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991.
992.
Amir?AshkenaziEmail author Michael?Fritz John?Buckley Lawrence?E.?Marks 《Behavior research methods》2004,36(1):83-88
We describe a new, open flow device for presenting taste stimuli to human subjects under controlled conditions of timing. The device delivers each stimulus as a mist to the participant’s tongue through one of 16 nozzles attached to a linear slide. Software controls the position of the slide, the duration of the stimulus, and the duration of the pre- and poststimulus water rinses and records the responses of the participant. Temporal characteristics of this system make it especially applicable to studies on the role of attention in taste perception. 相似文献
993.
Justification for public funding of academic research is based on the linear model of technological advance first proposed by Francis Bacon. The model hypothesizes that government subsidized science generates new technology which creates new wealth. Mainstream economics supports Bacons model by arguing that academic research is a public good. The Bayh–Dole Act allows universities to privatize federally funded research and development (R&D) which is in direct conflict with the public good argument. Diminishing returns to university R&D, challenges to Bacons linear model and the labor exploitation of young scientists by research universities suggest that policy makers may want to reconsider the system for allocating federal R&D to universities and colleges. 相似文献
994.
David?A.?WashburnEmail author Michael?J.?Rulon Jonathan?P.?Gulledge 《Behavior research methods》2004,36(2):173-179
Many exciting findings have been reported in the 15 years since monkeys were first demonstrated to have the capacity to perform
computerized tasks. The present data indicate that albino rats can also learn to respond to computer-generated stimuli by
manipulating a joystick. Although the rat’s control of the cursor is not as skillful as has been reported for primate species,
it is clearly better than chance and suggests the great potential for comparative investigation afforded by use of the computer
test system. 相似文献
995.
Beatrice?M.?de?OcaEmail author Michael?S.?Fanselow 《Integrative psychological & behavioral science》2004,39(4):318-333
Defensive responses to a cat were observed in rats given excitotoxic lesions of the central nucleus of the amygdala (ACe),
dorsolateral periaqueductal gray (dlPAG), ventral periaqueductal gray (vPAG), or sham lesions. Rats were placed adjacent to
a compartment containing a cat. Sham-lesioned rats avoided the area nearest the cat and preferred the area furthest away from
the cat. They also exhibited numerous defensive responses including, climbing, escape from the apparatus, and freezing. Rats
with lesions of the ACe reacted like the sham lesioned rats by preferring the area of the apparatus furthest from the cat,
however they climbed and escaped significantly less than sham lesioned rats. Avoidance of the area adjacent to the cat was
attenuated in rats with lesions of the vPAG. Climbing along the walls of the apparatus was also attenuated in rats with lesions
of the vPAG. Escapes from the apparatus were not significantly reduced by lesions of the vPAG and dlPAG. Thus, ACe lesions
attenuated climbing and eliminated escapes, but did not impair locomotion of the rat away from the cat. 相似文献
996.
The aim of the study was to examine the relationship between body esteem and body fat in British school children. Two hundred and seventy seven, 11–14-year-old children from central England took part in the study. Body esteem was measured using the Body Esteem Scale for children and percent body fat was determined by skin-fold measures. Results indicate that body esteem and adiposity were negatively related for the whole sample, for boys and girls and for White children, Black children and Asian children. Factorial ANOVA also indicated differences in body esteem according to gender and ethnicity. Boys and Black children had significantly higher body esteem than girls and Asian children respectively. Differences in body fat were also evident according to gender with boys being leaner than girls. No differences in body esteem or body fat were evident across school years. 相似文献
997.
Hypothesis generation,probability judgment,and individual differences in working memory capacity 总被引:4,自引:0,他引:4
This research examined the role of working memory (WM) in probability judgment and hypothesis generation using a simulated task that involved estimating the likelihood that particular menu items would be ordered by customers at a dinner. Five main findings were observed. First, judgments of the likelihood of individual items were made relative to alternatives retrieved from long-term memory. Second, the number of alternatives retrieved was positively correlated with a measure of WM-capacity (the operation-span task). Third, participants' probability judgments were subadditive (summing to well over 100%). Fourth, the degree to which participants' judgments were subadditive was affected by the number and strength of the alternatives retrieved from long-term memory. Fifth, the degree to which participants were subadditive was negatively correlated with WM-capacity. The results suggest that individual differences in WM-capacity are fundamental to hypothesis generation and probability judgment. 相似文献
998.
Symmetry properties have been shown to determine the perceived complexity of certain patterns. We used a paired-comparison method to obtain judgments of relative complexity for a family of two-dimensional regular patterns called band patterns. Although the complexity of these patterns is well predicted by their symmetry properties we were unable to explain an interaction observed between two of these properties for our experimental patterns. We discuss the implications of our results for two predominant approaches to the perceived complexity of patterns. Neither approach takes into account that the presence of grouping sometimes makes it difficult to perceive a relationship within the pattern that would--were it not for the grouping--simplify it. We conclude that grouping can mask simplicity and that this phenomenon is crucial to the understanding of perceived complexity. 相似文献
999.
Otto MW Hinton D Korbly NB Chea A Ba P Gershuny BS Pollack MH 《Behaviour research and therapy》2003,41(11):1271-1276
Cambodian refugees with posttraumatic stress disorder (PTSD) represent a cohort in severe need of treatment, but little information is available to guide treatment choices. We selected a sample of pharmacotherapy-refractory individuals to test the efficacy of combination treatment with sertraline and cognitive-behavior therapy (CBT) for treating PTSD. Participants in this pilot study were ten Khmer-speaking women who had been at a mean age of 22-26 years during the Pol Pot period (1975-1979). These patients were randomly assigned to either sertraline alone or combined treatment. We found that combined treatment offered additional benefit in the range of medium to large effect sizes for PTSD and associated symptoms. Our findings indicate that substantial gains can be achieved by adding CBT to pharmacotherapy for PTSD, and that a program of CBT emphasizing information, exposure, and cognitive-restructuring can be successfully modified for Khmer-speaking refugees. 相似文献
1000.
Rentz TO Powers MB Smits JA Cougle JR Telch MJ 《Behaviour research and therapy》2003,41(11):1337-1353
The aims of this study were to investigate exposure-based treatments for cynophobia (dog phobia) and to test a newly developed hybrid imaginal exposure treatment that we have named active imaginal exposure. The treatment introduces an in vivo coping component to imaginal exposure whereby the patient physically performs coping responses to an imagined feared stimulus. Eighty-two participants meeting DSM-IV criteria for specific phobia (animal subtype) were randomly assigned to one of three 30-min. treatments: (a) active-imaginal exposure (AI), (b) imaginal exposure alone (IE), or (c) graduated in vivo exposure (IV). Participants completed a behavioral approach test at pre, post, and four-week follow-up. Significant pre- to posttreatment improvement was observed in all three treatment conditions. Response rates at posttreatment were 51.9, 62.1, and 73.1% for the IE, AI, and IV groups respectively. Likewise, effect sizes at posttreatment were 0.76, 1.41, and 1.55 for the IE, AI, and IV groups respectively. Although in the predicted direction, the between group differences were not significant. A similar pattern of results was observed at follow-up. Further, safety behavior utilization during treatment was associated with less improvement--particularly in the two imaginal treatment conditions. Exposure treatments of dog phobia appear feasible and effective in reducing phobic fear and avoidance associated with dog phobia. Furthermore, preliminary evidence suggests that our active-imaginal exposure treatment may be a viable alternative to in vivo exposure. 相似文献