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Brain imaging studies have identified two cortical areas, the parahippocampal place area (PPA) and the retrosplenial complex (RSC), that respond preferentially to the viewing of scenes. Contrary to the PPA, little is known about the functional maturation and cognitive control of the RSC. Here we used functional magnetic resonance imaging and tasks that required attention to scene (or face) images and suppression of face (or scene) images, respectively, to investigate task-dependent modulation of activity in the RSC and whole-brain functional connectivity (FC) of this area in 7–11-year-old children and young adults. We compared responsiveness of the RSC with that of the PPA. The RSC was selectively activated by scene images in both groups, albeit less than the PPA. Children modulated activity between the tasks similarly in the RSC and PPA, and to the same extent as adults in PPA, whereas adults modulated activity in the RSC less than in PPA. In children, the whole brain FC of the RSC was stronger in the Sf than Fs task between the left RSC and right fusiform gyrus. The between groups comparison suggested stronger FC in children than adults in the Sf task between the right RSC and the left inferior parietal lobule and intraparietal sulcus. Together the results suggest that the function of the RSC and the related networks undergo dynamic changes over the development from 7–11-year-old children to adulthood. 相似文献
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言语理解是听者接受外部语音输入并且获得意义的心理过程。日常交流中,听觉言语理解受多尺度节律信息的影响,常见有韵律结构节律、语境节律、和说话者身体语言节律三方面外部节律。它们改变听者在言语理解中的音素判别、词汇感知以及言语可懂度等过程。内部节律表现为大脑内神经振荡,其能够表征外部言语输入在不同时间尺度下的层级特征。外部节律性刺激与内部神经活动的神经夹带能够优化大脑对言语刺激的处理,并受到听者自上而下的认知过程的调节进一步增强目标言语的内在表征。我们认为它可能是实现内外节律相互联系并共同影响言语理解的关键机制。对内外节律及其联系机制的揭示能够为理解言语这种在多层级时间尺度上具有结构规律的复杂序列提供了一个研究窗口。 相似文献
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James W. Roberts Simon J. Bennett Timothy N. Welsh Digby Elliott Jim L. Lyons Spencer J. Hayes 《Quarterly journal of experimental psychology (2006)》2017,70(1):154-162
Cyclical upper-limb movements involuntarily deviate from a primary movement direction when the actor concurrently observes incongruent biological motion. We examined whether environmental context influences such motor interference during interpersonal observation–execution. Participants executed continuous horizontal arm movements while observing congruent horizontal or incongruent curvilinear biological movements with or without the presence of an object positioned as an obstacle or distractor. When participants were observing a curvilinear movement, an object located within the movement space became an obstacle, and, thus, the curvilinear trajectory was essential to reach into horizontal space. When acting as a distractor, or with no object, the curvilinear trajectory was no longer essential. For observing horizontal movements, objects were located at the same relative locations as in the curvilinear movement condition. We found greater involuntary movement deviation when observing curvilinear than horizontal movements. Also, there was an influence of context only when observing horizontal movements, with greater deviation exhibited in the presence of a large obstacle. These findings suggest that the influence of environmental context is underpinned by the (mis-)matching of observed and executed actions as incongruent biological motion is primarily coded via bottom-up sensorimotor processes, whilst the congruent condition incorporates surrounding environmental features to modulate the bottom-up sensorimotor processes. 相似文献
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1型糖尿病动物模型干预研究显示有效阻断口细胞自身免疫性损伤可阻止或逆转新发生的糖尿病。已完成的临床免疫调节干预研究的结果并不令人满意,目前有数百项Ⅰ、Ⅱ期临床阶段的干预试验研究在招募或进行中。早期临床试验发现长期服用T细胞抑制剂环孢素A可提高新诊断1型糖尿病的缓解率,但是由于担心其长期服用所致的肾毒性等不良反应,终止了其在1型糖尿病治疗中的进一步应用。目前针对1型糖尿病免疫调节治疗主要集中在抗原特异性(胰岛素、谷氨酸脱羧酶65)、抗原非特异性(抗淋巴细胞单克隆抗体)免疫调节治疗和促进β细胞新生等措施方面,这三大类措施的联合应用有可能实现更有效的干预效果和较低的毒副作用。目前针对1型糖尿病的三级预防临床研究的现实意义较一、二级预防研究更大,可在较短时间内、花费更少的资金和精力获得更有效的干预措施,而这些试验的成功更加有利于一、二级1型糖尿病的预防。寻找更准确的1型糖尿病发病预测和评价干预效果的方法是成功探索1型糖尿病干预手段的关键之处。 相似文献
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Riet Fonteyne Bram Vervliet Dirk Hermans Debora Vansteenwegen 《Behaviour research and therapy》2009,47(10):830-839
