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Many studies using N2pc as a marker of attentional capture have demonstrated top-down contingent capture for salient color singletons: Among all salient cues that are not predictive of the target location, only cues similar to searched-for target features, and thus, matching to the top-down attentional control settings capture attention. This is reflected in matching cue's elicitation of an N2pc and a cueing effect in behavior, and the absence of the corresponding effects for non-matching cues (with features dissimilar to that of the searched-for targets). Yet, with abrupt-onset cues, corresponding evidence is missing, inviting speculations about the potential of abrupt-onset cues to capture attention followed by quick suppression within the target displays. Here, we used two types of abrupt-onset cues to test if capture by such cues also adheres to the contingent-capture principle: matching abrupt-onset cues with a color similar to the top-down control settings and non-matching abrupt-onset cues with a color different from all searched-for targets. With the help of these cues, top-down contingent capture was supported. Only matching abrupt-onset cues elicited an N2pc and a behavioral cueing effect. Depending on the exact side conditions, non-matching cues either elicited no N2pc or a PD (i.e., evidence of active suppression). Results are discussed against the background of competing theories on attention capture by abrupt-onset cues.  相似文献   

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The study of visually elicited event-related potentials (ERPs) detected at posterior recording sites during visual search has enormously advanced our knowledge about how and when visuo-spatial attention locks onto one or more laterally presented target objects. The N2pc component to lateral targets has been pivotal to further our understanding of the mechanisms and time course of target selection in visual search. However, the N2pc cannot track visuo-spatial attention deployment to targets displayed along the vertical midline. Here, we introduce a new ERP marker (N2pcb component) that is elicited during the selection of such midline targets. In line with retinal and callosal projections from striate to ventral extrastriate cortex, this component reflects an enhanced negativity elicited by midline targets over both posterior hemispheres. By comparing the attentional selection of lateral and midline targets in a singleton search condition and a feature search condition, we show that the N2pcb is triggered at the same time as the N2pc to lateral targets, and shows the same onset latency difference between singleton and feature search. We conclude that the N2pcb and N2pc components reflect the same attentional target selection processes in visual search.  相似文献   

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Prolonged exposure (PE) has been proved as an efficacious psychological treatment for post‐traumatic stress disorder (PTSD). There are mainly two changed formats of PE: the modified PE (mPE) and the PE combined with drug (PE/d). Symptom reduction following these two PE training formats has been reported in the patients with PTSD. However, very little is focusing on the direct comparison of mPE + PE/d and PE. Therefore, this paper aims to compare the mPE + PE/d with PE on the PTSD treatment effect and the dropout rate directly through the meta‐analysis. Eighteen studies with total sample size of 1,397 met the final inclusion criteria. The results showed that mPE + PE/d had significantly lower posttreatment PTSD severity than control group (relaxation, wait list, etc.). There was no significant difference between mPE + PE/d and PE on the posttreatment, the follow‐up PTSD score, and the posttreatment dropout rate. Compared with PE, lower PTSD symptoms and marginally lower dropout rate following the treatment were observed in the PE/d group. PE/d yielded a significantly larger effect size than mPE when compared with PE on the posttreatment PTSD symptom severity. The significance of the above results would not be changed even if studies causing high heterogeneity were removed. Although PE/d enhanced treatment effect and lowered dropout rate when compared with PE, it was still insufficient to draw the conclusion that formats of adjustments would specifically improve the implementation of PE. Further studies are warranted to develop an easily accomplished and efficacy‐guaranteeing PE programme for PTSD patients.  相似文献   

