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61.
Joanna Blake Sheilah McConnell Gayle Horton Nancy Benson 《Infant and child development》1992,1(3):127-136
The entire repertoire of communicative gestures was documented in a longitudinal, observational study of 10 infants, whose combined ages covered the range from 9 to 22 months. Early in the second year, giving as a request to do something with the object increased, while emotive gestures decreased. Later in the second year, pointing gestures increased, while protest gestures tended to decrease. Combining gestures with vocalization tended to increase only for protest gestures later in the second year. Eye contact showed a small but continuous increase in coordination with gestures over the second year, particularly with comment, request, and emotive gestures. These findings indicate an increasing use of the parent as an agent and of the informative function in non-verbal communication during this period of transition to verbal communication. 相似文献
62.
Jonathan Grainger J. Kevin O’Regan Arthur M. Jacobs Juan Segui 《Attention, perception & psychophysics》1992,51(1):49-56
Two experiments are described that measured lexical decision latencies and errors to five-letter French words with a single higher frequency orthographic neighbor and control words with no higher frequency neighbors. The higher frequency neighbor differed from the stimulus word by either the second letter (e.g.,astre-autre) or the fourth letter (chope-chose). Neighborhood frequency effects were found to interact with this factor, and significant interference was observed only tochope-type words. The effects of neighborhood frequency were also found to interact with the position of initial fixation in the stimulus word (either the second letter or the fourth letter). Interference was greatly reduced when the initial fixation was on the critical disambiguating letter (i.e., the letterp inchope). Moreover, word recognition was improved when subjects initially fixated the second letter relative to when they initially fixated the fourth letter of a five-letter word, but this second-letter advantage practically disappeared when the stimulus differed from a more frequent word by its fourth letter. The results are interpreted in terms of the interaction between visual and lexical factors in visual word recognition. 相似文献
63.
This paper studies a class of infinite-valued predicate logics. A sufficient condition for axiomatizability of logics from that class is given.To the memory of Jerzy Supecki 相似文献
64.
Microinjections of leupeptin in the frontal cortex or dorsal hippocampus block spatial learning in the rat 总被引:1,自引:0,他引:1
Adult male Long-Evans hooded rats were given bilateral microinjections of 18 mM leupeptin or saline through cannulae implanted with tips aimed at the frontal cortex or CA1 or CA3 hippocampal cell fields. Five minutes following injections animals were allowed to complete an eight-arm radial maze. The acquisition criterion required that the animal make 7 correct choices of the first 8, and 8 correct choices of the first 10, for five consecutive sessions. Leupeptin slowed acquisition of the eight-arm radial maze task when injected into the CA1 and CA3 hippocampal fields or the frontal cortex, but did not influence spontaneous activity. These results suggest that earlier reports of the amnestic effect of leupeptin when administered into the lateral cerebral ventricle may have been due to effects within the cortex and hippocampus. The present experiment represents the first attempt to identify behaviorally those brain areas in which leupeptin acts to alter learning. 相似文献
65.
Context effects in stroop-like word and picture processing 总被引:7,自引:0,他引:7
Presents a series of 6 experiments in which Stroop-like effects were generated by modally pure color-color, picture-picture, and word-word stimuli instead of the usual modally mixed color-word or picture-word stimuli. Naming, reading, and categorization tasks were applied. The Stroop inhibition was preserved with these stimuli but unexpectedly showed a semantic gradient only in the naming and not in the reading task. Word categorizing was slower and more interference prone than picture categorizing. These and other results can be captured by a model with two main assumptions: (a) semantic memory and the lexicon are separate, and (b) words have privileged access to the lexicon, whereas pictures and colors have privileged access to the semantic network. Such a model is developed and put to an initial test. 相似文献
66.
