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131.
Michael Bacharach 《Synthese》1992,91(3):247-284
According to decision theory, the rational initial action in a sequential decision-problem may be found by ‘backward induction’ or “folding back’. But the reasoning which underwrites this claim appeals to the agent's beliefs about what she will later believe, about what she will later believe she will still later believe, and so forth. There are limits to the ‘depth’ of people's beliefs. Do these limits pose a threat to the standard theory of rational sequential choice? It is argued, first, that the traditional solutions of certain games depend on knowledge which exceeds depth limits, and that these solutions therefore cannot be shown rational in the usual sense. Then, for that related reason even ‘folding back’ solutions of one-person problems cannot be! A revision of our notion of rational choice is proposed, analogous to the reliabilist account of knowledge of Goldman and others, by which this paradox is resolved. 相似文献
132.
The Companeros model of HIV infection prevention in Ciudad Juarez, Mexico, is presented as conceived by the National Institute of Drug Abuse (NIDA). 518 women who were IV drug users, sexual partners of drug addicts, or prostitutes were requested to participate, and 232 consented. Initial and follow-up AIDS assessments were utilized along with an assessment of sociodemographic variables, including knowledge, sexual behavior, use and abuse of drugs, and previous health history. Educative sessions about AIDs and sexually transmitted diseases (STDs) included group discussions and interaction, video watching, personal experiences, and sociodramas. 61% of prostitutes were 29, 12.6% were 13-19 years old, 31.1% were aged 30-39, and 8.9% were 40. 11% had no formal education, 58% had 6 years of primary and part of 3 years of secondary education, only 18.6% completed secondary education; and 13% had higher education. 19% lived in a hotel or shelter. Family disintegration reached 44%; these women did not live with their children. Only 5.2% thought they had excellent health, 51% said they had good health, 31% stated they had average health, and 12% admitted having had health problems. 14.6% had genital ulcers, 1.3% had herpes, 15% had gonorrhea, and 10% had syphilis. Since IV drug use among these women was almost nonexistent sexual relations constituted the principal risk factor. Responses to a questionnaire showed that the most frequent sexual behavior was vaginal penetration followed by fellatio; anal penetration was less common. 34.9% of the women practiced fellatio without protection, 16.3% had anal intercourse without protection. The proportion of AIDS cases in Mexico in women of reproductive age was growing at an exponential rate, possible because of misinformation about AIDS, a history of STDs, and a low rate of condom use. 相似文献
133.
Although visuoconstructive impairment has been reported in both Alzheimer's (DAT) and Huntington's (HD) disease, there is little knowledge concerning how this cognitive deficit differs quantitatively and qualitatively in these two progressive dementias. To address this issue, the present study compared performances on the Clock Drawing Test (CDT: command and copy) of 25 DAT patients, 25 equally demented HD patients, and 25 elderly normal controls (NC). In the command condition, both patients groups were significantly impaired compared to the NC group. Although there was no significant difference between DAT and HD patients' total quantitative scores, a qualitative error analysis revealed a number of dissociations between the two patient groups. Graphic difficulties, very common in HD patients, were virtually absent in DAT patients; in contrast, conceptual errors were almost exclusively seen in DAT patients and were related to the severity of their dementia. Perseveration and "stimulus-bound" responses were also more frequent in DAT patients, and both groups made visuospatial errors. In the copy condition, the DAT, but not the HD, patients evidenced a marked improvement in performance. These results indicate that while both DAT and HD patients have significant visuoconstructive difficulties even in the early stages of their disorders, the specific cognitive processes underlying their quantitative impairments are quite different. It is possible that the DAT patients' conceptual errors are yet another indicator of the deterioration of their semantic knowledge. 相似文献
134.
On the Relation Between Time Perception and the Timing of Motor Action: Evidence for a Temporal Oscillator Controlling the Timing of Movement 总被引:7,自引:0,他引:7
Michel Treisman Andrew Faulkner Peter L. N. Naish 《The Quarterly Journal of Experimental Psychology Section A: Human Experimental Psychology》1992,45(2):235-263
Studies of time estimation have provided evidence that human time perception is determined by an internal clock containing a temporal oscillator and have also provided estimates of the frequency of this oscillator (Treisman, Faulkner, Naish, & Brogan, 1992; Treisman & Brogan, 1992). These estimates were based on the observation that when the intervals to be estimated are accompanied by auditory clicks that recur at certain critical rates, perturbations in time estimation occur. To test the hypothesis that the mechanisms that underlie the perception of time and those that control the timing of motor performance are similar, analogous experiments were performed on motor timing, with the object of seeing whether evidence for a clock would be obtained and if so whether its properties resemble those of the time perception clock. The prediction was made that perturbations in motor timing would be seen at the same or similar critical auditory click rates. The experiments examined choice reaction time and typing. The results support the hypothesis that a temporal oscillator paces motor performance and that this oscillator is similar to the oscillator underlying time perception. They also provide an estimate of the characteristic frequency of the oscillator. 相似文献
135.
