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971.
972.
In this paper, we describe software that turns a Macintosh computer into an off-the-shelf tool for experiments on visual search. Our design goals included portability (between members of the Macintosh computer family and between various research settings), user-friendliness (equivalent to Macintosh programming standards), flexibility (to allow replication and extension of important experiments on visual search), and adaptability (very short design-to-data and data-to-analysis turnaround times). We describe how the software meets these goals in three major phases of an experiment: stimulus construction, experimental control, and statistical analysis. We then list several landmark studies of visual search that can be easily designed and extended with the software. Finally, we outline plans for expanding the experimental variations that will be supported in future versions of the software. 相似文献
973.
Carol A. Fowler Catherine T. Best Gerald W. Mcroberts 《Attention, perception & psychophysics》1990,48(6):559-570
Phonetic segments are coarticulated in speech. Accordingly, the articulatory and acoustic properties of the speech signal during the time frame traditionally identified with a given phoneme are highly context-sensitive. For example, due to carryover coarticulation, the front tongue-tip position for HI results in more fronted tongue-body contact for a /g/ preceded by /l/ than for a /g/ preceded by /r/. Perception by mature listeners shows a complementary sensitivity—when a synthetic /da/-/ga/ continuum is preceded by either /al/ or /ar/, adults hear more /g/s following HI rather than Irl. That is, some of the fronting information in the temporal domain of the stop is perceptually attributed to /l/ (Mann, 1980). We replicated this finding and extended it to a signaldetection test of discrimination with adults, using triads of disyllables. Three equidistant items from a /da/-/ga/ continuum were used preceded by /al/ and /ar/. In the identification test, adults had identified item ga5 as “ga”, and dal as “da”, following both /al/ and /ar/, whereas they identified the crucial item d/ga3 predominantly as “ga” after /al/ but as “da” after /ar/. In the discrimination test, they discriminated d/ga3 from dal preceded by /al/ but not /ar/; compatibly, they discriminated d/ga3 readily from ga5 preceded by /ar/ but poorly preceded by /al/. We obtained similar results with 4-month-old infants. Following habituation to either ald/ga3 or ard/ga3, infants heard either the corresponding ga5 or dal disyllable. As predicted, the infants discrimi-nated d/ga3 from dal following /al/ but not /ar/; conversely, they discriminated d/ga3 from ga5 following /ar/ but not /al/. The results suggest that prelinguistic infants disentangle consonant-consonant coarticulatory influences in speech in an adult-like fashion. 相似文献
974.
Thomas G. Fikes Roberta L. Klatzky James Pellegrino Chick Hebert Larry Murdoch 《Behavior research methods》1990,22(3):290-296
In this paper, we describe an apparatus for measuring reaction times and movement times involved in reaching for real objects. Subjects view an object through a liquid crystal window, which serves as a shutter that can be made clear or opaque quickly (10 msec from opaque to clear, 30 msec from clear to opaque). The subject’s hand rests on a microswitch-equipped home key, and the object sits on a force-sensitive platform so that initiation of reach and time of contact with the object can be marked accurately. The apparatus interfaces with an IBM PC/AT through a digital I/O parallel port, so that reaction times and movement times are recorded automatically. 相似文献
975.
Abstract— Subjects' judgments of the mean of 12 scores were influenced by the way in which the scores were dichotomized. The estimated mean was higher when the three highest scores formed one group (e.g., payments for women) and the nine lowest formed the other (e.g., payments for men) than when the nine highest were one group and the three lowest the other. We call this phenomenon the Will Rogers Illusion (WRI). The WRI occurred only when estimates of the subgroup means were made prior to the estimates of the mean of the whole group. When the latter mean was judged first, the WRI was reversed. These and other data indicate that the means of subgroups can influence judgments of group means, a finding that is relevant to research on social stereotypes. 相似文献
976.
Increases in self-attention as a function of decreases in the relative size of one’s subgroup in a heterogeneous group context
have been shown to result in increased regulation of behavior toward social (normative) standards for behavior. The present
study demonstrated increased regulation of behavior toward a personal standard for behavior as a function of variations in
group composition. One hundred twenty-five subjects individually completed the Creativity subscale of Scott’s Personal Value
Scale assessing attitudes toward originality. They then completed a word-association task in groups ranging in size from 2
to 8. Originality of word-associations was determined by reference to previously established word-association norms and norms
based on frequency of responses given in the present study. Results indicate that originality in responses increase as the
relative size of one’s own subgroup decreases (indexing increases in self-attention) for subjects who value originality. Discussion
centers on the distinction between experimentally manipulated public and private self-attention and standards that are adopted
for behavioral self-regulation.
Portions of this study were presented at the annual meeting of the Eastern Psychological Association, New York, April 1991. 相似文献
977.
This study investigated the psychological and physical health status of 265 crew members on two U.S. Navy ships (a guided
missile cruiser and a frigate on convoy escort duty for tankers under U.S. flag) during the Persian Gulf conflict at four
time periods during combat-ready operations on a single day. Findings suggest that adaptation occurs to extreme stressors
associated with sustained operations. Suggestions are made relative to measures that may minimize psychological and physical
conditions that adversely affect performance under conditions of heavy stress.
Report No. 89-18, supported by the Naval Medical Research and Development Command, Bethesda MD, Department of the Navy, under
research Work Unit No. 63206N.M0096. The opinions expressed in this paper are those of the author and do not reflect the official
policy or position of the Department of the Navy, Department of Defense, nor the U.S. Government. 相似文献
978.
Frederick G. Lopez Christopher W. Thurman 《Journal of counseling and development : JCD》1993,71(5):524-527
In this study the authors investigated differences in the family environments of high- and low-trait angry college students. High-trait angry students described their family environments as significantly less cohesive, less emotionally expressive, more conflictual, and more disorganized than did their low-trait angry counterparts. Implications of the findings to the counseling of students with anger-related problems are discussed. 相似文献
979.
Leo T. Rosenberg 《The Journal of medical humanities》1993,14(1):5-14
Briefly stated my point is that the well-being of each person in a community conceived abstractly may be all too easily sacrificed for the sake of the abstraction. Physicians may offer critically ill patients places in programs of experimental treatment, but there is commonly a catch to the offer. To take part in a program of clinical experiment a patient must not only risk a possible failure of a fresh drug and the chance of destructive side effects from the drug, but the patients must risk only getting the traditional treatment along with a placebo rather than the experimental drug. Placebo control, double blind critical protocols for testing effects of fresh drugs on critically ill patients are a commonplace. I question the scientific objectivity of the protocols and the underlying ethic, and suggest use of alternate protocols. Experimental tests in the treatment gram-negative bacteria blood infections, muscular dystrophy, and AIDS and AIDS-related diseases are examples. 相似文献
980.