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The recent anniversary of the 1965 Swampscott Conference provided an opportunity to reconsider the implications of that meeting for prevention research. An unfulfilled aspect of the Swampscott legacy is the relative paucity of demonstration programs that become enduring parts of their host settings. A macrolevel, systems-oriented reformulation of Albee's (1982) prevention formula is presented to help conceptualize the linkage of prevention programs to their host settings. Finally, structural considerations necessary for weaving efforts at prevention and health promotion into adaptive, enduring organizational niches are reviewed.  相似文献   

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Human visual recognition on the basis of shape but regardless of size was investigated by reaction time methods. For successive matching of random figures, reaction time increased linearly with the linear size ratio of stimulus pairs. For single-character classification, reaction time increased with divergence between cued size format and stimulus format such that for character nonrepetitions, the increment in latency was approximately proportional to the logarithm of the linear size ratio of the two formats. However, when reactions to character repetitions were faster than those to nonrepetitions, the repetition reaction time function was similar to that for successive matching of random figures. The results suggested two processes of size scaling: mental-image transformation and perceptual-scale transformation. Image transformation accounted for matching performance based on visual short-term memory, whereas scale transformation accounted for size invariance in recognition based on comparison against visual representations in long-term memory.  相似文献   

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Global precedence in visual pattern recognition   总被引:3,自引:0,他引:3  
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In the experiments described in this paper we examined the effects of contextual stimuli on pigeons’ recognition of visual patterns. Experiment z showed acontext-superiority effect. Specifically, two target forms that were identical except for location in the visual field were not discriminated when presented alone, but the compounds formed when each of these targets was placed between a nearby pair of flanking stimuli were readily discriminated. The size of the context-superiority effect decreased with increasing target-flanker separation. In Experiments 2 and 3 the two targets differed in form rather than spatial location and were readily discriminated in the absence of Hankers. Under these circumstances, adding an identical pair of flankers to each target resulted in a content-inferiority effect; that is, the two target-plus-Hankers compounds were less readily discriminated than the targets atone. The size of the context-inferiority effect decreased with increasing target-flanker separation. The observed effects of context are predictable from the Heinemann-Chase (1990) model of pattern recognition.  相似文献   

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Visual object recognition is considered to be largely translation invariant. An earlier study (Foster & Kahn, 1985), however, has indicated that recognition of complex novel stimuli is partially specific to location in the visual field: It is significantly easier to determine the identity of two briefly displayed random patterns if both stimuli are presented at the same, rather than at different, locations. In a series ofsame/different discrimination tasks, we characterize the processes underlying this “displacement effect”: Horizontal and vertical translations are equally effective in reducing performance. Making the task more difficult by increasing pattern similarity leads to even higher positional specificity. The displacement effect disappears after rotation or contrast reversal of the patterns, indicating that positional specificity depends on relatively low levels of processing. Control experiments rule out explanations that are independent of visual pattern memory, such as spatial attention, eye movements, or retinal afterimages. Positional specificity of recognition is found only forsame trials. Our results demonstrate that position invariance, a widely acknowledged property of the human visual system, is limited to specific experimental conditions. Normalization models involving mental shifts of an early visual representation or of a window of attention cannot easily account for these findings.  相似文献   

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It is frequently claimed that the influence of behaviorism in general and of B. F. Skinner in particular, is declining. Data obtained from the Social Sciences Citation Index for the years 1966-1989 document that in the last twenty-four years the number of citations to the works of Skinner has been reasonably steady. There is no evidence of a decline in the absolute number of such citations, suggesting that claims of the demise of behaviorism may be, once again, premature.  相似文献   

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The learning process related to pattern and object recognition is difficult to study because the human brain has a remarkable capacity to recognise complex visual forms from early infancy. In the present study, we investigated on-going neural changes underlying the learning process of visual pattern recognition by means of a device substituting audition for vision. Functional MRI evidenced the gradual pattern recognition-induced recruitment of the ventral visual stream, bilaterally, from learning session 1 to session 3, and a slight decrease in these activation foci from session 3 to session 4. The initial increase in activation is thought to reflect the gradually enhanced visualisation of patterns in the subjects' mind across sessions. By contrast the subsequent decrease reported at the end of the training period is interpreted as the progressive optimisation of neuronal responses elicited by the task. Our results, in accordance with previous observations, suggest that the succession of activation increase and decrease in sensori-motor areas could be a general rule in sensory and sensori-motor learning.  相似文献   