B. Michael Ferencik Ph.D. 《Group》1992,16(2):113-124
The essential activity of group therapy consists of members taking an interest in each other by asking questions, showing concern, and conveying understanding. When members have not done this it has often been taken as a sign of resistance. A review of the research on helping suggests that there are four social factors that affect assistance giving in groups: 1) ambiguity-often people fail to give help because they are uncertain about who should give it, what should be done, and how it should be done; 2) often help is not given because of the way in which problems are presented; 3) the social comparisons that individuals make affect help-giving; and 4) there are costs associated with providing assistance. This discussion suggests that leaders can facilitate interaction among group members as teachers who clarify and as indirect helpers who redirect concerns back to group members. 相似文献
136.
This study explored patterns emerging in videotaped sessions of group psychotherapy with seven outpatients of a large mental health facility. The 22 sessions spanned the 12th to 27th months of the group's existence. Group members had long histories (25–50 years) of symptoms characteristic of schizophrenia. Each session was rated on the Group Environment Scale. One session from a group in its earlier stages was also rated on the same instrument to give some indication of baseline patterns. Analyses of changes across the 15 months were not statistically significant. However, some GES subscales, including Cohesion, Independence, and Self-Discovery, showed relatively high mean levels across the 15-month period. These elevations are discussed as suggesting the codevelopment of orientations that have sometimes been viewed as incompatible and unattainable for schizophrenics. Interpreted clinically, the GES patterns help to elaborate recent findings about the relatively good success of long-term group therapy with such populations. The study, although merely suggestive, illustrates the potential for gleaning solid and clinically useful data from group psychotherapy research.The authors would like to thank Drs. Jill Rierdan, Nina Fieldsteel, Joseph Christy, and an anonymous reviewer for their suggestions, Kendra Bryant for serving as the reliability rater, and Janet Eltinge for her skilled videotaping. 相似文献
137.
N J Osgood 《Suicide & life-threatening behavior》1992,22(1):98-106
One major purpose of this study was to identify environmental factors related to suicide in long-term care facilities. Questionnaires were mailed to a random sample of administrators at 1,080 facilities. Information was collected on facility characteristics, overt suicide, and intentional life-threatening behavior. Chi-square analyses revealed 4 environmental characteristics related to suicidal behavior and deaths from suicide: staff turnover, size, auspices, and per diem cost. More suicides occurred in larger facilities and facilities with higher staff turnover. Religious or "other" facilities experienced more suicidal deaths than public or private facilities; facilities charging less experienced more deaths. 相似文献
138.
This study sought to investigate the effects of mild head injury on a particular type of cognitive ability, verbal analogical
reasoning. The performance of 19 individuals with head injuries was compared to a group of 30 control subjects matched for
age, education, and gender on 100 verbal analogies. Solution times and error rates were modeled. Unstandardized regression
weights for individual subjects were correlated with subjects’ performance on a number of standardized ability tests. Results
showed that compared to the control subjects, the head injured subjects: (a) were significantly slower to solve the analogies,
and were particularly slow to perform certain processes: encoding/inference and comparison; (b) tended to show greater variability
in performance; and (c) had data that had a poorer componential model fit. The data suggest that analogical reasoning is affected
by a head injury, and that certain information processes may be responsible for performance deficits. 相似文献
139.
Contemporary research on the construction of the self emphasizes the products rather than the process of self-development.
Borrowing from the writings of William James and contemporary views of natural selection, we propose a model ofevolutionary self-construction. Grounded in the principles of evolution and the philosophy of pragmatism, evolutionary self-construction proposes a process
that guides the seeking of “truth” inpossible selves. According to this view, the self develops in response to uncertainty reduction with the “correct” self identified
via the “sentiment of rationality.” Selves presently identified as correct are considered to be “instruments of action” that
facilitate the interaction between an individual and the environment. Selected selves can then be developed to one’s best
advantage and presented in an optimal fashion. This model helps organize contemporary frameworks around a common theme and
embraces affect as a central component in the development of the self.
A previous version of this paper was presented at the 98th annual meeting of the American Psychological Association, Boston,
MA. 相似文献
140.
N G Bliwise 《Psychology and aging》1992,7(1):83-88
Elderly women in subjectively good health--free of acute illness and major sleep pathologies--who were self-identified as good (n = 22) and poor (n = 16) sleepers were compared on measures of physical health, psychological symptoms, psychosocial status, and life-style. Poor sleepers reported longer sleep latencies, less total sleep time, more nonrestorative sleep, and more daytime fatigue than did good sleepers. Sleep recordings confirmed subjective reports, with shorter total sleep times and trends for lower sleep efficiency, longer sleep latencies, and more wake-after-sleep onset among women with subjective poor sleep. Poor sleepers also were more frequent users of sedative-hypnotic medications in the past. Current medication use, alcohol and caffeine use, daytime napping, and exercise were equivalent in both groups. Psychosocial status failed to discriminate groups. Poor sleepers reported significantly more psychological symptoms than did good sleepers. The levels of both psychological symptoms and sleep disturbance were mild. 相似文献