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951.
P. A. S. Breslin G. K. Beauchamp E. N. Pugh 《Attention, perception & psychophysics》1996,58(3):327-341
We investigated the ability of subjects to discriminate sugars with a whole-mouth forced-choice paradigm, in which a standard solution was compared with a test solution of varied concentration. Discrimination probabilities were U-shaped functions of test concentration: for 6 subjects and pairwise combinations of fructose, glucose, and sucrose, discriminability always declined to chance over a narrow range of test concentrations. At concentrations ≦ 100 mM, maltose was indiscriminable from fructose but discriminable at higher concentrations for 4 subjects. By analogy with themonochromacy of night vision, whereby any two lights are indiscriminable when their relative intensities are suitably adjusted, we call the gustatory indiscriminability of these sugarsmonogeusia. The simplest account of monogeusia is that all information about the indiscriminable sugars is represented by a single neural signal that varies only in magnitude. The discriminability of maltose from the other sugars at higher concentrations is consistent with the hypothesis that maltose also activates a second gustatory code. 相似文献
952.
Fetal brain tissue from the occipital or the frontal cortex was implanted into the damaged occipital cortex of adult rats. The animals receiving grafts of embryonic frontal cortex showed partial restoration of brightness discrimination while recipients given homologous implants of occipital cortex were as impaired as those animals with lesions alone. Neither frontal nor occipital grafts aided in the performance of a pattern discrimination problem; both groups of brain-damaged animals were unable to learn the task. Nonetheless, both groups of animals had viable and enlarged grafts with similar neuronal and glial profiles. 相似文献
953.
This study was designed to provide a detailed analysis of the parameters which interact to produce a field hockey drive. The drive was performed by an elite performer under two conditions of uncertainty (Blocked and Random). The subject was asked to drive a field hockey ball toward a specified target. In the Blocked condition the speed of the approaching ball remained constant (20, 30 and 40 m.p.h.) while in the Random condition these speeds were randomly assigned to each trial. Cine analysis of the subject's successful responses under the two experimental conditions led to an investigation of the kinematics, phasing, and timing of the stroke. The subject placed emphasis upon varying the initial phases of the stroke (i.e., backswing and preparatory phases) in order to produce a temporally consistent ballistic downswing to ball contact. It seemed likely that the subject appraised the ball speed that was being delivered and then incorporated additional stick movement to ‘mark time’ before initiating temporally consistent movement phases, as spatial uncertainty increased, the subject delayed her response initiation, but then tended to respond in intervals of one reaction time for each stroke phase. Consistency was evident for displacement and initiation point values, but to a lesser extent than existed for the other variables. However, as a result of this adjustment in spatial location and displacement of the stick end during the preliminary phases of the response, the subject was able to produce a consistent and accurate ballistic downswing. 相似文献
954.
955.
Although vocational psychologists and sociologists have a long history of researching occupational choice, their theoretical postures have almost always been shaped in light of information on males, with little consideration for females. This article is an addition to others which attempt to correct this shortcoming in the literature. The article reviews the dominant conceptual schemes used to study occupational choice, considers potentially female-specific variables, and provides a typology for the analysis of women's marital-familial statuses and work modes. 相似文献
956.
957.
958.
The question of whether or not lexical information is accessed directly from a visual code or by a process of phonetic mediation was investigated in three lexical decision experiments. Phonetic similarity influenced decisions about visually presented words only when they were to be discriminated from orthographically regular nonwords. When consonant strings or random letter strings were used as nonwords, phonetic similarity effects were absent, and graphemic similarity exerted a powerful effect while evidence of semantic priming was found. This pattern was interpreted as evidence of direct lexical access, which is probably the normal processing mode for skilled readers. Phonetic coding, when it occurs, may be a storage strategy rather than a part of the addressing chain for lexical structures. 相似文献
959.
Two experiments were carried out in order to try to resolve the controversy about whether the semantic processing of a word necessarily involves all the elements of its meaning. In the first experiment, subjects categorized a list of auditorially presented words according to whether or not they were natural consumable solids (e.g., “apple“). They were then given an unexpected test of their ability to recall the whole list, which contained equal numbers of words with none, one, two, or all three of the target components. The results confirmed the prediction that the greater the number of components a word has in common with a target category, the better it will be recalled. The second experiment used a visual presentation of a list of words, which subjects scanned for members of a particular target category. There were four different target categories assigned to independent groups of subjects. The results again confirmed the prediction. On the assumption that memorability in such tasks is determined by amount of processing, we conclude that some elements of the meaning of a word can be processed without having to process all of them. 相似文献
960.
Elliot G. Mishler 《Journal of psycholinguistic research》1978,7(4):279-305
Natural conversations in first-grade classrooms are analyzed. Exchanges that are initiated and extended by questioning are the focus of attention, and analyses are directed principally to a comparison of adult-initiated and child-initiated interrogative series. Differences in structural features are found for each component utterance of an interrogative unit of discourse, namely, question, response, and confirmation. Adults ask more constraining questions than children, and children respond in more complex although less appropriate ways to children's questions than to adults' questions. The type of discourse within which an utterance is located influences the features of children's responses to children's but not to adults' questions. These differences are interpreted as reflecting differences in the relative power of adults and children in these settings.This work has been supported by a grant from the National Science Foundation for research on Social Effects on Language and Communication, Grant No. GS-3001. 相似文献