Panic disorder is characterized by both specific, phased fear and generalized, chronic anxiety. Standard extinction procedures are efficient in reducing specific fear. However, methods based on human conditioning research - that are capable of reducing chronic anxiety have not yet been thoroughly investigated. This study evaluates a new way of reducing chronic anxiety by signaling aversive events (or by making them more predictable). Using an experimental approach with healthy participants, specific fear and chronic anxiety were operationalized in a within-subjects fear-potentiated startle paradigm by, respectively, conditioning to a cue by presenting predictable shocks and conditioning to a context induced by unpredictable shocks. The results clearly demonstrate that context conditioning is reduced when a discrete cue is added that predicts the onset of the aversive event. The data suggest that making unpredictable events, such as for example panic attacks, predictable, may reduce the generalized and sustained anxiety that often complicates exposure treatment. 相似文献
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Practice not only affects how information is processed, but also which information is processed. The Information-Reduction
Hypothesis (i.e. Haider & Frensch, 1996) holds that — with practice — irrelevant task information (i.e. information that is
not logically needed to correctly perform the task) is discarded from processing. Recently, Gaschler and Frensch (2007) have
demonstrated that Information Reduction is not affected by the frequency with which individual task configurations are presented:
well-practiced and little-practiced irrelevant task configurations are discarded at the same point in time during practice;
Information Reduction is thus an item-general phenomenon. These findings suggest that Information Reduction is at least in
part a consequence of top-down, voluntary control. In the present research, we ask how tasks can be constructed such that
Information Reduction is avoided. Our results show that item-general Information Reduction is observed even when it leads
to severe processing costs (i.e. errors). On the whole, the present results are in line with models of skill acquisition incorporating
top-down modulation (e.g. Haider & Frensch, 2002) and are incompatible with purely data-driven accounts of skill acquisition
(e.g. Logan, 1988; Nosofski & Palmeri, 1997; Palmeri, 1997; Rickard, 2004). 相似文献
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Several hypotheses related to Newman's (e.g., Patterson & Newman, 1993) response modulation hypothesis were examined among adolescents with attention-deficit/hyperactivity disorder (ADHD; n=18) and normal controls (n=23). Consistent with predictions, youth with ADHD committed more passive avoidance errors (PAEs) than controls during the latter trials of a computerized go/no go task with mixed incentives, and this effect remained significant or marginally significant even after common variance associated with variables that covary with ADHD (i.e., IQ, oppositional-defiant/conduct disorder [ODD/CD] symptoms, anxious/depressed mood) was removed. While a moderate inverse association was observed between PAE frequency and the amount of time spent viewing response feedback following punishment, both categorical (diagnostic) and dimensional analyses of ADHD symptomatology indicated that ADHD and reflection on punishment feedback are uniquely associated with PAE commission. Findings from this study are discussed in relation to models of disinhibition applicable to youth with ADHD.
相似文献
Richard F. FarmerEmail: |
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This study explores whether the brain can discriminate degrees of semantic congruency during wakefulness and sleep. Experiment 1 was conducted during wakefulness to test degrees of congruency by means of N400 amplitude. In Experiment 2, the same paradigm was applied to a different group of participants during natural night sleep. Stimuli were 108 sentences (definitions with two attributes) with four possible degrees of congruence as ending targets. In both studies, the amplitude of N400-like effect showed modulation according to the degree of congruency. The results indicate that the brain can accomplish sentential semantic discriminations not only in wakefulness but also in sleep. 相似文献