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791.
The Cattell-Horn-Carroll theory of intelligence and the Spearman-Jensen hypothesis were applied to help interpret mean IQ differences among ethnic groups. The Cattell-Horn-Carroll theory classifies cognitive abilities on three strata, which differ by magnitude of generality including specific, broad, and general abilities. The Spearman-Jensen hypothesis advances the belief that mean IQ differences between African Americans and Euro-Americans occur as a function of the test's g loadings. Although IQ differences between African Americans and Euro-Americans occur, the differences should be larger on tests with higher g loadings and smaller on tests with lower g loadings. The analysis described in this paper may serve as the catalyst to encourage all intelligence test publishers to supply test users with data regarding mean IQ differences among various ethnic groups.  相似文献   
792.
The cytosolic posttranslational protein-modifying mechanism of monoADP-ribosylation has been implicated in long-term potentiation, a synaptic model of memory formation. The current study investigated the effect of inhibiting mono(ADP-ribosyl) transferase on memory for the passive avoidance task in day-old chicks (white Leghorn-black Australorp). Various doses of novobiocin or menadione sodium bisulfite were administered intracranially at different times before or after training. Control chicks were administered saline at matched times. Novobiocin (650 microM) or menadione sodium bisulfite (250 microM) administered between 5.0 min pretraining and 2.5 min posttraining was found to cause a persistent loss of retention from 120 min posttraining. These data provide the first demonstration that monoADP-ribosylation is required for the maintenance of long-term memory. Furthermore, the temporal characteristics of the memory loss caused by monoADP-ribosylation inhibition appears to exclude this mechanism as a downstream effect of the well-established nitric oxide activity previously shown to occur within 40 min of passive avoidance training.  相似文献   
793.
794.
This study examines the processing of a specific linguistic distinction, the mass/count distinction, in patients suffering from Alzheimer’s disease (AD) and mild cognitive impairment (MCI). Fourteen AD and 10 MCI subjects were tested using a sentence grammaticality judgement task where grammaticality violations were caused by determiner–noun mismatches, as well as a sentence–picture matching task to assess their ability to access mass and count readings of dual nouns. Considerable heterogeneity was observed within each subject group, and performance across groups was almost identical. It is concluded that a combination of linguistic and attentional and/or learning factors are responsible for the range of impairments; specifically, a subset of subjects exhibit no linguistic nor attentional/learning impairment, another subset exhibit only an attentional and/or learning impairment but no linguistic impairment, and a third subset (comprising more than half of the subjects included in this study) exhibit a linguistic impairment. It is postulated that the latter group have difficulty processing sense extensions in metonymous nouns. It is further claimed that, at least within the limits of the study, language impairments can be of the same severity and nature across AD and MCI subjects.  相似文献   
795.
The objective of the present study was to investigate the comparative criterion‐related validity of different statistical operationalizations of group general cognitive ability (i.e., mean, maximum, and minimum) as a function of task type based on Steiner's (1966, 1972) task typology. In contrast to recent investigations, we hypothesized that, regardless of task type, the mean of group members’ general cognitive ability would predict group performance as well as or better than other statistical operationalizations of group general cognitive ability. We conducted a laboratory study where 157 four‐person groups worked on 4 tasks that conformed to Steiner's typology (additive, compensatory, conjunctive, and disjunctive). The results indicate that the mean was the strongest predictor of group performance across all 4 task types and, in particular, was significantly stronger than the maximum and minimum on both the disjunctive and conjunctive tasks.  相似文献   
796.
This study examined short‐term attachment stability and sought to identify predictors of stability and change within a sample characterized by fathers' alcoholism. Results suggest moderate stability of attachment classifications (60% for mothers, 53% for fathers) from 12 to 18 months. Higher paternal and maternal alcohol symptoms, maternal depression, and maternal antisocial behavior were found in families with stable insecure mother–infant attachment compared to those who were stable secure. Mother–infant stable insecurity was associated with higher levels of maternal negative affect expression during play. Father–infant stable insecurity was associated with lower levels of paternal positive affect expression and decreased sensitivity during play. Stable insecure children also had higher levels of negative affect during parent–infant interactions and higher negative emotionality during other episodes compared to stable secure children. Results indicate that infants who were insecure at both time points had the highest constellation of family risk characteristics.  相似文献   
797.
It has been suggested that representing an action through observation and imagery share neural processes with action execution. In support of this view, motor-priming research has shown that observing an action can influence action initiation. However, there is little motor-priming research showing that imagining an action can modulate action initiation. The current study examined whether action imagery could prime subsequent execution of a reach and grasp action. Across two motion analysis tracking experiments, 40 participants grasped an object following congruent or incongruent action imagery. In Experiment 1, movement initiation was faster following congruent compared to incongruent imagery, demonstrating that imagery can prime the initiation of grasping. In Experiment 2, incongruent imagery resulted in slower movement initiation compared to a no-imagery control. These data show that imagining a different action to that which is performed can interfere with action production. We propose that the most likely neural correlates of this interference effect are brain regions that code imagined and executed actions. Further, we outline a plausible mechanistic account of how priming in these brain regions through imagery could play a role in action cognition.  相似文献   
798.
Discrimination and violence targeting people perceived as gender nonconforming have been linked to a range of negative health outcomes, and large-scale representative data are needed to begin population surveillance of associated health disparities. A brief self-report measure of gender expression as perceived by others was tested using cognitive interviewing methods in a diverse sample of 82 young adults aged 18–30 years, recruited from the New England region in the U.S. Results identified themes related to item clarity, gender expression variation, undesirability of highest or lowest ends of item range, and tension between self and others’ perceptions. The item performed as expected and is recommended for use on studies of health disparities, including statewide and national public health surveillance tools.  相似文献   
799.
In two experiments, bilingual (Urdu and English) 5- and 6-year-old children outperformed their monolingual (English) peers when asked to detect grammatically incorrect sentences on a syntactic awareness test. This result occurred when children were tested in English (Experiment 1) and when they were tested in English or in Urdu (Experiment 2). Bilingual children aged 3 and 4 were better at detecting grammatically incorrect sentences than their monolingual peers, but only when tested in Urdu. However, no significant differences appeared in monolingual and bilingual children's ability to detect grammatically correct sentences, suggesting that both grammatically correct and incorrect sentences should be used to obtain an accurate measure of syntactic awareness. The issue of whether it is bilingualism or the properties of a language that affect syntactic awareness is considered.  相似文献   
800.
The Oxford Happiness Questionnaire (OHQ) was developed by Hills and Argyle (2002) to provide a more accessible equivalent measure of the Oxford Happiness Inventory (OHI). The aim of the present study was to examine the internal consistency reliability, and construct validity of this new instrument alongside the Eysenckian dimensional model of personality. The Oxford Happiness Questionnaire was completed by a sample of 131 undergraduate students together with the abbreviated form of the Revised Eysenck Personality Questionnaire. The data demonstrated good internal consistency reliability (alpha = .92) and good construct validity in terms of positive association with extraversion (r = .38 p < .001) and negative association with neuroticism (r = −.57 p < .001). The kind of happiness measured by the OHQ is clearly associated with stable extraversion.  相似文献   
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