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991.
The current study examined the longitudinal stability and invariance of psychopathic traits in a large community sample of male twins from ages 17 to 23. Participants were assessed across 6 years to gauge the stability and measurement invariance of the Minnesota Temperament Inventory (MTI), a Cleckley-based measure of psychopathic personality traits, and how family functioning and externalizing behavior were linked to these traits. A latent variable approach was used to model the structure of the MTI and provide a statistical test of measurement invariance across time. The results revealed support for invariance and moderate to strong stability of the MTI factors, which showed significant associations with the external correlates in late adolescence but not early adulthood.  相似文献   
992.

Objective

The purpose of this article is to introduce a new assessment designed to measure the orofacial abilities of children who stutter (CWS), the Movement, Articulation, Mandibular and Sensory Awareness (MAMS) Orofacial Assessment. The new instrument was developed and validated to measure orofacial abilities in a comprehensive manner.

Design

A group of 43 CWS (mean age 13.10 years, S.D. 2.10 years) and a control group of 32 fluent children (mean age 13.4 years, S.D. 2.6 years) were tested with the new tool. It was hypothesized, that (a) the MAMS is a reliable and valid instrument to measure orofacial abilities in CWS, (b) fluent children have better orofacial abilities than CWS and (c) that the therapy outcome of CWS depend on their orofacial abilities.

Results

The MAMS Orofacial Assessment proved to be a valid and reliable instrument to assess orofacial abilities. Compared with their fluent peers, CWS had significantly worse orofacial abilities. CWS with better orofacial abilities had a better prognosis for therapy outcome.

Conclusions

The new instrument is a reliable and valid tool to measure orofacial abilities and MAMS distinguishes CWS and controls. Orofacial abilities are one set of factors that influence therapy outcome for CWS.Educational objectives: The reader will get an overview over of the literature on orofacial abilities in people who stutter and will learn about and be able to (1) describe different characteristics of orofacial abilities, (2) use the MAMS Orofacial Assessment in the diagnostic process for CWS and for research purposes, and (3) interpret the results of the MAMS to use them for therapy planning.  相似文献   
993.
The role of physical and relational aggression in adolescents' friendship selection was examined in a longitudinal sample of 274 Chilean students from 5th and 6th grade followed over 1 year. Longitudinal social network modeling (SIENA) was used to study selection processes for aggression while influence processes were controlled for. Furthermore, the effects of network characteristics (i.e., reciprocity and transitivity), gender, and social status on friendship selection were examined. The starting assumption of this study was that selection effects based on aggression might have been overestimated in previous research as a result of failing to consider influence processes and alternative characteristics that steer friendship formation. The results show that selection effects of both physical and relational aggression disappeared when network effects, gender, and social status were taken into account. Particularly gender and perceived popularity appeared to be far more important determinants of friendship selection over time than aggression. Moreover, a peer influence effect was only found for relational aggression, and not for physical aggression. These findings suggest that similarity in aggression among befriended adolescents can be considered to be mainly a by-product rather than a leading dimension in friendship selection.  相似文献   
994.
Our representation of peripersonal space does not always accurately reflect the physical world. An example of this is pseudoneglect, a phenomenon in which neurologically normal individuals bisect to the left of the veridical midpoint, reflecting an overrepresentation of the left portion of space compared with the right one. Consistent biases have also been observed in the vertical and radial planes. It is an open question whether these biases depend on normal visual experience for their occurrence. Here we systematically investigated this issue by testing blindfolded sighted and early blind individuals in a haptic line bisection task. Critically, we found a robust leftward bias in all participants. In the vertical and radial planes, sighted participants showed a consistent downward and proximal bias. Conversely, the directional bias in blind participants was dependent on the final movement direction; thus, there was no general bias in either direction. These findings are discussed in terms of different reference frames adopted by sighted and blind participants when encoding space.  相似文献   
995.
The purpose of this study was to examine the effects of expertise on motion anticipation. We conducted 2 experiments in which novices and expert pilots viewed simulated aircraft landing scenes. The scenes were interrupted by the display of a black screen and then started again after a forward or backward shift. The participant's task was to determine whether the moving scene had been shifted forward or backward. A forward misjudgment of the final position of the moving scene was interpreted as a representational momentum (RM) effect. Experiment 1 showed that an RM effect was detected only for experts. The lack of motion anticipation on the part of novices is a surprising result for the RM literature. It could be related to scene unfamiliarity, encoding time, or shift size. Experiment 2 was run with novices only. It was aimed at testing the potential impact of 2 factors on the RM effect: scene encoding time and shift size. As a whole, the results showed that encoding time and shift size are important factors in anticipation processes in realistic dynamic situations.  相似文献   
996.
Humans show a global advantage when processing hierarchical visual patterns, and they detect the global level of stimulus structure more accurately and faster than the local level in several stimulus contexts. By contrast, capuchins (Cebus apella) and other monkey species show a strong local advantage. A key factor which, if manipulated, could cause an inversion of this effect in monkeys is still to be found. In this study, we examined whether it was possible to induce attention allocation to global and local levels of perceptual analysis in capuchin monkeys and if by doing so, their local dominance could be reversed. We manipulated attentional bias using a matching-to-sample (MTS) task where the proportion of trials requiring global and local processing varied between conditions. The monkeys were compared with humans tested with the same paradigm. Monkeys showed a local advantage in the local bias condition but a global advantage in the global bias condition. The role of attention in processing was confined to the local trials in a first phase of testing but extended to both local and global trials in the course of task practice. Humans exhibited an overall global dominance and an effect of attentional bias on the speed of processing of the global and local level of the stimuli. These results indicate a role for attention in the processing of hierarchical stimuli in monkeys and are discussed in relation to the extent to which they can explain the differences between capuchin monkeys and humans observed in this and other studies.  相似文献   
997.
The action-based model of dissonance and recent advances in neuroscience suggest that commitment to action should cause greater relative left frontal cortical activity. Two experiments were conducted in which electroencephalographic activity was recorded following commitment to action, operationalized with a perceived choice manipulation. Perceived high as compared to low choice to engage in the action, regardless of whether it was counterattitudinal or proattitudinal, caused greater relative left frontal cortical activity. Moreover, perceived high as compared to low choice caused attitudes to be more consistent with the action. These results broaden the theoretical reach of the action-based model by suggesting that similar neural and motivational processes are involved in attitudinal responses to counterattitudinal and proattitudinal commitments.  相似文献   
998.
Eye movements of 30 4-month-olds were tracked as infants viewed animals and vehicles in “natural” scenes and, for comparison, in homogeneous “experimental” scenes. Infants showed equivalent looking time preferences for natural and experimental scenes overall, but fixated natural scenes and objects in natural scenes more than experimental scenes and objects in experimental scenes and shifted fixations between objects and contexts more in natural than in experimental scenes. The findings show how infants treat objects and contexts in natural scenes and suggest that they treat more commonly used experimental scenes differently.  相似文献   
999.

