recall of a 14-word list and disrupted retention on the Brown-Peterson distractor task, whereas the peripherally active anticholinergic glycopyrrolate was without effect. However, under scopolamine the pattern of errors made on these memory tasks was quite different from that seen in patients with AD. Scopolamine did not increase the number of false positive errors on delayed recognition of the word list and also failed to increase the number of prior-item intrusions on the Brown-Peterson task. Also, scopolamine did not impair learning of a symbol-digit paired-associate task, and did not reduce the number of words retrieved or increase the number of words repeated on a standardized verbal fluency test. When the effects of scopolamine on memory were compared to the pattern of impairments observed in demented patients with HD, several differences were found. Although scopolamine clearly produces deficits on some measures of anterograde memory, the present findings question whether anticholinergic drugs adequately mimic the full range of memory impairments observed in cortical or subcortical dementias.  相似文献   
992.
Contrast effects were obtained in rats in the consumption of saccharin solutions in three different paradigms. Degree of negative contrast varied as a function of concentration disparity, but not equally in the three procedures. Successive negative contrast occurred following shifts from 0.15% to either 0.075% or 0.05% saccharin but did not occur following shifts to 0.10% or 0.125% saccharin. Some degree of simultaneous contrast was obtained with all four concentration disparities. Anticipatory contrast, where the intake of the first substance is suppressed by a more preferred second substance, occurred only in the case of the 0.05%-0.15% difference in concentrations. It was suggested that the several contrast paradigms engage somewhat different psychological processes differentially involving emotional, sensory, and associative mechanisms, but all lead to behavior based on relative value. A modification of Toates's (1981) incentive model of ingestive behavior was suggested to incorporate relativity effects based on both associative and nonassociative factors in the consumption of both nutritive and nonnutritive substances.  相似文献   
993.
Saline-treated and amphetamine-treated (7 mg/kg, ip, immediate) male rats from a Sprague-Dawley substrain were observed in two test environments designed to elicit different investigative responses in normal rats. Snout contact with the substrate was generated by placing the rat in a small enclosed cage. Absence of snout contact was induced by placement of the rat on a square elevated platform. Detailed ethological records were kept of locomotion, rearing, sitting, grooming, gnawing, and sleeping throughout the 90-min session. Amphetamine-treated rats incorporated environmentally contingent bodily postures into their forms of stereotyped behavior. The postures were characteristic of those evinced initially by the saline-treated rats in the same test environment. The control rats showed appropriate changes in their investigative behavior when the apparatus was changed at 10 and at 30 min postinjection. The amphetamine-treated rats, however, were completely unresponsive to such changes at 30 min and only partially so at 10 min postinjection. It was concluded that there is a temporal gradient of decreasing readiness to modify repetitive behavior after a single, large dose of amphetamine.  相似文献   
994.
Two basic assumptions of the Circumplex Model of family systems were evaluated: (1) Healthy families evidence balanced degrees of cohesion and adaptability, whereas problem families evidence extreme degrees, and (2) families with balanced degrees of cohesion and adaptability possess more positive communication skills than families with extreme degrees. Subjects were 58 mother-son dyads from father-absent families. In 29 of the families the adolescent was a juvenile offender, while in the remaining families there was no history of arrest or psychiatric referral. The dyads completed the Family Adaptability and Cohesion Scales (FACES) and an unrevealed differences interaction task. FACES was highly proficient at differentiating delinquent from nondelinquent families. Moreover, in families with balanced degrees of cohesion and adaptability, the mothers' communication was significantly more supportive and explicit, and the dyads evidenced significantly greater warmth and affection than dyads with extreme degrees.This research was supported by funding to the Department of Psychology at Memphis State University granted through the Centers of Excellence Program of the State of Tennessee. We thank the staff of the Memphis-Metro Youth Diversion Project for their consideration and assistance.  相似文献   
995.
Peter C. Fishburn 《Synthese》1986,67(2):361-368
Axiomatizations of ordered preference differences typically assume that preferences are ordered. However, the mere assumption that preference differences can be ordered says nothing about whether preferences themselves are ordered. Utility representations for ordered differences without ordered preferences are investigated.  相似文献   
996.
997.
Quality-of-life measures: hospital interview versus home questionnaire   总被引:2,自引:0,他引:2  
Measures adapted from social survey research were used to assess the quality of life of 33 end-stage renal disease (ESRD) patients in a 2-week test-retest design that varied both location and format of administration (hospital interview vs. home self-administered questionnaire). The measures were found to have substantial consistency over time, location, and format. These results indicate that quality of life is a stable construct and support the usefulness of questionnaire quality-of-life measures for evaluating medical interventions.  相似文献   
998.
After critically examining the concept of psychopathy and reviewing the major existing theories of psychopathy in the light of a psychobiological conception of abnormal behaviour (Öhman, 1981), this paper attempts to present an integrated, psychobiological model of psychopathy. Essentially this analyses psychopathy in terms of the predisposing influences, the triggering environmental events which initiate psychopathic behaviour, and the neurophsychological mechanisms which mediate it. It is suggested that individuals who show chronic antisocial behaviour, conforming to the North American term ‘sociopath’, may demonstrate a maturational deficit but do not necessarily show a psychopathic personality disorder. The latter is said to be characterised, at a personality trait level, by high Impulsiveness and Psychopathy (Blackburn, 1982 a, b), reflecting interactive deficits in goal direction and affect. At a dynamic (state) level, a psychopathic personality disorder is said to be characterised by a lack of coping, reflecting either, in the case of the secondary psychopath, a deficit in primary appraisal, (over-perception of threat), or in the case of the primary psychopath, a deficit in secondary appraisal (low perceived control over aversive environmental events). It is further suggested that a genetic predisposition to social withdrawal and exposure to an uncontrollably aversive early environment may interact to predispose an individual to develop a psychopathic personality disorder in adulthood.  相似文献   
999.
Twenty-six previous studies were reviewed which demonstrated a consistent link between children's smoking uptake and exposure at home to an actively smoking older family member. The present study included another variable: the family model of smoking cessation. The smoking practices, intentions, and attitudes of 344 children aged 10–14 in Western Australia were anonymously assessed. Those with ex-smokers but no active smokers at home resembled children who had never been exposed to a smoking family model in being less likely to smoke now or intend to in the future, having fewer smoking chums, and believing that cigarettes had more personal and social disadvantages than their peers who shared households with active smokers. This suggested that any pro-smoking modeling while the ex-smoker was active had been counteracted by modeling of quitting. Implications for intervention were discussed.  相似文献   
1000.
Social reciprocity behavior was compared for handicapped and nonhandicapped preschool children when they were in play situations with both handicapped and nonhandicapped partners. In a counterbalanced design, handicapped and nonhandicapped children were paired with both handicapped and nonhandicapped play partners, and the social initiation and response sequences of the dyads were observed. Types of initiation observed were friendly statements, friendly questions, mildly negative advances, and demanding statements. Friendly, ignoring, and negative responses were observed to these initiations. Handicapped and nonhandicapped children did not differ on overall number of initiations. However, they did differ on the types of initiation they made. Handicapped children asked fewer friendly questions and engaged in more demanding initiations than expected. Both groups made more initiations when paired with handicapped partners than when paired with nonhandicapped partners, but the groups did not differ on the types of initiation made to handicapped and nonhandicapped partners. The handicapped children made more ignoring and negative responses to friendly initiations than the nonhandicapped children. Behaving similarly, both groups tended to respond negatively to negative and demanding initiations.  相似文献   
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