semantics

语义
  • 文章类型: Journal Article
    患者门户信息通常涉及特定的临床现象(例如,正在接受乳腺癌治疗的患者)和,因此,越来越受到生物医学研究的重视。这些消息需要自然语言处理,而单词嵌入模型,如word2vec,有可能从文本中提取有意义的信号,它们不适用于患者门户消息。这是因为嵌入模型通常需要数百万个训练样本来充分表示语义,而与特定临床现象相关的患者入口信息的量通常相对较小。我们介绍了一种对word2vec模型的新颖改编,PK-word2vec(其中PK代表先验知识),用于小规模的消息。PK-word2vec包含了医学词汇最相似的术语(包括问题,治疗,和测试)以及来自两个预训练嵌入模型的非医学单词作为先验知识,以改善训练过程。我们将PK-word2vec应用于2004年12月至2017年11月在范德比尔特大学医学中心电子健康记录系统中发送的患者门户消息的案例研究。我们通过一组1000个任务来评估模型,每个单词的相关性与一组由PK-word2vec生成的五个最相似的单词和一组由标准word2vec模型生成的五个最相似的单词进行比较。我们招募了200名亚马逊土耳其机械(AMT)工人和7名医学生来执行任务。该数据集由1389个患者记录组成,包括137,554条消息和10,683个独特单词。已有7981个非医学单词和1116个医学单词的先验知识。在90%以上的任务中,两位审稿人均表示,PK-word2vec比标准word2vec生成的相似词更多(p=0.01).对于两组审阅者之间的任务选择的所有比较,AMT工作者与医学生的评估差异都可以忽略不计(配对t检验下p=0.774)。PK-word2vec可以从小型消息语料库中有效地学习单词表示,标志着在处理患者门户消息方面的显著进步。
    Patient portal messages often relate to specific clinical phenomena (e.g., patients undergoing treatment for breast cancer) and, as a result, have received increasing attention in biomedical research. These messages require natural language processing and, while word embedding models, such as word2vec, have the potential to extract meaningful signals from text, they are not readily applicable to patient portal messages. This is because embedding models typically require millions of training samples to sufficiently represent semantics, while the volume of patient portal messages associated with a particular clinical phenomenon is often relatively small. We introduce a novel adaptation of the word2vec model, PK-word2vec (where PK stands for prior knowledge), for small-scale messages. PK-word2vec incorporates the most similar terms for medical words (including problems, treatments, and tests) and non-medical words from two pre-trained embedding models as prior knowledge to improve the training process. We applied PK-word2vec in a case study of patient portal messages in the Vanderbilt University Medical Center electric health record system sent by patients diagnosed with breast cancer from December 2004 to November 2017. We evaluated the model through a set of 1000 tasks, each of which compared the relevance of a given word to a group of the five most similar words generated by PK-word2vec and a group of the five most similar words generated by the standard word2vec model. We recruited 200 Amazon Mechanical Turk (AMT) workers and 7 medical students to perform the tasks. The dataset was composed of 1389 patient records and included 137,554 messages with 10,683 unique words. Prior knowledge was available for 7981 non-medical and 1116 medical words. In over 90% of the tasks, both reviewers indicated PK-word2vec generated more similar words than standard word2vec (p = 0.01).The difference in the evaluation by AMT workers versus medical students was negligible for all comparisons of tasks\' choices between the two groups of reviewers ( p = 0.774 under a paired t-test). PK-word2vec can effectively learn word representations from a small message corpus, marking a significant advancement in processing patient portal messages.
