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11.
Using a simple videogame, the effect of ethnicity on shoot/don't shoot decisions was examined. African American or White targets, holding guns or other objects, appeared in complex backgrounds. Participants were told to "shoot" armed targets and to "not shoot" unarmed targets. In Study 1, White participants made the correct decision to shoot an armed target more quickly if the target was African American than if he was White, but decided to "not shoot" an unarmed target more quickly if he was White. Study 2 used a shorter time window, forcing this effect into error rates. Study 3 replicated Study 1's effects and showed that the magnitude of bias varied with perceptions of the cultural stereotype and with levels of contact, but not with personal racial prejudice. Study 4 revealed equivalent levels of bias among both African American and White participants in a community sample. Implications and potential underlying mechanisms are discussed.  相似文献   
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13.
A closer look at unicellular organisms and their behavior as autonomous and social beings sheds new light on the nature of cognition. This allows, at the same time, a search for minimal conditions that help to identify the yet unknown appearance of cognition during evolution. Positive results might also serve as principles for the construction of intelligent artefacts as striven for in artificial intelligence and cognitive robotics research. Analyzing the abilities of prokaryotes and unicellular eukaryotes and comparing them to the abilities of "higher" organisms, we conclude that common definitions of cognition are not specific enough. The attempt to define cognition by focusing on the coupling between stimulus and response and asserting that (to have cognition) it has to be indirect and modifiable fails, simply because in all organisms every reaction to a stimulus is indirect and modifiable. A definition of cognition based on such a distinction cannot hold unless one is willing to ascribe cognitive capacities also to Escherichia coli bacteria, for instance. Viewing cognition as the sum of abilities necessary for coping with a complex physical and social environment is also highly questionable, i.e. unspecific. We show that functions comparable to the cognitive functions "perception" and "memory" in higher organisms can well be identified in unicellular beings. The "architecture" of the bacterial (prokaryotic) sensorimotor apparatus is also in some structures, but particularly at the functional level, comparable with that of higher organisms and should be, as a consequence, indicative of cognition. Furthermore, we discuss other, somewhat more delimitable, phenomena like detection of identity, counting, adaptation, habituation and learning in ethological categories and compare them to findings from the microorganismic world. In this context, we argue that so-called "true learning" and the appearance of nervous systems are not break-points in the evolution of cognition. The presence of nervous systems means only a huge amplification of the recognition power of individual organisms. The molecular net that realizes the regulation and transduction of signals in unicellular beings is comparable to the processes within a neural net, and a population of unicellular organisms can be viewed as an individual, multicellular net with amplified recognition power. Finally, we show that sophisticated forms of cooperation and competition developed also in populations of unicellular organisms. This seems not to be true for the phenomena imagination (rehearsal) and introspection, also to be seen as stemming from social problem-solving needs. As for these aspects, further research is needed, however, to put them on firm scientific grounds. Zusammenfassung. Eine genaue Betrachtung einzelliger Lebewesen und ihres Verhaltens als autonome und soziale Wesen wirft neues Licht auf die Natur von Kognition. Das erlaubt gleichzeitig eine Suche nach minimalen Bedingungen, die bei der Bestimmung des Erscheinens von Kognition in der Evolution helfen. Positive Ergebnisse könnten auch als Prinzipien für die Konstruktion intelligenter Artefakte dienen, wie sie in der Künstlichen Intelligenz und der kognitiven Robotikforschung angestrebt werden. Ein Vergleich der Fähigkeiten von Einzellern mit denen von "höheren" Organismen führt uns zu dem Schluß, daß gängige Definitionen von Kognition nicht spezifisch genug sind. Der Versuch, Kognition über die Indirektheit und Modifizierbarkeit der Kopplung zwischen Reiz und Reaktion zu definieren, scheitert, weil in allen Organismen Reiz-Reaktionsverbindungen indirekt und modifizierbar sind. Eine solche Definition ist nicht haltbar, es sei denn, man ist bereit, z.B. auch Escherichia coli-Bakterien kognitive Eigenschaften zuzubilligen. Die Definition von Kognition als Summe der Eigenschaften, die notwendig sind, um in einer komplexen