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961.
Dr. Andrew N. Rowan 《Science and engineering ethics》1995,1(2):181-184
Conclusion The past one hundred fifty years of debate over the use of animals in research and testing has been characterized mainly byad hominem attacks and on uncritical rejection of the other sides’ arguments. In the classroom, it is important to avoid repeating exercises
in public relations and to demand sound scholarship.
This paper is a modification of material originally included in the handbook which accompanied the American Association for
the Advancement of Science (AAAS) Seminar “Teaching Ethics in Science and Engineering”, 10–11 February 1993. 相似文献
962.
Gibson (1966, 1979) suggested that an important property of perception is that the observer is active. Two experiments were conducted to examine the benefits of active observation in determining dynamic spatial orientation. Subjects were presented with displays simulating locomotion through a three-dimensional environment. Active observers continuously controlled locomotion, whereas passive observers viewed the display. During the trial, the display was blacked out for a brief period, followed by a static image that was at either the correct or the incorrect orientation following the blackout. Subjects were required to indicate whether they were positioned at the correct extrapolated orientation. The presence or absence of orientation change, the type of change (changes in rotation about the depth axis [roll], horizontal axis [pitch], or forward translation), the duration of the blackout, and the consistency of change were varied. In addition, the experiments used either a compensatory or a pursuit tracking task. Active observers had greater sensitivity than did passive observers in detecting a change for both tracking tasks. Subjects in both experiments exhibited greater sensitivity in detecting inconsistent changes (relative to consistent changes), suggesting that the dynamics specified by optical flow were incorporated in extrapolated orientation. In addition, sensitivity decreased with an increase in blackout duration. The results are discussed in terms of an extrapolation model of perception that incorporates the responses executed by active observers. 相似文献
963.
Hendrik N. J. Schifferstein 《Attention, perception & psychophysics》1995,57(1):56-70
Manipulating stimulus spacing, stimulus frequency, or stimulus range usually affects intensity judgments. In six experiments, I investigated the locus of analogues of these contextual effects in a “difference” estimation task. When all stimuli elicited the same taste quality, stimulus distribution affected the scale values only when water was included in the stimulus set (Experiments 1–3). When the subjective ranges of two taste qualities were manipulated, different scale values were obtained for the separate qualities in the two conditions (Experiment 4). Manipulation of the expected response distribution did not affect the scale values or the responses (Experiments 5–6). It is concluded that shifts in stimulus distributions or stimulus ranges result in shifts in subjective scale values. The contextual effects can be interpreted as relative shifts of a number of gustatory continua, with water lying on a separate continuum. Proposed is a model for context-dependent judgments, consisting of four stages: stimulus classification, stimulus placement, continuum placement, and continuum projection. 相似文献
964.
Richard A. Tyrrell Ph.D. Julian F. Thayer Bruce H. Friedman Herschel W. Leibowitz Ellie L. Francis 《Integrative psychological & behavioral science》1995,30(1):46-67
Although the eyes and the heart serve very different purposes, each receives autonomic innervation. Capitalizing on recent
theoretical and technological innovations in the understanding and assessment of oculomotor and cardiovascular behavior, three
experiments measured behavioral covariation between the oculomotor and cardiovascular systems. Measures of dark focus and
dark vergence indexed oculomotor tone, and the spectral decomposition of variations in heart rate indexed cardiovascular control
mechanisms. In Experiment 1, individual differences in cardiovascular parameters could predict individuals’ dark vergence
(R2=.806) but not their dark focus (R2=.404). In Experiment 2, the same parameters were measured from subjects who experience either panic attacks (n=11) or blood phobia (n=9). Heart rate was positively correlated with dark vergence and the two subject groups were separable based on both oculomotor
and cardiovascular variables. Using a within-subjects approach, Experiment 3 found that both dark vergence and dark focus
tended to be nearer during sympathetic dominance of the heart than during parasympathetic dominance, within-subjects variations
in cardiovascular parameters could predict dark focus, and between-subjects variations in interbeat intervals could predict
dark vergence. Shared patterns of autonomic activation may be responsible for this eye-heart link. 相似文献
965.
Mark A. Lumley Willfried Schramm Cynthia S. Pomerleau Ovide F. Pomerleau Richard H. Smith 《Behavior research methods》1995,27(4):470-475
Cortisol can be used to indicate stress level as well as to monitor certain disease states. Although cortisol can be sampled from blood and urine, saliva sampling has decided advantages. Unfortunately, whole saliva contains a number of substances that can metabolize or bind with cortisol, potentially confounding analysis and quantitation. We introduce a semipermeable pouch that accumulates a contaminant-free salivary ultrafiltrate, thereby overcoming a number of the problems encountered with whole saliva. In three studies, we demonstrate accuracy and utility of the device for cortisol determination: (1) in an artificial medium, 60%–77% of the cortisol was recovered in the ultrafiltrate; (2) in vivo, ultrafiltrate cortisol correlated highly with whole-saliva cortisol collected under ideal conditions; and (3) ultrafiltrate cortisol evinced positive relationships with depression and cigarette use, consistent with studies in the literature. We conclude that this device and saliva-filtering technologies in general are useful in applications requiring quantitation of cortisol. 相似文献
966.