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The N2pc ERP component has been widely used as a measure of lateralized visual attention. It is characterized by a negativity contralateral to the attended location or target, and it is thought to reflect contralaterally enhanced processing of attended information in intermediate to high levels of the ventral visual pathway. Given that the receptive fields in these areas often extend a few degrees into the ipsilateral hemifield, we might expect that near-midline stimuli would be processed by both the contralateral and ipsilateral hemispheres, resulting in a diminished N2pc. However, little is known about the effect of eccentricity on the N2pc component. To address this gap in knowledge, we recorded the EEG while participants performed a discrimination task with stimuli presented at one of five eccentricities (0°, 0.05°, 1°, 2°, 4° and 8° between the inner edge of the stimulus and the midline). We found that the N2pc amplitude remained relatively constant across eccentricities, including when the inner edge was at the midline, except that N2pc amplitude was reduced by more than 50% at the greatest eccentricity (8°). We also examined the contralateral positivity that often follows the N2pc. This positivity became progressively larger, and the transition from negative to positive occurred progressively later, as the eccentricity increased. These findings suggest that future experiments looking at the N2pc can use near-midline stimuli without compromising the N2pc amplitude, but should avoid large eccentricities. Implications about the neural generators of the N2pc are also discussed.  相似文献   

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The N2pc component of the event-related potentials is assumed to indicate attentional filtering processes during visual search tasks. In this study, we investigated the effects of physical disparity between a target stimulus and distracter stimuli and discrimination difficulty of the target item, on N2pc component by recording event-related potentials (ERPs) while subjects completed a visual search task. In the visual search task, we presented a round array of stimuli and manipulated the color disparity between the target and distracters and the discriminative difficulty of the target's form. The results showed that higher amplitude of N2pc was elicited in the high color disparity condition compared to the low disparity condition. However, no significant effect was found for the discriminative difficulty. The results suggested that the N2pc component could be modulated by the physical disparity between the target item and the distracters in the searching processes, which most likely reflects allocation of attention to select an object based on the perceptual saliency of that object.  相似文献   

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Obesity and COVID‐19 are both worldwide epidemics now. There may be some potential relationships between them, but little is known. This study was done to explore this relationship through literature search, systematic review, and meta‐analysis. Pubmed, Embase, WOS, Cochrane, CNKI, Wanfang, and Sinomed databases were searched to collect literature concerning obesity and COVID‐19. Systematic review and meta‐analysis were conducted after literature screening, quality assessment, and data extraction. A total of 180 articles were initially searched after duplicate removal, and 9 were finally included in our analysis. Results show that severe COVID‐19 patients have a higher body mass index than non‐severe ones (WMD = 2.67; 95% CI, 1.52‐3.82); COVID‐19 patients with obesity were more severely affected and have a worse outcome than those without (OR = 2.31; 95% CI, 1.3‐4.12). Obesity may aggravate COVID‐19.  相似文献   

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In the present study, we used high‐density EEG during a visual search task to investigate the dynamics of spatial attention to fear‐relevant targets and background stimuli in small animal phobia during a visual search task. Twenty‐five spider fearful (22 females) and 25 healthy nonfearful participants (19 females) were measured, while searching for discrepant objects in visual arrays. Compared to nonfearful participants, s pider fearful individuals showed a more enhanced posterior N2pc to spider (vs. butterfly) targets in an array of flowers. Furthermore, spider fearful participants showed enhanced hypervigilance for all presented stimuli compared to controls as reflected by enhanced N1 amplitudes (160–200 ms). Our findings provide neural evidence for early, enhanced selective spatial attention for fear‐relevant stimuli.  相似文献   

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This meta‐analysis addresses the question of whether expressive writing shows an effect on reducing depressive symptoms. It focuses on samples of physically healthy adults with varying degrees of stress but without posttraumatic stress disorder. A total of 39 randomized controlled trials with 64 intervention‐control group comparisons were obtained through keyword search in databases and backward search. Expressive writing did not yield significant long‐term effects on depressive symptoms. However, effects were larger when the number of sessions was higher and when the writing topic was more specific. The results of this meta‐analysis did not support the effectiveness of brief, self‐directed expressive writing as an intervention that decreases depressive symptoms in physically healthy adults with varying degrees of psychological stress. Future research should examine whether longer, more directed writing interventions with additional therapeutic support would lead to different results.  相似文献   

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Competing theories regarding the neural mechanism underlying the N2pc suggest that it reflects target enhancement or distractor suppression, but we suggest a different theory. In our study, participants viewed a bilateral dual‐stream rapid serial visual presentation (RSVP). Each trial had either one or two targets (T1, T2) presented either in the same or different streams. We found that the N2pc elicited by T1 was not affected by an immediately following T2 at the same location. However, if T2 was on the opposite hemifield, a second N2pc was elicited. These results suggest that the N2pc reflects neural processes involved in localizing a target to initiate the deployment of attention, rather than the sustained enhancement of processing at that location or distractor inhibition. We have created a computational model of a convergent gradient‐filter model of attention that reproduces the observed event‐related potential traces and makes five testable predictions to be addressed in future work.  相似文献   

