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81.
82.
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   
83.
Random dots moving with various velocity gradients were presented to observers; the motion was yoked to head movement in one condition and to no head movement in another. In Experiment 1, 12 observers were shown motion gradients with sine, triangle, sawtooth, and square waveforms with amplitudes (equivalent disparities) of 12′ and 1° 53′. In Experiment 2, 48 observers were shown only the sinewave or square-wave gradient of 1° 53′ disparity either with or without head movement so that the observers’ expectation to see depth in one condition did not transfer to another. The main findings were: (1) with 12′ disparity, the head-movement condition produced perceived depth but almost no perceived motion, whereas the no-head-movement condition produced both perceived depth and perceived motion; (2) with 1° 53′ disparity, both conditions produced perceived depth and perceived motion; and (3) when the expectation to see depth was removed, the no-head-movement condition with the square-wave gradient produced no perceived depth, only motion. We suggest that monocular stereopsis with head movement can be achieved without perception of motion but monocular stereopsis without head movement requires perception of motion.  相似文献   
84.
OPTIMISM AND FUNDAMENTALISM   总被引:2,自引:0,他引:2  
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85.
Considerable evidence has accumulated in support of the hypothesis that subclinical depression may inhibit role performance in important ways. However, interpersonal stress and marital discord often precede the development of depressive symptomatology and may independently predict deficits in family role functioning. In addition, cognitive theories suggest that persons with subclinical depression may report poor role functioning even in the absence of any real performance deficits. The current research examines the possibility (1) that the effect of depression on the fulfillment of important family roles is attributable to previously unmeasured contextual variables of ongoing interpersonal stress and/or relationship dissatisfaction or, alternatively, (2) that this relationship is the result of depressive distortion associated with self-report of symptoms and performance. Multiple regression analyses of interview data collected from 495 community-dwelling adults found, however, that depression is related to role functioning beyond any spurious effects attributable to interpersonal stress, spousal stress, or marital satisfaction. In addition, the effect of depression persists when collateral reports of role functioning utilized. Accordingly, it appears that subclinical depression is related to decrements in role performance, and this effect is not entirely due to contextual elements or shared method variance between self-report measures.The authors acknowledge research support from Research Grants R01-AA-07250 and R01-AA-07218 from the National Institute on Alcohol Abuse and Alcoholism, Research Grant R01-DA-07417 from the National Institute on Drug Abuse, and National Institutes of Mental Health Grant A-41487-07.  相似文献   
86.
The present study compared the ability of novice divers to apply decompression tables having learnt how to use them in either the same or a different environment. Those subjects who had learnt how to use the tables in a different environment (i. e. had learnt on dry land and were tested underwater or vice-versa) performed on average 64 percent worse than those who had the same environment for both learning and test. This effect could not be ascribed to the disruption brought about by changing environments. The results show that contextual effects on memory extend beyond the recall of word lists (Godden and Baddeley, 1975) to the ability to implement potentially important instructions.  相似文献   
87.
This study explores Black teachers' preferences for and ratings of consultant effectiveness as a function of consultant race, consultant style, and teacher stage of racial identity development. No significant differences were noted in preferences for either a same- or opposite-race consultant. Participants preferred and rated as more effective an instrumentally oriented consultant.  相似文献   
88.
The present study was designed to investigate visually handicapped students' explanations for failure when the motive to maintain or enhance self-esteem was in conflict with the motive to present a favorable social image. Subjects experienced manipulated failure in a text comprehension task and were subsequently asked to give causal and responsibility attributions in the presence of either a visually handicapped or a non-handicapped experimenter. It was expected that visually disabled participants would claim a handicap-bonus from the non-handicapped experimenter by explicitly presenting non-defensive attributions and accounts as well as handicap-related responses, while defensive explanations should be more pronounced when faced with a blind experimenter. The data provide support for the existence of presumed social expectations as determinants of individuals' verbal self-presentations.  相似文献   
89.
We examined the effects of a self-monitoring program on reducing the frequency of negative statements of a student with mild mental retardation who was enrolled in a self-contained classroom at a middle school. A changing criterion design was used within a multiple baseline design across two classroom periods. Additionally, the frequency of positive statements was reported. The results showed a decrease in the number of negative statements, and an increase in the number of positive statements. Maintenance data collected up to 8 weeks after the program ended indicated that the student continued to emit positive rather than negative statements. The use of this procedure to decelerate undesirable behavior is discussed.  相似文献   
90.
To determine the frequency and correlates of nonsuicidal physically self-damaging acts in 12–14 year olds, a two stage epidemiologic survey with a self-administered questionnaire (N=3283) followed by a psychiatric interview of a subsample of the adolescents and their parents (N=444) was used. Prevalence estimates of interview validated nonsuicidal physically self-damaging acts were 2.46% in males and 2.79% in females. Significant relationships were found between nonsuicidal physically self-damaging acts and suicidal ideation, major depression and undesirable life events. Data suggest that physically self-damaging acts occur at substantial rates during early adolescence. The strong correlation between nonsuicidal self-destructive acts and both suicidal ideation and major depression clarifies prior conflicting reports in the literature and suggests that a history of self-damaging acts should be taken into consideration when evaluating for possible depression and suicide risk.  相似文献   
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