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181.
Many studies have suggested that emotional stimuli orient and engage attention. There is also evidence that animate stimuli, such as those from humans and animals, cause attentional bias. However, categorical and emotional factors are usually mixed, and it is unclear to what extent human context influences attentional allocation. To address this issue, we tracked participants' eye movements while they viewed pictures with animals and inanimate images (i.e., category) as focal objects. These pictures had either negative or neutral emotional valence, and either human body parts or nonhuman parts were near the focal objects (i.e., context). The picture's valence, arousal, position, size, and most of the low-level visual features were matched across categories. The results showed that nonhuman animals were more likely to be attended to and to be attended to for longer times than inanimate objects. The same pattern held for the human contexts (vs. nonhuman contexts). The effects of emotional valence, category, and context interacted. Specifically, in images with a negative valence, focal animals and objects with human context had comparable numbers of gaze fixations and gaze duration. These results highlighted the attentional bias to animate parts of a picture and clarified that the effects of category, valence, and picture context interacted to influence attentional allocation. 相似文献
182.
When a target appears in the same peripheral location as a previous cue, responding is typically delayed if the cue-target interval is relatively long. This phenomenon is termed inhibition of return (IOR) and has been suggested to reflect an attentional bias in favour of novel visual space. It has been demonstrated recently that IOR is much stronger in the far periphery than in the perifoveal visual field. The present study further investigated the neural mechanisms underlying this eccentricity effect of IOR with an event-related fMRI technique. The results demonstrated a stronger activation in visual cortex for perifoveal processing and a broader activation in multiple brain areas for peripheral processing. When IOR effects were compared between these two areas, a stronger activation of the fronto-parietal network was evidenced for perifoveal versus peripheral IOR, while the prefrontal cortex was more strongly involved in the peripheral IOR versus perifoveal IOR. These results suggest that different neural mechanisms are mediating the dissociable inhibitory functions between the perifoveal and peripheral visual field. 相似文献
183.
The event-related brain potential (ERP) technique was used to investigate the neural mechanism of non-target language processing in Chinese-English bilinguals. Participants were presented with a mixed list of Chinese and English words and required to make conceptual decisions for words in one language and ignore words in the other non-target language. Regardless of whether the nontarget word was in Chinese or English, the ERPs they elicited were modulated by word frequency, suggesting that their meaning had been accessed. The N400 peak was delayed in the English as the non-target language condition, probably because participants were less proficient in English. The results suggest that the non-target language can be processed during conceptual tasks with participants' proficiency in this language being a critical factor. 相似文献
184.
The present study used a sample of Chinese adolescents and validated a short-form of the Egna Minnen Betr?ffande Uppfostran: One's Memories of Upbringing (s-EMBU) assessing perceived parental rearing styles. A Chinese revision of the s-EMBU by the authors was administered to a total of 779 high school students, ages 11 to 19 years. Exploratory factor analysis with half of the sample yielded a three-factor solution of Rejection, Emotional Warmth, and Overprotection, accounting for 47.1% of the total variance onthe father form and 48.8% of the total variance on the mother form. Then, confirmatory factor analysis indicated a good fit of the three-factor model to the data in the other half of the sample. The three subscales consisted of 6, 6, and 7 items, respectively. Scores on these subscales had Cronbach alphas ranging from .71 to .81, indicating adequate internal consistency. These psychometric properties suggest its applicability for research with Chinese adolescents. 相似文献
185.
Previous studies have found a late frontal-central audiovisual interaction during the time period about 150-220 ms post-stimulus. However, it is unclear to which process is this audiovisual interaction related: to processing of acoustical features or to classification of stimuli? To investigate this question, event-related potentials were recorded during a words-categorization task with stimuli presented in the auditory-visual modality. In the experiment, congruency of the visual and auditory stimuli was manipulated. Results showed that within the window of about 180-210 ms post-stimulus more positive values were elicited by category-congruent audiovisual stimuli than category-incongruent audiovisual stimuli. This indicates that the late frontal-central audiovisual interaction is related to audiovisual integration of semantic category information. 相似文献
186.