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Cytochrome P450 2A6 (CYP2A6) is an enzyme responsible for the metabolism of nicotine and some tobacco‐specific carcinogens (such as N‐nitrosamines). CYP2A6 genetic variations are associated with the activity of the CYP2A6 enzyme, which affects smoking behavior and the rate at which some tobacco‐specific carcinogens are metabolized, which in turn determines the incidence of lung cancer. Several studies have investigated the relationship between CYP2A6 genotypes and lung cancer; however, the results are controversial. In this meta‐analysis, we searched for all studies on the association between CYP2A6 genotypes and lung cancer indexed in the MEDLINE, PubMed, Embase, China Biological Medicine, and Wanfang databases from January 1, 1966 to August 1, 2011. The pooled odds ratios (ORs) for one CYP2A6 mutant allele and two CYP2A6 mutant alleles, in comparison with the wild‐type CYP2A6 gene, were 0.82 [95% confidence interval (CI) = 0.73–0.92] and 0.57 (95% CI = 0.48–0.68), respectively. Furthermore, in two studies of participants who were all smokers, the associations of one CYP2A6 mutant allele and two CYP2A6 mutant alleles with reduced risk of lung cancer were strengthened, and the pooled ORs were 0.71 (95% CI = 0.58–0.87) and 0.47 (95% CI = 0.35–0.62), respectively. However, we did not find statistically significant relationships between CYP2A6 genotypes and lung cancer in studies that included both never smokers and smokers (pooled ORone CYP2A6 mutant allele = 0.88, 95% CI = 0.76–1.01; pooled ORtwo CYP2A6 mutant alleles = 0.61, 95% CI = 0.35–1.06). The results of this meta‐analysis suggest that the reduced‐activity CYP2A6 genotype may decrease the risk of lung cancer in smokers only. Environ. Mol. Mutagen., 2013. © 2012 Wiley Periodicals, Inc.  相似文献   

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Achondroplasia is a genetic disorder that results in disproportionate short stature. The true prevalence of achondroplasia is unknown as estimates vary widely. This systematic literature review and meta‐analysis was conducted to better estimate worldwide achondroplasia birth prevalence. PubMed, Embase, Scielo, and Google Scholar were searched, complemented by manual searching, for peer‐reviewed articles published between 1950 and 2019. Eligible articles were identified by two independent researchers using predefined selection criteria. Birth prevalence estimates were extracted for analysis, and the quality of evidence was assessed. A meta‐analysis using a quality effects approach based on the inverse variance fixed effect model was conducted. The search identified 955 unique articles, of which 52 were eligible and included. Based on the meta‐analysis, the worldwide birth prevalence of achondroplasia was estimated to be 4.6 per 100,000. Substantial regional variation was observed with a considerably higher birth prevalence reported in North Africa and the Middle East compared to other regions, particularly Europe and the Americas. Higher birth prevalence was also reported in specialized care settings. Significant heterogeneity (Higgins I2 of 84.3) was present and some indication of publication bias was detected, based on visual asymmetry of the Doi plot with a Furuya‐Kanamori index of 2.73. Analysis of pooled data from the current literature yields a worldwide achondroplasia birth prevalence of approximately 4.6 per 100,000, with considerable regional variation. Careful interpretation of these findings is advised as included studies are of broadly varying methodological quality.  相似文献   

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Attentional capture by salient distractors has been confirmed by the occurrence of an N2pc to the salient distractor. To clarify some failures to replicate this finding, we varied target predictability to induce different search modes. In the unpredictable target condition, the target shape varied randomly from trial to trial, favoring singleton detection mode. In the predictable target condition, the target shape remained the same in a block of trials, favoring feature search mode. With unpredictable targets, we observed an N2pc toward the salient color distractor, confirming attentional capture in singleton search mode. With predictable targets, there was no N2pc to the salient distractor, but a distractor positivity (Pd), suggesting distractor suppression. Also, differences emerged in the topographic segmentation of N2pc and Pd. Further, the amplitude of the N2pc toward the target was larger with predictable than with unpredictable targets.  相似文献   