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Three experiments assessed the contributions of age-of-acquisition (AoA) and frequency to visual word recognition. Three databases were created from electronic journals in chemistry, psychology and geology in order to identify technical words that are extremely frequent in each discipline but acquired late in life. In Experiment 1, psychologists and chemists showed an advantage in lexical decision for late-acquired/high-frequency words (e.g. a psychologist responding to cognition) over late-acquired/low-frequency words (e.g. a chemist responding to cognition), revealing a frequency effect when words are perfectly matched. However, contrary to theories that exclude AoA as a factor, performance was similar for the late-acquired/high-frequency and early-acquired/low-frequency words (e.g. dragon) even though their cumulative frequencies differed by more than an order of magnitude. This last finding was replicated with geologists using geology words matched with early-acquired words in terms of concreteness (Experiment 2). Most interestingly, Experiment 3 yielded the same pattern of results in naming while controlling for imageability, a finding that is particularly problematic for parallel distributed processing models of reading.  相似文献   

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Empirical work and models of visual word recognition have traditionally focused on group-level performance. Despite the emphasis on the prototypical reader, there is clear evidence that variation in reading skill modulates word recognition performance. In the present study, we examined differences among individuals who contributed to the English Lexicon Project (http://elexicon.wustl.edu), an online behavioral database containing nearly 4 million word recognition (speeded pronunciation and lexical decision) trials from over 1,200 participants. We observed considerable within- and between-session reliability across distinct sets of items, in terms of overall mean response time (RT), RT distributional characteristics, diffusion model parameters (Ratcliff, Gomez, & McKoon, 2004), and sensitivity to underlying lexical dimensions. This indicates reliably detectable individual differences in word recognition performance. In addition, higher vocabulary knowledge was associated with faster, more accurate word recognition performance, attenuated sensitivity to stimuli characteristics, and more efficient accumulation of information. Finally, in contrast to suggestions in the literature, we did not find evidence that individuals were trading-off their utilization of lexical and nonlexical information.  相似文献   

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Two priming experiments using a perceptual identification task were conducted to explore the functional and representational overlap between visual imagery and visual perception. The first experiment included a study phase in which primes were either perceived or imaged objects and a perceptual identification test task in which targets were parts of studied and non-studied objects. Imagery primed identification when subjects were instructed to count the parts of the imaged objects in the study phase but not when they were instructed to focus on the global shape of the imaged objects. This result suggests that imagery involves perceptual representations identical to those involved in perception. It also suggests that the representational overlap between imagery and perception depends on the type of images generated, as some images may consist in global shapes only, whereas others may consist in detailed, multi-part shapes. In the second experiment, we used whole objects as target stimuli which provided subjects with more information to identify masked targets and thereby reduced top-down processing. Priming from imagery fell beneath significance, suggesting that this sort of priming is elicited in a large part by a transfer of top-down processes from study to test.  相似文献   

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The extent to which readers can exert strategic control over oral reading processes is a matter of debate. According to the pathway control hypothesis, the relative contributions of the lexical and nonlexical pathways can be modulated by the characteristics of the context stimuli being read, but an alternative time criterion model is also a viable explanation of past results. In Experiment 1, subjects named high- and low-frequency regular words in the context of either low-frequency exception words (e.g., pint) or nonwords (e.g., flirp). Frequency effects (faster pronunciation latencies for high-frequency words) were attenuated in the nonword context, consistent with the notion that nonwords emphasize the characteristics of the frequency-insensitive nonlexical pathway. Importantly, we also assessed memory for targets, and a similar attenuation of the frequency effect in recognition memory was observed in the nonword condition. Converging evidence was obtained in a second experiment in which a variable that was more sensitive to the nonlexical pathway (orthographic neighborhood size) was manipulated. The results indicated that both speeded pronunciation performance and memory performance were relatively attenuated in the low-frequency exception word context in comparision with the nonword context. The opposing influences of list context type for word frequency and orthographic neighborhood size effects in speeded pronunciation and memory performance provide strong support for the pathway control model, as opposed to the time criterion model.  相似文献   

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The lay public inherits much of its information about disability and mental illness through the media, which often relies on information from popular scientific works. Autism, as it was defined during the dominance of psychogenic paradigms of mental illness, generated certain tropes surrounding it, many of which have been popularized through media representations. Often inaccurate, these tropes have persisted into contemporary times despite a paradigmatic shift from psychogenic to biological explanations and treatments for mental illness. The current article examines images and articles of children with autism from the 1960s and the early 2000s in major news media and scientific literature to highlight the persistence of themes of fragmentation and the imprisonment of children with autism. While these themes have persisted in psychological and media literature, narratives of people with autism and their families often present a different perspective. This results in two divergent 'realities' of autism being disseminated into the general public.  相似文献   

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Between the 1960s and the 1980s there has been an increase in the Journal of Motor Behavior (JMB) of neuromuscular theories of control, of continuous records showing amplitude or force over time, and of electromyograms (EMGs). Investigations of the advance programming of complex movements have also increased. There has been a decrease in paced manual tracking, in movements along a fixed path, and in studies of proprioception. Investigations of transfer or interference, of motor learning, and of muscular fatigue have also decreased. Some investigators still appear to be unaware of the contraction bias or regression effect.  相似文献   

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