physikalischen und sozialen Umgebung zu bestehen, ist ebenfalls hinterfragbar und unspezifisch. Wir zeigen, daß Leistungen, die mit den Kognitionsleistungen "Wahrnehmung" und "Gedächtnis" in höheren Organismen vergleichbar sind, in Einzellern nachweisbar sind. Die sensomotorische Komplexität von Einzellern ist auch in vieler Hinsicht strukturell, vor allem aber funktionell vergleichbar mit derjenigen höherer Organismen und kann deshalb als ein Hinweis auf Kognition gewertet werden. Darüber hinaus diskutieren wir andere, abgrenzbare Phänomene, wie Erfassung von Identität, Zählen, Adaptation, Habituation und Lernen, aus der Sicht der Verhaltensforschung und vergleichen sie mit Befunden aus der Welt der Mikroorganismen. In diesem Zusammenhang bestreiten wir, daß sogenanntes "echtes Lernen" und das Erscheinen von Nervensystemen Bruchstellen in der Evolution von Kognition sind. Die Anwesenheit von Nervensystemen bedeutet nur den Übergang von Systemen mit einem relativ begrenzten (Erkennungs-) Potential zu solchen mit einem riesigen Potential. Das molekulare Netz, das die Regulation und Transduktion von Signalen in Einzellern realisiert, ist vergleichbar mit den Prozessen innerhalb eines Nervennetzes. Eine Population von einzelligen Organismen kann als individuelles, multizelluläres Netz mit erhöhtem Erkennungspotential angesehen werden. Schließlich zeigen wir, daß raffinierte Formen von Kooperations- und Konkurrenzverhalten auch in Einzellerpopulationen vorhanden sind. Eine ähnliche Aussage scheint nicht für Phänomene wie Imagination (Probehandeln) und Introspektion möglich zu sein, die auch im Zusammenhang mit der Bewältigung sozialer Probleme zu sehen sind. Eine genaue naturwissenschaftliche Erfassung solcher Aspekte, die erst einen Vergleich zwischen Mehrzellern und Einzellern erlauben würde, ist allerdings noch zu leisten.  相似文献   
14.
We used a comprehensive longitudinal data set from Germany to examine trajectories of symptom distress depending on interpersonal problems at study intake measured via the Inventory of Interpersonal Problems-64 (IIP-64; Horowitz, Strau, & Kordy, 1994). Participants (N=622) underwent mid- or long-term outpatient psychotherapy (either psychodynamically oriented psychotherapy, cognitive behavioral therapy, or analytic psychotherapy). Data comprises up to 5 assessments during a 2-year period and was analyzed via hierarchical linear modeling. In the analytic psychotherapy subgroup, initial symptom level was higher in submissive patients. Initial interpersonal problems were not predictive of the rate of symptom change during therapy. Only in psychodynamic treatments, low affiliation positively affected treatment outcome. Interpersonal problems at intake were not related to the number of utilized sessions and utilization rate across treatment subgroups. We discuss the findings and outline future research topics.  相似文献   
15.
The role of locomotion in the acquisition and transfer of spatial knowledge was investigated in 144 five-, seven- and eleven-year-old children. Two experiments were conducted in the Kiel locomotor maze. In the first experiment, one group of children explored the spatial layout by walking through the maze, while another learned the maze by surveying the layout. In the second experiment, children were exposed to one of two orientation tests in the maze, one of which could be solved using "landmark orientation", the other only using a "relational place orientation". Children sitting by the side of the experimental chamber surveying the maze needed fewer trials to learn the spatial layout than children exploring the environment in the locomotion condition, but in the orientation test demanding the "relational place orientation" children who had explored the maze in the locomotion condition outperformed the children in the non-locomotion condition. Results are discussed in the context of cognitive mapping models.  相似文献   
16.
Cross-sectional differences and longitudinal changes in cognitive functioning in relation to mortality across a 7-year follow-up period, with 3 times of measurement, were examined in a population-based sample of very old adults. The authors also sought to determine whether cause of death (cerebro/cardiovascular disease [CVD]; non-CVD) modified the magnitude of mortality-related cognitive deficits. Cognitive performance was indexed by tests of general cognitive ability, episodic memory, primary memory, verbal fluency, and visuospatial ability. Results indicated cross-sectional differences on all domains of functioning, with persons who would die within 3 years after baseline testing performing more poorly. Longitudinally, greater decrements were observed on all domains for persons who would die after the first follow-up period, as compared with survivors. Cause of death failed to modify the magnitude of the cross-sectional and longitudinal deficits. The pattern of results point to the general nature of this phenomenon.  相似文献   
17.