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The study investigated several associations between depression and intrusive negative autobiographical memories. A systematic literature search identified 23 eligible studies (N = 2,582), which provided 59 effect sizes. Separate meta‐analyses indicated that depression was moderately, positively associated with intrusive memory frequency, memory distress, maladaptive memory appraisals, memory avoidance, and memory rumination. Intrusive memory vividness was not significantly associated with depression. There were insufficient data to examine the relationship between depression and memory vantage perspective. Between‐study heterogeneity was high for intrusive memory frequency and memory avoidance, and the percentage of females in studies significantly moderated the relationship between these variables and depression. An additional exploratory meta‐analysis (3 studies; N = 257) indicated that intrusive memories were experienced more frequently by those with posttraumatic stress disorder than those with depression. Overall, the findings suggest that intrusive memories warrant clinical attention as they may contribute to the maintenance of depressive symptomatology.  相似文献   

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Imported dengue cases are thought to be important source for transmission of autochthonous dengue in Europe. We aimed to investigate the prevalence of dengue in Europe, its severity, and factors associated with it. Out of 5287 reports resulting from the search of nine electronic search engines, we included 174 reports. Meta‐analysis was performed by pooling the event rate and 95% confidence interval (CI). Subgroup meta‐analyses were performed to test the effect of the covariates. Among 20 284 reported cases, 130 autochthonous dengue cases were reported in eight countries with the highest number of cases reported in Israel (n = 41). The highest number of imported dengue cases was in Germany (n = 6638) then France (n = 6610). Most cases were imported from Southeast Asia (n = 2533) especially Thailand. Dengue infection cases increased with time, with 4157 cases reported in 2010. Second dengue infection and dengue serotype 2 were positively associated with dengue severity. The proportion of autochthonous dengue infection increased with time to reach 14.8% (95% CI, 7.6‐26.9) in 2015. The pooled proportion of severe dengue was 6.18% (95% CI, 2.7‐13.3). The United Kingdom and France had the highest rate of severe dengue (25%; 95% CI, 6.3‐62.3, and 21.4%; 95% CI, 24.5‐18.7, respectively). This change may be due to the surveillance efforts instead of true biological phenomenon; thus, the lack of surveillance is an obvious limitation. In conclusion, imported and autochthonous dengue has been increasing in Europe. Severe dengue began to increase recently in Europe. European health authorities should pay more attention for the diagnosis and control of dengue infection among returning travelers, especially the travelers with fever of unknown origin.  相似文献   

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This study examined the electrophysiological bases of the effect of language on color perception. In a visual search task, a target was presented to the left or right visual field. The target color was either from the same category as a set of distractors (within-category condition) or from a different category (between-category condition). For both category conditions, the targets elicited a clear N2pc (N2-posterior-contralateral) component in the event-related potential (ERP) in the contralateral hemisphere. In the left hemisphere only, the N2pc amplitude for the between-category condition was larger than that for the within-category condition. These results indicate that the N2pc could be used as an index to describe the lateralization effect of language on color perception.  相似文献   

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Objective

Rational emotive behavior therapy (REBT), introduced by Albert Ellis in the late 1950s, is one of the main pillars of cognitive‐behavioral therapy. Existing reviews on REBT are overdue by 10 years or more. We aimed to summarize the effectiveness and efficacy of REBT since its beginnings and investigate the alleged mechanisms of change.

Method

Systematic search identified 84 articles, out of which 68 provided data for between‐group analyses and 39 for within‐group analyses.

Results

We found a medium effect size of REBT compared to other interventions on outcomes (d = 0.58) and on irrational beliefs (d = 0.70), at posttest. For the within‐group analyses, we obtained medium effects for both outcomes (d = 0.56) and irrational beliefs (d = 0.61). Several significant moderators emerged.

Conclusion

REBT is a sound psychological intervention. Directions for future studies are outlined, stemming from the limitations of existing ones.
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