Spatial frequencies and the cerebral hemispheres: contrast sensitivity, visible persistence, and letter classification 总被引:1,自引:0,他引:1
The hypothesis that the two cerebral hemispheres are specialized for processing different visual spatial frequencies was investigated in three experiments. No differences between the left and right visual fields were found for: (1) contrast-sensitivity functions measured binocularly with vertical gratings ranging from 0.5 to 12 cycles per degree (cpd); (2) visible persistence durations for 1- and 10-cpd gratings measured with a stimulus alternation method; and (3) accuracy (d') and reaction times to correctly identify digitally filtered letters as targets (L or H) or nontargets (T or F). One significant difference, however, was found: In Experiment 3, a higher decision criterion (beta) was used when filtered letters were identified in the right visual field than when they were identified in the left. The letters were filtered with annular, 1-octave band-pass filters with center spatial frequencies of 1, 2, 4, 8, and 16 cpd. Combining four center frequencies with three letter sizes (0.5 degrees, 1 degree, and 2 degrees high) made some stimuli equivalent in distal spatial frequency (cycles per object) and some equivalent in proximal spatial frequency (cycles per degree). The effective stimulus in the third experiment seemed to be proximal spatial frequency (cycles per degree) not distal (cycles per object). We conclude that each cerebral hemisphere processes visual spatial frequency information with equal accuracy but that different decision rules are used. 相似文献
67.
Mark D. Rapport Sheila O. Quinn George J. DuPaul Eugene P. Quinn Kevin L. Kelly 《Journal of abnormal child psychology》1989,17(6):669-689
This investigation examined the relationship between methylphenidate (MPH) and the learning and recall of paired associations by children with attention deficit disorder with hyperactivity (ADDH). Forty-five children with ADDH were randomly assigned to one of three groups (novel, partial mastery, and mastery learning) that varied in the amount of previous learning of paired associations and participated in a double-blind, placebo-control, repeated-measures-across-dose (crossover) design. Each child received four doses of MPH (5 mg, 10 mg, 15 mg, and 20 mg) and a placebo in a random, counterbalanced sequence. The results indicated that both the rate of acquisition and accuracy in learning paired associations were significantly, but differentially, affected by MPH dose and the degree of learning mastery. The implications of these results for psychopharmacological research and the monitoring of psychostimulant effects on children's learning performance in academic settings are discussed.The authors wish to acknowledge and express their sincere appreciation to the graduate and undergraduate student members of the Children's Learning Clinic. 相似文献
68.
Semantic priming in a lexical decision task was investigated with concurrent pretarget and posttarget primes. The posttarget prime also served as a pattern mask of the lexical decision target. Forward priming is defined as the presence of a semantically related pretarget prime and an unrelated posttarget prime. Backward priming is defined as the presence of a semantically related posttarget prime and an unrelated pretarget prime. Forward and backward priming were compared both when the nonword foils were "legal" and when they were "illegal" with respect to English orthography. Predictions were derived for two general approaches to word recognition: spreading-activation and expectancy-set theories. Both approaches assume that word representations occupy distinct, nonoverlapping locations in memory. Backward-prime facilitation was equivalent to forward-prime facilitation when nonword foils were illegal; however, backward-prime facilitation was not significant when nonword foils were legal. These results challenge both approaches. The proposed solution uses semantic-space (distributed) representations that are functionally unitized by a resonant matching (verification) process. 相似文献
69.
Gail F. Brenner Nancy K. Norvell Marian Limacher 《American journal of community psychology》1989,17(6):831-836
Assessed the number of sources of supportive and problematic social interactions in the total social network as well as the number who were the sources of consistently supportive or problematic interactions in a sample of 2nd year medical students. Number of problematic interaction sources was hypothesized to be more predictive of psychological and physical well-being than number of supportive interaction sources. Results showed that total supportive and total problematic interaction sources were equally predictive of life satisfaction. The presence of at least one individual who is a consistent source of problematic interactions was most predictive of lower life satisfaction. Results indicate the importance of studying both supportive and problematic social interactions. They also suggest that interactions with individuals that are consistently problematic may negatively impact upon well-being. 相似文献
70.
Bengt O. Muthén 《Psychometrika》1989,54(3):385-396
The problem of detecting instructional sensitivity (item basis) in test items is considered. An illustration is given which shows that for tests with many biased items, traditional item bias detection schemes give a very poor assessment of bias. A new method is proposed instead. This method extends item response theory (IRT) by including item-specific auxiliary measurement information related to opportunity-to-learn. Item-specific variation in measurement relations across students with varying opportunity-to-learn is allowed for.This paper was presented at the 1987 AERA meeting in Washington, DC. This research was supported by grant OERI-G-86-003 from the Office of Educational Research and Improvement, Department of Education. The author thanks Michael Hollis and Chih-fen Kao for valuable research assistance, and appreciates valuable comments made by an anonymous reviewer. 相似文献