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281.
Fruehwald S Frottier P Eher R Ritter K Aigner M 《Suicide & life-threatening behavior》2000,30(3):272-281
The absolute and relative frequency of suicides in jails and prisons in Austria over the 50 years from 1947 to 1996 is described. Important legislational changes regarding the criminal justice system are discussed with regard to possible consequences for the incidence of prisoners' suicides. Within the five decades a significant increase in the absolute numbers of jail and prison suicides was evident in spite of the considerable decrease in the total inmate population. Therefore, the suicide rate of inmates of correctional facilities increased significantly. Possible reasons for this phenomenon are discussed in relation to changes of the criminal law. 相似文献
282.
The study investigated whether the Simon effect, and its facilitation and interference components, shows up in reaction time (RT) or in movement time (MT), depending on the response strategy. Experiment 1 replicated a study by Hietanen and Rämä. Subjects had to press one of two lateralised keys in response to one of two stimuli. The stimuli were presented in the center (neutral condition) or to the left or right side (corresponding or non-corresponding conditions). To press the response key, a reaching movement was necessary, and both RT and MT were recorded. One group of subjects showed an RT facilitation effect and an MT interference effect. Another group of subjects showed both MT facilitation and MT interference effects. It was hypothesized that the two groups used different response strategies. In Exps. 2 and 3, the subjects were explicitly instructed to use the two strategies that were hypothesized for Exp. 1. The results showed that whether facilitation and interference manifest themselves in RT or MT depends on the response strategy adopted by the subjects. 相似文献
283.
The Simon effect is the performance advantage for spatially corresponding, compared to non-corresponding, target-response
ensembles when the location of the target is task irrelevant. In four experiments, we tested the predictions of the attention-shift
account of the Simon effect. In all experiments, subjects made choice responses with respect to the identity of a central
target that followed a spatially non-informative peripheral precue. The first experiment showed a Simon effect away from the
precue when the precue was a go/no-go signal: responses to spatially non-corresponding precue-response pairs were faster than
responses to spatially corresponding precue-response pairs. The results of the second experiment suggested that this “reverse”
Simon effect was not due to inhibition. In the third experiment, a secondary working memory task required the encoding, and
later recall, of “oddball” precues. Although the Simon effect was absent, larger Simon effects towards the precue (i.e., responses
were faster to spatially corresponding, compared to non-corresponding, precue-response ensembles) were correlated with poorer
performance on the memory task. In the last experiment, the identity of completely non-informative precues was congruent,
incongruent, or unrelated to the identity of the target. With precues that were unrelated to the identity of the target, there
was a Simon effect towards the precues. Conversely, the Simon effect occurred away from the precue when the identity of the
precue was related to that of the target. The findings suggest that a shift of attention alone is not sufficient to produce
the Simon effect. Rather, the shift of attention must originate from an intentionally defined object. The results are discussed
within a framework that integrates the attention-shift and referential-coding hypotheses.
Received: 2 December 1999 / Accepted: 23 March 2000 相似文献
284.
Younger and older adults listened to discourse in quiet and in conversational noise, before answering questions concerning the material. Some questions required listeners to recall specific details; others were of a more integrative nature. When the listening situation was adjusted for individual differences in hearing, younger and older adults were equally adept at remembering the gist of the passages in both quiet and in two levels of noise. The two age groups also did not differ with respect to memory for specific details when listening in quiet or in a moderate level of noise, even when required to perform a concurrent task. Only at the loudest noise level did younger adults tend to recall more detail than older adults. However, when no adjustments were made to compensate for the poorer hearing of older adults (all participants tested under identical listening conditions), older adults could not recall as much detail as younger adults, either in quiet or in noise. The results indicate that the speech-comprehension difficulties of older adults primarily reflect declines in hearing rather than in cognitive ability. 相似文献
285.