Background

An infant's early environment has an important influence on their development. For example, the sensitivity and warmth of a mother's responses towards her infant is associated with the infant's later socio-emotional development. However, it is less clear whether maternal responses are associated with the infant's later cognitive development.

Method

We used data from a large UK cohort study to investigate the association between non-verbal maternal responses and later infant development and IQ. Maternal responses were rated at 12 months during an observed mother–infant interaction. Infant development was assessed using the Griffiths scales at 18 months and IQ at 4 years was assessed using the Wechsler Preschool and Primary Scale of Intelligence (WPPSI). Data on the infant's developmental level at 6 months (prior to the maternal response ratings) was also available. The complete case sample comprised 732 mother–infant pairs.

Results

There was evidence for an association between positive maternal responses and infant development at 18 months. After adjusting for infant developmental level at 6 months and other confounders, we found a difference of 0.25 standard deviations (coef 2.0, 95% CI (0.8–3.2), p = 0.002) on the Griffiths scales between infant's whose mothers showed positive compared to neutral non-verbal responses at 12 months. However, an association between positive maternal responses and IQ at 4 years diminished following adjustment for maternal educational attainment.

Conclusion

The results provide evidence that positive maternal responses are associated with improved development in infants at 18 months. However, the association between maternal response and IQ at 4 years may be explained by higher educational attainment in mothers who show positive responses. Future studies are needed to explore the influence of maternal responses on different aspects of infant development as well as the role of maternal factors such as education.  相似文献   
1000.

Objective

This study examined the contributions of maternal bids for joint attention, relationship quality, and infant characteristics, to individual differences in infants’ parallel and joint attention.

Method

Fifty-two 10-month-olds and their mothers were assessed in order to investigate concurrent predictors of infant parallel attention, responding to joint attention, and initiating joint attention.

Results

Parallel attention was predicted by infants’ higher mental development, low expression of negative emotionality, and maternal entertaining behaviors. Responding to joint attention was marginally predicted by total maternal bids for joint attention. Initiating joint attention was predicted by the infants’ low expression of negative emotionality, as well as marginally predicted by fewer maternal teaching behaviors.

Conclusion

These results further the understanding of the factors influencing infant parallel as well as joint attention.  相似文献   
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