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  • 文章类型: Journal Article
    在日常生活中,人们需要对许多类型的情绪刺激做出适当的反应。这里,我们研究了人类枕部-颞叶皮层(OTC)是否显示了视觉刺激的语义类别和情感内容的共同表示。我们还探讨了语义和情感特征的OTC转换是否可以提取具有指导行为价值的信息。参与者观看了1620张情绪自然图像,同时获取了功能磁共振成像数据。使用逐体素建模,我们展示了跨OTC对语义和情感图像特征的广泛调整。对编码刺激动画的图像特征的OTC体素响应的前三个主要成分,刺激唤醒和动物与刺激效价和唤醒的相互作用。在低到中等维度,OTC调整模式比直接基于图像特征的回归变量更好地预测与每个图像相关的行为响应。这与OTC以适合引导行为的方式表示刺激语义类别和情感内容是一致的。
    In everyday life, people need to respond appropriately to many types of emotional stimuli. Here, we investigate whether human occipital-temporal cortex (OTC) shows co-representation of the semantic category and affective content of visual stimuli. We also explore whether OTC transformation of semantic and affective features extracts information of value for guiding behavior. Participants viewed 1620 emotional natural images while functional magnetic resonance imaging data were acquired. Using voxel-wise modeling we show widespread tuning to semantic and affective image features across OTC. The top three principal components underlying OTC voxel-wise responses to image features encoded stimulus animacy, stimulus arousal and interactions of animacy with stimulus valence and arousal. At low to moderate dimensionality, OTC tuning patterns predicted behavioral responses linked to each image better than regressors directly based on image features. This is consistent with OTC representing stimulus semantic category and affective content in a manner suited to guiding behavior.
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  • 文章类型: Journal Article
    发展性语言障碍(DLD)已被解释为由于抽象的代表性缺陷而产生的缺陷,或者由于在获取和协调指导学习的多种相互作用线索方面的困难而出现的缺陷。在对欧洲语言进行测试时,这些相互竞争的解释通常很难在两者之间做出决定。本文报道了在有和没有DLD的广东话儿童中产生相对条款(RC)的实验研究,这使我们能够检验从一个突出的理论-紧急主义中得出的多种发展预测。将患有DLD的儿童(N=22;6岁;6-9岁;7)与年龄匹配的典型发育同龄人(N=23)和语言匹配的儿童进行比较,执行句子重复任务的典型发育儿童(N=21;4岁;7-7岁;6)。结果表明,跨多个RC类型的儿童生产受结构频率的影响,一般语义复杂性,和成分的线性顺序,DLD组的表现比年龄匹配和语言匹配的同龄人差。结果与DLD的紧急解释一致。
    Developmental Language Disorder (DLD) has been explained as either a deficit deriving from an abstract representational deficit or as emerging from difficulties in acquiring and coordinating multiple interacting cues guiding learning. These competing explanations are often difficult to decide between when tested on European languages. This paper reports an experimental study of relative clause (RC) production in Cantonese-speaking children with and without DLD, which enabled us to test multiple developmental predictions derived from one prominent theory - emergentism. Children with DLD (N = 22; aged 6;6-9;7) were compared with age-matched typically-developing peers (N = 23) and language-matched, typically-developing children (N = 21; aged 4;7-7;6) on a sentence repetition task. Results showed that children\'s production across multiple RC types was influenced by structural frequency, general semantic complexity, and the linear order of constituents, with the DLD group performing worse than their age-matched and language-matched peers. The results are consistent with the emergentist explanation of DLD.
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  • 文章类型: Journal Article
    尽管先前的研究发现,在情感韵律感知方面,母语使用者优于非母语使用者,语义对情绪韵律感知的影响尚不清楚。本研究调查了语义学对母语和非母语的汉语单词和句子中情感韵律感知的影响。关键的操纵是韵律的一致性(积极的,否定)和语义(肯定,负,和中性)价。参与者听了一系列音频片段,并判断每个话语的情绪韵律是积极的还是消极的。结果揭示了IGA效应:母语人士比非母语人士在汉语单词和句子中更准确,更快地感知情感韵律。此外,在汉语单词中观察到语义一致性效应,在语义-韵律一致的情况下,母语和非母语的人都比在不一致的情况下更准确地识别情感韵律。然而,在汉语句子中,这种一致性效应只存在于非母语人士。此外,情绪韵律感知的IGA效应和语义一致性效应受韵律效价的影响。这些发现阐明了语义学在情感韵律感知中的作用,强调母语人士和非母语人士之间的感知差异。
    While previous research has found an in-group advantage (IGA) favouring native speakers in emotional prosody perception over non-native speakers, the effects of semantics on emotional prosody perception remain unclear. This study investigated the effects of semantics on emotional prosody perception in Chinese words and sentences for native and non-native Chinese speakers. The critical manipulation was the congruence of prosodic (positive, negative) and semantic (positive, negative, and neutral) valence. Participants listened to a series of audio clips and judged whether the emotional prosody was positive or negative for each utterance. The results revealed an IGA effect: native speakers perceived emotional prosody more accurately and quickly than non-native speakers in Chinese words and sentences. Furthermore, a semantic congruence effect was observed in Chinese words, where both native and non-native speakers recognised emotional prosody more accurately in the semantic-prosody congruent condition than in the incongruent condition. However, in Chinese sentences, this congruence effect was only present for non-native speakers. Additionally, the IGA effect and semantic congruence effect on emotional prosody perception were influenced by prosody valence. These findings illuminate the role of semantics in emotional prosody perception, highlighting perceptual differences between native and non-native Chinese speakers.