Louann Gerken Walter D. Murphy Richard N. Aslin 《Attention, perception & psychophysics》1995,57(4):475-486
Although infants have the ability to discriminate a variety of speech contrasts, young children cannot always use this ability in the service of spoken-word recognition. The research reported here asked whether the reason young children sometimes fail to discriminate minimal word pairs is that they are less efficient at word recognition than adults, or whether it is that they employ different lexical representations. In particular, the research evaluated the proposal that young children’s lexical representations are more “holistic” than those of adults, and are based on overall acoustic-phonetic properties, as opposed to phonetic segments. Three- and four-year-olds were exposed initially to an invariant target word and were subsequently asked to determine whether a series of auditory stimuli matched or did not match the target. The critical test stimuli were nonwords that varied in their degree of phonetic featural overlap with the target, as well as in terms of the position(s) within the stimuli at which they differed from the target, and whether they differed from the target on one or two segments. Data from four experiments demonstrated that the frequency with which children mistook a nonword stimulus for the target was influenced by extent of featural overlap, but not by word position. The data also showed that, contrary to the predictions of the holistic hypothesis, stimuli differing from the target by two features on a single segment were confused with the target more often than were stimuli differing by a single feature on each of two segments. This finding suggests that children use both phonetic features and segments in accessing their mental lexicons, and that they are therefore much more similar to adults than is suggested by the holistic hypothesis. 相似文献
967.
John B. Jolly Psy.D. Jeffrey N. Wherry David C. Wiesner Douglas H. Reed J. Chris Rule Janet M. Jolly 《Journal of abnormal child psychology》1994,22(6):691-702
This study examined the mediating role of anxiety in the self-reports of somatic complaints in 96 depressed adolescent inpatients. Sixty-four subjects with major depressive episodes and comorbid anxiety disorders (MDE-A) determined from the Diagnostic Interview for Children and Adolescents-Revised (DICA-R) reported significantly more somatic complaints than 32 adolescents having major depressive episodes without comorbid anxiety (MDE). An analysis of covariance demonstrated that, with anxiety symptoms controlled, MDE and MDE-A groups did not differ significantly in somatic complaints. A hierarchical multiple-regression analysis revealed that, with demographic and anxiety symptoms controlled, depressive symptoms did not contribute to the explanation or prediction of somatic complaints. The results suggest that anxious, but not depressive symptoms, are independently associated with somatic complaints. The results are discussed in light of new affective models of psychopathology. 相似文献
968.
Dr. Heino F. L. Meyer-Bahlburg David E. Sandberg Curtis L. Dolezal Thomas J. Yager 《Journal of abnormal child psychology》1994,22(6):643-660
Parent-report based scales for the assessment of sex-dimorphic behavior are an important tool in research on psychosexual differentiation and its disorders. This paper presents the factor analysis and corresponding scale development for the slightly expanded Child Game Participation Questionnaire (Bates & Bentler, 1973), based on the parents of a demographically diverse school sample of 355 girls and 333 boys aged 6 to 10 years. Evidence supporting each of three theoretical positions in gender assessment — unidimensional bipolar, two-dimensional unipolar, and multidimensional — was provided. Effect sizes were unusually large for gender, but small for age, socioeconomic level, and race/ethnicity.This research was supported in part by a NICHD postdoctoral fellowship (NRSA HD06726; sponsor: Dr. Meyer-Bahlburg) awarded to Dr. Sandberg, by grants to Dr. Ehrhardt and Dr. Meyer-Bahlburg from the Spencer Foundation, the William T. Grant Foundation, the Ford Foundation, and NIMH (center grant 2-P50-MH43520, Anke A. Ehrhardt, Ph.D., Principal Investigator), and by the NIMH Clinical Research Center grant MH-30906.We thank the children and parents who participated in the study. Dr. Jacob Cohen consulted on statistical matters. Ms. Patricia Connolly provided word processing services. A portion of this work was presented as a poster at the XIth Biennial Meeting of the International Society for the Study of Behavioral Development, Minneapolis, Minnesota, July 3–7, 1991 (Abstracts, p. 285). 相似文献
969.
Robert F. Belli D. Stephen Lindsay Maria S. Gales Thomas T. McCarthy 《Memory & cognition》1994,22(1):40-54
The four experiments reported here provide evidence that (1) misleading postevent suggestions can impair memory for details in a witnessed event and (2) subjects sometimes remember sug-gested details as things seen in the event itself. All four experiments used recall tests in which subjects were warned of the possibility that the postevent information included misleading sug-gestions and were instructed to report both what they witnessed in the event and what was men-tioned in the postevent narrative. Recall of event details was poorer on misled items than on control items, and subjects sometimes misidentified the sources of their recollections. Our re-sults suggest that these findings are not due to guessing or response biases, but rather reflect genuine memory impairment and source monitoring confusions. 相似文献
970.
Subjects can name color words faster than they can name color patches. To account for that effect, a generic model of naming is described which assumes that words access the mental lexicon directly, whereas color patches do so only indirectly via an initial imaginal or semantic representation. However, Lund (1927) reported that the naming advantage for words disappeared when all the items to be named on a page were the same (i.e., they were blocked). In the present study, three experiments are reported that were designed to provide a clearer empirical definition of Lund’s blocking effect and to ascertain the extent to which it requires a modification of the generic model. The blocked lists had 50 items arranged into 10 blocks, with each block homogeneous with respect to color. The block lengths were either all a predictable length of 5 items or they varied randomly from 1 to 9 items. The data indicated the following: (1) The blocking effect occurred even when the task required a full identification of each item, and (2) the blocking effect was confined to within-block transitions. Blocking seemed to eliminate the word advantage by allowing the subject to re-use the lexical entry used for the immediately prior item, which is consistent with the generic model. 相似文献