Memorizing while walking: increase in dual-task costs from young adulthood to old age 总被引:8,自引:0,他引:8
The dual task of memorizing word lists while walking was predicted to become more difficult with age because balance and gait are in greater need of "attentional resources." Forty-seven young (ages 20-30 years), 45 middle-aged (40-50), and 48 old (60-70) adults were trained to criterion in a mnemonic technique and instructed to walk quickly and accurately on 2 narrow tracks of different path complexity. Then. participants encoded the word lists while sitting, standing, or walking on either track; likewise, speed and accuracy of walking performance were assessed with and without concurrent memory encoding. Dual-task costs increased with age in both domains; relative to young adults, the effect size of the overall increase was 0.98 standard deviation units for middle-aged and 1.47 standard deviation units for old adults. It is argued that sensory and motor aspects of behavior are increasingly in need of cognitive control with advancing age. 相似文献
286.
Genetically informative longitudinal data on self-reported symptoms of depression allow for an investigation of the causes of stability and change in depression symptoms throughout adult life. In this report, the authors investigated the relative contribution of genetic and environmental influences to symptoms of depression in 83 monozygotic and 84 dizygotic male twin pairs from the National Heart, Lung, and Blood Institute (NHLBI) Twin Study. Participants first completed the Center for Epidemiologic Studies-Depression (CES-D) scale in 1985-1986 and again during 1995-1997. Mean age of twins at baseline was 63 years, range 59 to 70. From cross-sectional genetic analyses we estimated the heritability of CES-D to be 25% (95% confidence interval [CI], 11%-39%) at baseline and 55% (95% CI, 40%-71%) at follow-up. Fitting longitudinal genetic models to the two-wave data, we found that stability of symptoms over the 10-year follow-up was due primarily to continuity of genetic influences. 相似文献
287.
Cross-sectional studies have found older adults to have lower levels of emotional distress after natural disasters. The maturation hypothesis suggests that older adults are less reactive to stress events, whereas the inoculation hypothesis argues that prior experience with disaster is protective. One hundred and sixty-six adults aged 30 to 102 were interviewed regarding the 1994 Northridge earthquake. Longitudinal data were available on depressed mood before and after the earthquake. The maturation hypothesis was generally not supported. The young-old were least depressed; however, this age difference was present prior to the earthquake. The old-old showed lowest levels of earthquake-specific rumination, but age did not buffer the relationship between damage exposure and rumination. The inoculation hypothesis was supported for depressed mood. Prior earthquake experience was related to lower postearthquake depression scores. 相似文献
288.
Grasping visual illusions: no evidence for a dissociation between perception and action 总被引:11,自引:0,他引:11
Neuropsychological studies prompted the theory that the primate visual system might be organized into two parallel pathways, one for conscious perception and one for guiding action. Supporting evidence in healthy subjects seemed to come from a dissociation in visual illusions: In previous studies, the Ebbinghaus (or Titchener) illusion deceived perceptual judgments of size, but only marginally influenced the size estimates used in grasping. Contrary to those results, the findings from the present study show that there is no difference in the sizes of the perceptual and grasp illusions if the perceptual and grasping tasks are appropriately matched. We show that the differences found previously can be accounted for by a hitherto unknown, nonadditive effect in the illusion. We conclude that the illusion does not provide evidence for the existence of two distinct pathways for perception and action in the visual system. 相似文献
289.
These studies examined the role of spatial encoding in inducing perception-action dissociations in visual illusions. Participants were shown a large-scale Müller-Lyer configuration with hoops as its tails. In Experiment 1, participants either made verbal estimates of the extent of the Müller-Lyer shaft (verbal task) or walked the extent without vision, in an offset path (blind-walking task). For both tasks, participants stood a small distance away from the configuration, to elicit object-relative encoding of the shaft with respect to its hoops. A similar illusion bias was found in the verbal and motoric tasks. In Experiment 2, participants stood at one endpoint of the shaft in order to elicit egocentric encoding of extent. Verbal judgments continued to exhibit the illusion bias, whereas blind-walking judgments did not. These findings underscore the importance of egocentric encoding in motor tasks for producing perception-action dissociations. 相似文献
290.
This study examined individuals' memory for the temporal order of autobiographical events and for the components that constitute autobiographical events. Study 1 measured performance on an across-event ordering task that involved the chronological arrangement of cards that displayed event labels. Results indicated poor ordering ability across events, but a reasonable ability to order clusters of events. Study 2 compared within-event and across-event ordering using computer-presented digital photographs. Participants were better at ordering the photographs in their own across-event trials than in their within-event trials. The results are discussed in terms of the retrieval of temporal information under within- and across-event conditions. 相似文献