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  • 文章类型: Journal Article
    对失语症中命名错误模式的探索提供了对命名性能基础的认知过程的见解。我们调查了语义和语音能力如何相关,以及它们如何影响失语症中的命名表现。数据来自296名失语症患者,来自莫斯失语症心理语言学项目数据库,使用结构方程模型进行了分析。该模型结合了语义和语音的潜在变量以及用于命名准确性和错误模式的清单变量。在控制总体失语症严重程度后,语义和语音之间存在中度正相关。语义和语音能力都会影响命名准确性。语义能力与语义负相关,混合,无关的错误,没有回应。有趣的是,语音对语义错误有积极影响。此外,语音能力与每个语音和新词错误都呈负相关。这些结果强调了语义和语音技能在失语症中命名表现中的作用,并揭示了这些认知过程之间的关系。
    The exploration of naming error patterns in aphasia provides insights into the cognitive processes underlying naming performance. We investigated how semantic and phonological abilities correlate and how they influence naming performance in aphasia. Data from 296 individuals with aphasia, drawn from the Moss Aphasia Psycholinguistics Project Database, were analyzed using a structural equation model. The model incorporated latent variables for semantics and phonology and manifest variables for naming accuracy and error patterns. There was a moderate positive correlation between semantics and phonology after controlling for overall aphasia severity. Both semantic and phonological abilities influenced naming accuracy. Semantic abilities are negatively related to semantic, mixed, unrelated errors and no responses. Interestingly, phonology positively affected semantic errors. Additionally, phonological abilities are negatively related to each of the phonological and neologism errors. These results highlight the role of semantic and phonological skills on naming performance in aphasia and reveal a relationship between these cognitive processes.
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  • 文章类型: Journal Article
    已知Alpha振荡在几种高阶认知功能中起着核心作用,特别是选择性的注意,工作记忆,语义记忆,和创造性思维。尽管如此,我们仍然对alpha在更远程语义关联生成中的作用知之甚少,这是创造性和语义认知的关键。此外,目前还不清楚这些振荡是如何通过“创造性”的意图来塑造的,“在大多数创造性任务中都是如此。我们旨在在两个实验中解决这些差距。在实验1中,我们比较了阿尔法振荡活动(使用一种将真正的振荡活动与瞬态事件区分开的方法)离一个给定的概念不那么遥远。在实验2中,我们复制了这些发现,并比较了人们产生自由关联时的alpha振荡活动与具有创造性(即目标导向)的指令的关联。我们发现,在更远的语义关联的产生过程中,alpha始终更高,在两个实验中。这种影响很普遍,涉及左右半球的区域。重要的是,创造性的指令似乎增加了从左到右颞脑区域的α相位同步,这表明创造性的意图改变了大脑中信息的流动,可能反映了对语义搜索过程的自上而下控制的增加。我们得出的结论是,与自由生成关联时相比,以目标为导向的远程关联生成依赖于自上而下的机制。
    Alpha oscillations are known to play a central role in several higher-order cognitive functions, especially selective attention, working memory, semantic memory, and creative thinking. Nonetheless, we still know very little about the role of alpha in the generation of more remote semantic associations, which is key to creative and semantic cognition. Furthermore, it remains unclear how these oscillations are shaped by the intention to \"be creative,\" which is the case in most creativity tasks. We aimed to address these gaps in two experiments. In Experiment 1, we compared alpha oscillatory activity (using a method which distinguishes genuine oscillatory activity from transient events) during the generation of free associations which were more vs. less distant from a given concept. In Experiment 2, we replicated these findings and also compared alpha oscillatory activity when people were generating free associations versus associations with the instruction to be creative (i.e. goal-directed). We found that alpha was consistently higher during the generation of more distant semantic associations, in both experiments. This effect was widespread, involving areas in both left and right hemispheres. Importantly, the instruction to be creative seems to increase alpha phase synchronisation from left to right temporal brain areas, suggesting that intention to be creative changed the flux of information in the brain, likely reflecting an increase in top-down control of semantic search processes. We conclude that goal-directed generation of remote associations relies on top-down mechanisms compared to when associations are freely generated.