Five competing models specifying the factor structure underlying the Wechsler Memory Scale-Third Edition (D. Wechsler, 1997b) primary subtest scores were evaluated in a sample of patients with intractable temporal lobe epilepsy (N = 254). Models specifying separate immediate and delayed constructs resulted in inadmissible parameter estimates and model specification error. There were negligible goodness-of-fit differences between a 3-factor model of working memory, auditory memory, and visual memory and a nested--more parsimonious--2-factor model of working memory and general memory. The results suggest that specifying a separate visual memory factor provides little advantage for this sample--an unexpected finding in a population with lateralized dysfunction, for which one might have predicted separate auditory and visual memory dimensions.  相似文献   
18.
Orientation and navigation in a complex environment requires path planning and recall to exert goal-driven behavior. Walking Drosophila flies possess a visual orientation memory for attractive targets which is localized in the central complex of the adult brain. Here we show that this type of working memory requires the cGMP-dependent protein kinase encoded by the foraging gene in just one type of ellipsoid-body ring neurons. Moreover, genetic and epistatic interaction studies provide evidence that Foraging functions upstream of the Ignorant Ribosomal-S6 Kinase 2, thus revealing a novel neuronal signaling pathway necessary for this type of memory in Drosophila.  相似文献   
19.
The goals of the present study were to assess the interrelationships among tasks from the MATRICS and CNTRACS batteries, to determine the degree to which tasks from each battery capture unique variance in cognitive dysfunction in schizophrenia, and to determine the ability of tasks from each battery to predict functional outcome. Subjects were 104 schizophrenia patients and 132 healthy control subjects recruited as part of the CNTRACS initiative. All subjects completed four CNTRACS tasks and two tasks from the MATRICS battery: Brief Assessment of Cognition in Schizophrenia Symbol Coding and the Hopkins Verbal Learning Test. Functional outcome was also assessed in the schizophrenia subjects. In both the patient and control groups, we found significant intercorrelations between all higher order cognitive tasks (episodic memory, goal maintenance, processing speed, verbal learning) but minimal relationships with the visual task. For almost all tasks, scores were significantly related to measures of functional outcome, with higher associations between CNTRACS tasks and performance-based measures of function and between one of the MATRICS tasks and self-reported functioning, relative to the other functioning measures. After regressing out variance shared by other tasks, we continued to observe group differences in performance among task residuals, particularly for measures of episodic memory from both batteries, although these residuals did not correlate as robustly with functional outcome as raw test scores. These findings suggest that there exists both shared and specific variance across cognitive tasks related to cognitive and functional impairments in schizophrenia and that measures derived from cognitive neuroscience can predict functional capacity and status in schizophrenia.  相似文献   
20.
This prospective study investigated the personal growth of Israeli mothers of premature babies at two medically defined risk levels (infants at low risk, n = 42; infants at moderate-high risk, n = 52), examining the contribution to the five dimensions of personal growth of objective event characteristics (baby’s risk level), perceived levels of mother’s stress (linear and curvilinear associations), and mother’s personal resources (self-esteem, attachment styles, perceived emotional support from her own mother). In addition, the role of the event severity as a moderator of the association between perceived maternal emotional support and personal growth was explored. Findings indicate that mothers in the two risk groups did not differ in level of perceived stress. Mothers of infants at moderate-high risk, however, experienced more spiritual change. In addition, consistent curvilinear associations emerged between perceived levels of stress and personal growth for three dimensions of growth: new possibilities, personal strength, and relations with others (with a similar trend for appreciation of life). Thus, mothers reporting moderate stress levels experienced the highest personal growth. Finally, risk group played a moderating role in the association between perceived maternal emotional support and personal growth on the dimensions of new possibilities, personal strength, and relations with others. On these dimensions, only among mothers of low-risk babies were higher levels of maternal emotional support associated with greater personal growth. The results highlight the importance of the subjective experience and the value of maternal emotional support for the personal growth of mothers of preterms. These findings may help in designing measures to identify populations at risk and developing appropriate interventions, as well as impact on the working procedures and support currently offered in most neonatal intensive care units.  相似文献   
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