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151.
Temporal integration and vibrotactile backward masking   总被引:1,自引:0,他引:1  
Subjects were presented with vibrotactile target patterns to their left index fingertips. The target patterns varied in the number of line segments that they contained and were presented in the presence or absence of a backward-masking stimulus. The stimulus onset asynchrony (SOA) between the target and masker was varied. In an identification task, subjects' errors indicated that the effect of the masker at brief SOAs was to increase the perceived number of line segments in the target. This effect diminished with increasing SOA, and at the longest SOAs subjects confused targets with patterns containing the same number of line segments but varying in how the line segments were related. In an estimation task, the effect of the masker was to increase the number of line segments estimated to be contained in the target pattern. The effect of the masker at brief SOAs is discussed in terms of an integration theory of vibrotactile backward masking. At longer SOAs, the results suggest that the masker may interfere with the extraction of relational information in the target pattern.  相似文献   
152.
A homogeneous sample of normal adults living in a religious order in a study of age effects on reference as a cohesive device in discourse production and comprehension. Narrative and procedural discourse were examined across various levels of complexity and stimulus/response requirements. Results indicate that significant ambiguity of reference emerges in the younger elderly group (age 64-76) in comparison to the middle-aged group (age 27 to 55), and increases markedly in the older elderly group (age 77-92). Related impairments of comprehension and cognition were also observed. These findings are interpreted to be general features of linguistic variation with advancing age. Communicative consequences of ambiguous reference are discussed.  相似文献   
153.
Glucose effects on memory: behavioral and pharmacological characteristics   总被引:4,自引:0,他引:4  
Recent findings indicate that post-training glucose injections can modulate memory storage for inhibitory (passive) avoidance training. Experiment I extended these findings to determine whether glucose, like other memory modulating treatments, enhances memory storage when administered after training with low footshock and impairs memory storage after high footshock training. In Experiment I, male Sprague-Dawley rats were trained in a one-trial inhibitory avoidance task using either a brief footshock (0.5 mA, 0.7 s) or slightly more intense footshock kept on until escape (0.7 mA, mean escape latency = 3.4 s). Immediately after training, each rat received a subcutaneous injection of glucose (100 mg/kg). When tested for retention performance 24 h later, the glucose-injected animals exhibited enhanced retention performance for low footshock training and impaired retention for high footshock training. Experiment II determined whether pretreatment with adrenergic antagonists blocked the effects of glucose on memory. Pretreatment with the alpha- or beta-adrenergic receptor antagonists, phenoxybenzamine, or propranolol, respectively, had no effect on acquisition or retention in animals trained with the brief footshock and did not affect glucose facilitation of that memory. In animals trained to escape footshock, phenoxybenzamine did not attenuate the amnesia produced by glucose. Propranolol-pretreated animals had impaired retention whether or not they received post-training amnestic injections of glucose; glucose had no effect on retention in these amnestic animals. These findings add further support to the view that glucose release after training and treatment may represent a physiological response subsequent to epinephrine release in modulating memory storage processing.  相似文献   
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156.
The factors perceived as helpful by members of three different types of self-help groups are examined, using the 12 factors identified by Yalom as operative in group psychotherapy. Questionnaires were given to 45 members of self-help groups, asking for their views of the most and least helpful aspects of their experiences of their group, and for their judgement of its effectiveness. Results indicated that members of a group concerned with social and personal support in the face of a socially problematic situation (widowhood) found the experience of Universality to be the most helpful factor, while Self-Disclosure was least helpful. Members from a group for the physically sick (asthma sufferers) also reported the least helpful factor to be Self-Disclosure, but said that the most helpful factor was Guidance. By contrast, the group concerned with providing 'therapy' for depressives reported Cohesiveness to be most helpful, and Guidance to be least helpful. Comparison with other studies using similar methodologies with different group populations suggests that the factors likely to be effective in self-help groups for the socially unsupported and physically sick on the one hand, and for the psychologically disturbed on the other, may differ.  相似文献   
157.
James P. Henry 《Zygon》1986,21(1):47-74
Abstract. Established religions integrate a society's everyday secular realities with humankind's numinous experience of the holy. Powerful emotions nourish the cultural expression of the archetypes propelling the "ritual dances" of art, sport, and technocracy. During sacred moments such as mother-infant or adult bonding, neuroendocrine triggers activate lifelong ties. The cultural canon of the left cortex contrasts with the intuitive right. Brainstem "switches" alternate the left's cool, extraverted, sympathetic drive for control with the right's "warm" attachment behavior and dreaming sleep. Psychic trauma damages flexibility with resultant alexithymic blindness to emotions and archetypes. Substance abuse and narcissistic overemphasis on control ensue.  相似文献   
158.
Fluid intelligence belongs to that cluster of intellectual abilities evincing aging loss. To examine further the range of intellectual reserve available to aging individuals and the question of replicability in a new cultural and laboratory setting, 204 healthy older adults (mean age = 72 years; range = 60-86) participated in a short-term longitudinal training study. For experimental subjects, 10 sessions consisted of cognitive training involving two subability tests (Figural Relations, Induction) of fluid intelligence. The pattern of outcomes replicates and expands on earlier studies. Older adults have the reserve to evince substantial increases in levels of performance in fluid intelligence tests. Transfer of training, however, is narrow in scope. Training also increases accuracy of performance and the ability to solve more difficult test items. Difficulty level was estimated in a separate study, with a comparable sample of N = 112 elderly adults. Future research is suggested to examine whether intellectual reserve extends to near-maximum levels of performance.  相似文献   
159.
Short scales were developed to measure three broad dimensions of personality in the National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Followup Study. Items to measure neuroticism were selected rationally from the General Well-Being Schedule, and items to measure extraversion and openness to experience were selected by multiple regression from the NEO Personality Inventory. In a sample of 654 men and women from the Augmented Baltimore Longitudinal Study of Aging, all three short scales showed clear evidence of convergent and discriminant validity against full scales in self-reports, and against peer and spouse ratings. Because they were developed and validated on a sample with a comparable age range, the NHANES scales should be useful in examining age trends in these three personality dimensions in a national sample.  相似文献   
160.
The present study examined some previously reported relationships between drug use by adolescents and perceived attitudes and behaviors of their parents. An anonymous questionnaire was administered to the student body of an inner-city secondary school for difficult students. Relationships between parental use of drugs and adolescent use of the same drugs were moderate and roughly equivalent across drugs. However, parental use of marijuana was strongly related to the adolescent's use of other, harder drugs such as opiates, cocaine, amphetamines, and barbiturates. This finding is explained within the framework of Kandel's postulated stages of drug initiation. It points to a need for further study of parental influences, which may be increasingly problematic as more individuals who have grown up in our marijuana-accepting society become parents of adolescents.  相似文献   
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