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  • 文章类型: Journal Article
    结直肠癌(CRC)是世界范围内常见的消化系统肿瘤,发病率和死亡率均较高。目前,使用计算机辅助结肠镜技术检测息肉相对成熟,但是它仍然面临一些挑战,如漏检或误检息肉。因此,如何更准确地提高息肉的检出率是结肠镜检查的关键。为了解决这个问题,本文提出了一种改进的基于YOLOv5的结直肠癌息肉检测方法。该方法设计了一种称为P-C3的新结构,该结构被合并到模型的主干和颈部网络中,以增强特征的表达。此外,在骨干网络的底部引入了上下文特征增强模块,以增加多尺度特征信息的感受域,并通过协调注意力机制关注息肉特征。实验结果表明,与一些传统的目标检测算法相比,本文提出的模型对息肉的检测精度有显著的优势,特别是在召回率方面,这在很大程度上解决了息肉漏检的问题。本研究将有助于提高内镜医师在结肠镜检查过程中息肉/腺瘤的检出率,对临床工作的发展也具有重要意义。
    Colorectal cancer (CRC) is a common digestive system tumor with high morbidity and mortality worldwide. At present, the use of computer-assisted colonoscopy technology to detect polyps is relatively mature, but it still faces some challenges, such as missed or false detection of polyps. Therefore, how to improve the detection rate of polyps more accurately is the key to colonoscopy. To solve this problem, this paper proposes an improved YOLOv5-based cancer polyp detection method for colorectal cancer. The method is designed with a new structure called P-C3 incorporated into the backbone and neck network of the model to enhance the expression of features. In addition, a contextual feature augmentation module was introduced to the bottom of the backbone network to increase the receptive field for multi-scale feature information and to focus on polyp features by coordinate attention mechanism. The experimental results show that compared with some traditional target detection algorithms, the model proposed in this paper has significant advantages for the detection accuracy of polyp, especially in the recall rate, which largely solves the problem of missed detection of polyps. This study will contribute to improve the polyp/adenoma detection rate of endoscopists in the process of colonoscopy, and also has important significance for the development of clinical work.
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  • 文章类型: Journal Article
    与环境中的物体交互需要确定它们的位置,通常相对于周围的物体(即,分配)。根据场景语法框架,这些通常很小,局部对象在场景中是可移动的,并且代表场景层次结构的最低级别。场景语法的更高层次如何影响内存引导动作的分配中心编码?我们专注于大的影响,不可移动的对象(锚)对本地对象位置的编码。在虚拟现实研究中,参与者(n=30)观看了四个可能的场景之一(两个厨房或两个浴室),有两个用架子连接的锚,在其上呈现三个局部对象(与一个锚一致)(编码)。场景被重新呈现(测试),其中1)局部对象缺失和2)锚之一移位(移位)或不移位(无移位)。参与者,然后,看到一个浮动的局部对象(目标),他们抓住它,并把它放在架子上记住的位置(回应)。眼球追踪数据显示,局部物体和锚点都被固定住了,首选本地对象。此外,锚引导的局部对象的分配中心编码,尽管与任务无关。总的来说,锚点隐式影响自然(虚拟)环境中内存引导动作的本地对象位置的空间编码。
    Interacting with objects in our environment requires determining their locations, often with respect to surrounding objects (i.e., allocentrically). According to the scene grammar framework, these usually small, local objects are movable within a scene and represent the lowest level of a scene\'s hierarchy. How do higher hierarchical levels of scene grammar influence allocentric coding for memory-guided actions? Here, we focused on the effect of large, immovable objects (anchors) on the encoding of local object positions. In a virtual reality study, participants (n = 30) viewed one of four possible scenes (two kitchens or two bathrooms), with two anchors connected by a shelf, onto which were presented three local objects (congruent with one anchor) (Encoding). The scene was re-presented (Test) with 1) local objects missing and 2) one of the anchors shifted (Shift) or not (No shift). Participants, then, saw a floating local object (target), which they grabbed and placed back on the shelf in its remembered position (Response). Eye-tracking data revealed that both local objects and anchors were fixated, with preference for local objects. Additionally, anchors guided allocentric coding of local objects, despite being task-irrelevant. Overall, anchors implicitly influence spatial coding of local object locations for memory-guided actions within naturalistic (virtual) environments.
