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931.
This study evaluates a measurement model for Attention Deficit/Hyperactivity Disorder (ADHD). The DSM-IV divides 18 symptoms into two groups, inattentive and hyperactive/impulsive. Elementary school teachers rated 21,161 children in 4 locations: Spain, Germany, urban US, and suburban US. Confirmatory factor analysis suggested that the 2-factor model (inattention, hyperactivity/impulsivity) shows the best fit. A third factor, impulsivity, was too slight to stand-alone. Children with academic performance problems were distinguished by inattention, but children with behavior problems typically had elevations in inattention, hyperactivity, and impulsivity. Between-site differences were statistically significant, but so small that we conclude that same measurement model fits all 4 samples in 2 continents.  相似文献   
932.
Does age constrain the outcome of all language acquisition equally regardless of whether the language is a first or second one? To test this hypothesis, the English grammatical abilities of deaf and hearing adults who either did or did not have linguistic experience (spoken or signed) during early childhood were investigated with two tasks, timed grammatical judgement and untimed sentence to picture matching. Findings showed that adults who acquired a language in early life performed at near-native levels on a second language regardless of whether they were hearing or deaf or whether the early language was spoken or signed. By contrast, deaf adults who experienced little or no accessible language in early life performed poorly. These results indicate that the onset of language acquisition in early human development dramatically alters the capacity to learn language throughout life, independent of the sensory-motor form of the early experience.  相似文献   
933.
This study examined demographic characteristics, social competence, and behavior problems in clinic-referred children with gender identity problems in Toronto, Canada (N = 358), and Utrecht, The Netherlands (N = 130). The Toronto sample was, on average, about a year younger than the Utrecht sample at referral, had a higher percentage of boys, had a higher mean IQ, and was less likely to be living with both parents. On the Child Behavior Checklist (CBCL), both groups showed, on average, clinical range scores in both social competence and behavior problems. A CBCL-derived measure of poor peer relations showed that boys in both clinics had worse ratings than did the girls. A multiple regression analysis showed that poor peer relations were the strongest predictor of behavior problems in both samples. This study—the first cross-national, cross-clinic comparative analysis of children with gender identity disorder—found far more similarities than differences in both social competence and behavior problems. The most salient demographic difference was age at referral. Cross-national differences in factors that might influence referral patterns are discussed.  相似文献   
934.
This study investigated the acoustic characteristics of voicing in English fricative consonants produced by anterior aphasics and the effects of phonetic context on these characteristics. Three patients produced voiced and voiceless fricative-vowel syllables in isolation, following a voiced velar stop, and following a voiceless velar stop. Acoustic analyses were conducted of the amplitude and patterning of glottal excitation, as well as fricative noise duration. Results showed that, although the patients are able to coordinate the articulatory gestures for voicing in fricative consonants, they demonstrated abnormal patterns of glottal excitation in the amplitude measures, owing to weaker amplitudes of glottal excitation in voiced fricatives. Context effects failed to emerge because of dysfluent speech. These results suggest that the locus of the speech production deficit of anterior aphasics is not at the higher stages of phoneme selection or planning but rather in articulatory implementation, one related to laryngeal control.  相似文献   
935.
This work employs Evoked Potential techniques as 19 participants are confronted with sentences that have the potential to produce scalar implicatures, like in Some elephants have trunks. Such an Underinformative utterance is of interest to pragmatists because it can be considered to have two different truth values. It can be considered true when taken at face value but false if one were to treat Some with the implicature Not All. Two accounts of implicature production are compared. The neo-Gricean approach (e.g., Levinson, 2000) assumes that implicatures intrude automatically on the semantics of a term like Some. Relevance Theory (Sperber & Wilson, 1985/1996) assumes that implicatures are effortful and not automatic. In this experiment, the participants are presented with 25 Underinformative sentences along with 25 sentences that are Patently True (e.g. Some houses have bricks) and 25 that are Patently False (e.g. Some crows have radios). As reported in an earlier study (Noveck, 2001), Underinformative sentences prompt strong individual differences. Seven participants here responded true to all (or nearly all) of the Underinformative sentences and the remaining 12 responded false to all (or nearly all) of them. The present study showed that those who responded false to the Underinformative sentences took significantly longer to do so that those who responded true. The ERP data indicate that: (a) the Patently True and Patently False sentences prompt steeper N400's--indicating greater semantic integration--than the Underinformative sentences and that (b) regardless of one's ultimate response to the Underinformative sentences, the N400's were remarkably flat, indicating no particular reaction to these sentences. Collectively, the data are taken to show that implicatures are part of a late-arriving, effort-demanding decision process.  相似文献   
936.
