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91.
92.
Fetal alcohol syndrome and the developing socio-emotional brain   总被引:1,自引:0,他引:1  
Fetal alcohol syndrome (FAS) is currently recognized as the most common known cause of mental retardation, affecting from 1 to 7 per 1000 live-born infants. Individuals with FAS suffer from changes in brain structure, cognitive impairments, and behavior problems. Researchers investigating neuropsychological functioning have identified deficits in learning, memory, executive functioning, hyperactivity, impulsivity, and poor communication and social skills in individuals with FAS and fetal alcohol effects (FAE). Investigators using autopsy and brain imaging methods have identified microcephaly and structural abnormalities in various regions of the brain (including the basal ganglia, corpus callosum, cerebellum, and hippocampus) that may account for the neuropsychological deficits. Results of studies using newer brain imaging and analytic techniques have indicated specific alterations (i.e., displacements in the corpus callosum, increased gray matter density in the perisylvian regions, altered gray matter asymmetry, and disproportionate reductions in the frontal lobes) in the brains of individuals prenatally exposed to alcohol, and their relations with brain function. Future research, including using animal models, could help inform our knowledge of brain-behavior relations in the context of prenatal alcohol exposure, and assist with early identification and intervention.  相似文献   
93.
Current theory assumes that individuals only use information from the immediate environment to perform relative arrival-time judgment tasks. This article presents a theoretical analysis of the memory requirements of this task. The authors present an analysis of the inputs to the memory system and the processes that map those inputs onto outputs. The analysis generates a set of predictions regarding the specificity of transfer and the role of context during learning. In 3 experiments, participants decided whether pairs of aircraft would violate a minimum separation standard or pass each other safely. Participants were presented with pairs of aircraft in which properties of the pair varied along 3 structural and 3 surface dimensions. Contexts were defined by the co-occurrence of specific values along stimulus dimensions and the use of a neutral label. The results suggest that transfer was limited by the dimensions that were varied in training and the context in which those dimensions were varied. The discussion focuses on the problems that complex tasks like relative judgment pose for associative learning mechanisms and the development of precise models of cognition.  相似文献   
94.
Three experiments are reported in which a total of 182 old and 193 young adults recalled sequences of digits presented visually in silence or accompanied by office noise. In each experiment, an effect of irrelevant sound was found-that is, a reduction of serial recall due to auditory distraction. Old adults exhibited poorer serial recall than did young adults, but the irrelevant-sound effect was equivalent in both age groups. This was true even though the sound level of the irrelevant sound was adjusted to each individual's hearing capability, and the effect remained whether or not the difficulty of the serial recall task was equated across age groups. These results are problematic for the inhibitory deficit theory of cognitive aging, which predicts that old adults should be more susceptible to auditory distraction than are young adults.  相似文献   
95.
In 4 chronometric experiments, influences of spoken word planning on speech recognition were examined. Participants were shown pictures while hearing a tone or a spoken word presented shortly after picture onset. When a spoken word was presented, participants indicated whether it contained a prespecified phoneme. When the tone was presented, they indicated whether the picture name contained the phoneme (Experiment 1) or they named the picture (Experiment 2). Phoneme monitoring latencies for the spoken words were shorter when the picture name contained the prespecified phoneme compared with when it did not. Priming of phoneme monitoring was also obtained when the phoneme was part of spoken nonwords (Experiment 3). However, no priming of phoneme monitoring was obtained when the pictures required no response in the experiment, regardless of monitoring latency (Experiment 4). These results provide evidence that an internal phonological pathway runs from spoken word planning to speech recognition and that active phonological encoding is a precondition for engaging the pathway.  相似文献   
96.
Ben-Ari A  Lavee Y 《Family process》2007,46(3):381-393
An important aspect of Israeli life is its continuous state of conflict with the neighboring Palestinian people and Arab countries. Given that security-related stress is so intensely experienced by all Israeli residents, we examined the effects of daily fluctuations in security-related stress on dyadic closeness among Jewish and Arab couples. Time sampling approach was used to study repeated sequences of associations between stress and dyadic closeness. Data were collected from 188 Jewish and 93 Arab couples by means of daily diaries. Hierarchical multivariate linear modeling was used to analyze the data. The findings indicate that stress results in increasing distance between intimate partners, but the effect varies with the level of marital quality and socioethnic affiliation.  相似文献   
97.