In reading music, the acquisition of pitch information depends mostly on the spatial position of notes, hence more spatial processing, whereas the acquisition of temporal information depends mostly on the visual features of notes and object recognition. This study used both electrophysiological and behavioral methods to compare the processing of pitch and duration in reading single musical notes. It was observed that in the early stage of note reading, identification of pitch could elicit greater N1 and N2 amplitude than identification of duration at the parietal lobe electrodes. In the later stages of note reading, identifying pitch elicited a greater negative slow wave at parietal electrodes than did identifying note duration. The sustained contribution of parietal processes for pitch suggests that the dorsal pathway is essential for pitch processing. However, the duration task did not elicit greater amplitude of any early ERP components than the pitch task at temporal electrodes. Accordingly, a double dissociation, suggesting involvement of the dorsal visual stream, was not observed in spatial pitch processing and ventral visual stream in processing of note durations. 相似文献
187.
188.
This paper first discusses the relationship between Kullback–Leibler information (KL) and Fisher information in the context
of multi-dimensional item response theory and is further interpreted for the two-dimensional case, from a geometric perspective.
This explication should allow for a better understanding of the various item selection methods in multi-dimensional adaptive
tests (MAT) which are based on these two information measures. The KL information index (KI) method is then discussed and
two theorems are derived to quantify the relationship between KI and item parameters. Due to the fact that most of the existing
item selection algorithms for MAT bear severe computational complexity, which substantially lowers the applicability of MAT,
two versions of simplified KL index (SKI), built from the analytical results, are proposed to mimic the behavior of KI, while
reducing the overall computational intensity. 相似文献
189.
Jian XQ Wang KS Wu TJ Hillhouse JJ Mullersman JE 《Journal of abnormal child psychology》2011,39(6):773-782
Twin and family studies have shown that genetic factors play a role in the development of conduct disorder (CD). The purpose
of this study was to identify genetic variants associated with CD using a family-based association study. We used 4,720 single
nucleotide polymorphisms (SNPs) from the Illumina Panel and 11,120 SNPs from the Affymetrix 10K GeneChips genotyped in 155
Caucasian nuclear families from Genetic Analysis Workshop (GAW) 14, a subset from the Collaborative Study on the Genetics
of Alcoholism (COGA). 20 SNPs had suggestive associations with CD (p < 10−3), nine of which were located in known genes, including ADAM10 (rs383902, p = 0.00036) and CAMK2A (rs2053053, p = 0.00098). Our results were verified using the International Multi-Center ADHD Genetics Project (IMAGE) dataset. In conclusion,
we identified several loci associated with CD. Especially, the two genes (ADAM10 and CAMK2A) have been reported to be associated with Alzheimer’s disease, bipolar disorder and depression. These findings may serve
as a resource for replication in other populations. 相似文献
190.
This study investigated the effect of isoflavone aglycone (IA) on the learning and memory performance of senescence-accelerated mice, and explored its neural protective mechanism. Results showed that SAM-P/8 senescence-accelerated mice treated with IA performed significantly better in the Y-maze cognitive test than the no treatment control (P<0.05). The cortex AchE activity, serum SOD and GSH-Px activities were notably higher (P<0.05). MDA concentration and the β-secretase activity in the hippocampal tissue were both lower (P<0.05). Additionally, the number of hippocampal neurons was increased and cell morphology was significantly improved. Data suggested that IA could indirectly increase concentration of the cholinergic neural transmitter Ach through regulation of AchE, therefore improving the central cholinergic function and enhancing the learning and memory ability. By reducing the β-secretase activity, IA could decrease the formation and deposition of insoluble Adebris, relieve the resulted toxicity and damage to neurons, and thereby effectively protect the nervous system. 相似文献