The central issue addressed is whether there are electrophysiological markers for high-language proficiency in adults. Event-related brain potentials (ERPs) were recorded in 19 young adults who demonstrated either "normal" or "high" language proficiency. ERPs were obtained during a sentence-processing task and analyzed for specific response components elicited by different word types. The ERPs in the normal and high-language proficiency groups were similar for early sensory related processing but differed in the later components thought to be more closely related to lexical access and post-lexical processing. The findings for the ERP waveforms suggest that adults with high-language proficiency show slightly faster lexical access over left anterior brain regions for closed class items, and a reduced reliance on contextual information contained in sentences.  相似文献   
937.
The unification of mind: Integration of hemispheric semantic processing   总被引:1,自引:0,他引:1  
Seventy-six participants performed a visual half-field lexical decision task at two different stimulus onset asynchronies (50 or 750 ms). Word targets were primed either by a highly associated word (e.g., CLEAN-DIRTY), a weakly associated word (e.g., CLEAN-TIDY), or an unrelated word (e.g., CLEAN-FAMILY) projected to either the same or opposite visual field (VF) as the target. In the short SOA, RVF-left hemisphere primes resulted in high associate priming regardless of target location (ipsilateral or contralateral to the prime) whereas LVF-right hemisphere primes produced both high and low associate priming across both target location conditions. In the long SOA condition, contralateral priming patterns converged, demonstrating only high associate priming in both VF locations. The results of this study demonstrate the critical role of interhemispheric transfer in semantic processing and indicate a need to elaborate current models of semantic processing.  相似文献   
938.
Income is only weakly associated with both subjective well-being (SWB) and job satisfaction in the United States, a surprising finding in light of the importance placed on financial status in capitalistic societies. To explore this further, the authors examined intrinsic and extrinsic work orientations as potential moderators of the effects of financial compensation on SWB and job satisfaction. Master's of business administration students (N = 124) completed measures of work orientation and, 4 to 9 years later, reported their current salary, SWB, and job satisfaction. As predicted, individuals high in extrinsic orientation experienced higher SWB and job satisfaction to the degree that they earned more money, whereas those high in intrinsic orientation were lower on SWB at higher income levels. These findings are discussed in terms of the Values as Moderators Perspective of SWB and Cognitive Evaluation Theory.  相似文献   
939.
In two studies, the authors investigated guilt as a response to group-based advantage. Consistent with its conceptualization as a self-focused emotion, White guilt was based in self-focused beliefs in racial inequality. Thus, guilt was associated with belief in White privilege (Study 1) and resulted from seeing European Americans as perpetrators of racial discrimination (Study 2). Just as personal guilt is associated with efforts at restitution, White guilt was predictive of support for affirmative action programs aimed at compensating African Americans. White guilt was not, however, predictive of support for noncompensatory efforts at promoting equality, such as affirmative action programs that increase opportunities (Study 2). In contrast, the other-focused emotion of group-based sympathy was a more general predictor of support for different affirmative action policies. Our findings demonstrate the benefits and limits of group-based guilt as a basis of support for social equality and highlight the value of understanding the specific emotions elicited in intergroup contexts.  相似文献   
940.
Three studies address unresolved issues in value-behavior relations. Does the full range of different values relate to common, recurrent behaviors? Which values relate more strongly to behavior than others? Do relations among different values and behaviors exhibit a meaningful overall structure? If so, how to explain this? We find that stimulation and tradition values relate strongly to the behaviors that express them; hedonism, power, universalism, and self-direction values relate moderately; and security, conformity, achievement, and benevolence values relate only marginally. Additional findings suggest that these differences in value-behavior relations may stem from normative pressures to perform certain behaviors. Such findings imply that values motivate behavior, but the relation between values and behaviors is partly obscured by norms. Relations among behaviors, among values, and jointly among values and behavior exhibit a similar structure. The motivational conflicts and congruities postulated by the theory of values can account for this shared structure.  相似文献   
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