This study demonstrates that experience and development interact to influence the "cross-race effect." In a multination study (n=245), Caucasian children and adults of European ancestry living in the United States, Norway, or South Africa, as well as biracial (Caucasian-African American) children and adults living in the United States, were tested for recognition of Asian, African, and Caucasian faces. Regardless of national or biracial background, 8- to 10-year-olds, 12- to 14-year-olds, and adults recognized own-race faces more accurately than other-race faces, and did so to a similar extent, whereas 5- to 7-year-olds recognized all face types equally well. This same developmental pattern emerged for biracial children and adults. Thus, early meaningful exposure did not substantially alter the developmental trajectory. During young childhood, developmental influences on face processing operate on a system sufficiently plastic to preclude, under certain conditions, the cross-race effect.  相似文献   
98.
We investigated whether the "unity assumption," according to which an observer assumes that two different sensory signals refer to the same underlying multisensory event, influences the multisensory integration of audiovisual speech stimuli. Syllables (Experiments 1, 3, and 4) or words (Experiment 2) were presented to participants at a range of different stimulus onset asynchronies using the method of constant stimuli. Participants made unspeeded temporal order judgments regarding which stream (either auditory or visual) had been presented first. The auditory and visual speech stimuli in Experiments 1-3 were either gender matched (i.e., a female face presented together with a female voice) or else gender mismatched (i.e., a female face presented together with a male voice). In Experiment 4, different utterances from the same female speaker were used to generate the matched and mismatched speech video clips. Measuring in terms of the just noticeable difference the participants in all four experiments found it easier to judge which sensory modality had been presented first when evaluating mismatched stimuli than when evaluating the matched-speech stimuli. These results therefore provide the first empirical support for the "unity assumption" in the domain of the multisensory temporal integration of audiovisual speech stimuli.  相似文献   
99.
Priming of affective word evaluation by pictures of faces showing positive and negative emotional expressions was investigated in two experiments that used a double task procedure where participants were asked to respond to the prime or to the target on different trials. The experiments varied between-subjects the prime task assignment and the prime-target interval (SOA, stimulus onset asynchrony). Significant congruency effects (that is, faster word evaluation when prime and target had the same valence than when they were of opposite valence) were observed in both experiments. When the prime task oriented the subjects to an affectively irrelevant property of the faces (their gender), priming was observed at SOA 300 ms but not at SOA 1000 ms (Experiment 1). However, when the prime task assignment explicitly oriented the subjects to the valence of the face, priming was observed at both SOA durations (Experiment 2). These results show, first, that affective priming by pictures of facial emotion can be obtained even when the subject has an explicit goal to process a non-affective property of the prime. Second, sensitivity of the priming effect to SOA duration seems to depend on whether it is mediated by intentional or unintentional activation of the valence of the face prime.  相似文献   
100.
The aim of the present study was to validate a reduced Spanish version of the Negative Acts Questionnaire (NAQ; Einarsen & Raknes, 1997). This instrument, which has been widely used in various studies, was developed to measure workplace bullying. Two samples, the first comprising 352 employees from 11 organizations, and the second comprising victims of bullying who were recruited from 15 Spanish associations against bullying, participated in the study. Exploratory factor analysis conducted with the data from the first sample revealed a two-factor solution that accounted for 63.3% of the total variance. The data from the second sample were used for confirmatory factor analyses to compare three structure models of the NAQ (one factor, two independent factors, and two correlated factors). The results indicate that the correlated two-factor model provided the best fit to the data (chi2/df = 2.1, CFI = .93, GFI = .95, RMR = .04, RMSEA = .06, AIC = 215.4). Reliability analysis showed that this 14-item Spanish version had high internal consistency. Significant correlations between the NAQ and its dimensions and diverse health and perceived stress scales were found, which provided evidence of construct validity. Taken conjointly, the results of this study support the use of the Spanish version of the reduced NAQ in future research.  相似文献   
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