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  • 文章类型: Journal Article
    人类可以快速阅读和理解文本,暗示读者可能会处理每个固定的多个单词。然而,在何种程度上,半心词被预览和整合到不断发展的句子上下文仍然存在争议。我们通过使用MEG和眼动仪记录大脑活动和眼球运动,研究了自然阅读过程中的旁凹处理,而参与者则默默地阅读一行句子。句子包含一个不可预测的目标单词,该单词与句子上下文一致或不一致。为了测量半凹加工,我们以60Hz闪烁目标单词,并测量由此产生的大脑反应(即快速隐形频率标记,RIFT)在对预目标单词的注视期间。我们的结果表明,与相同的目标单词相比,与先前上下文不一致的目标单词的标记响应显着较弱,甚至在100ms内固定的单词紧前面的目标。还发现RIFT反应的这种降低可以预测个体的阅读速度。我们得出的结论是,语义信息不仅可以从parafovea中提取,而且可以在固定单词之前与先前的上下文集成。这种早期和广泛的半凹处理支持自然阅读所需的快速文字处理。我们的研究表明,自然阅读的理论框架应纳入深的副凹加工的概念。
    Humans can read and comprehend text rapidly, implying that readers might process multiple words per fixation. However, the extent to which parafoveal words are previewed and integrated into the evolving sentence context remains disputed. We investigated parafoveal processing during natural reading by recording brain activity and eye movements using MEG and an eye tracker while participants silently read one-line sentences. The sentences contained an unpredictable target word that was either congruent or incongruent with the sentence context. To measure parafoveal processing, we flickered the target words at 60 Hz and measured the resulting brain responses (i.e. Rapid Invisible Frequency Tagging, RIFT) during fixations on the pre-target words. Our results revealed a significantly weaker tagging response for target words that were incongruent with the previous context compared to congruent ones, even within 100ms of fixating the word immediately preceding the target. This reduction in the RIFT response was also found to be predictive of individual reading speed. We conclude that semantic information is not only extracted from the parafovea but can also be integrated with the previous context before the word is fixated. This early and extensive parafoveal processing supports the rapid word processing required for natural reading. Our study suggests that theoretical frameworks of natural reading should incorporate the concept of deep parafoveal processing.
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  • 文章类型: Journal Article
    创造力的联想理论提出,创意思想是通过将记忆中远程相关的概念联系起来而产生的。先前的研究发现,创造性较高的个体表现出更灵活的语义记忆组织,产生更多不常见的单词联想,并判断远程概念更相关。在这项研究中(N=93),我们使用功能磁共振成像来研究涉及判断语义距离不同的概念的相关性的大脑区域,以及这种神经参与如何与创造力的个体差异有关。活动随着语义相关性增加的大脑区域主要与默认重叠,control,显著性,语义控制,和多个需求网络。在评估更多远程关联时,默认和语义控制网络的参与度增加。最后,更有创造力的人,平均而言,谁提供了更高的相关性判断,在这些地区表现出较低的活动,可能反映了更高的神经效率。我们在创造力的神经认知过程的背景下讨论这些发现。总的来说,我们的发现表明,判断远程概念相关反映了创造力背后的认知机制,并揭示了这种机制的神经相关性。
    The associative theory of creativity proposes that creative ideas result from connecting remotely related concepts in memory. Previous research found that higher creative individuals exhibit a more flexible organization of semantic memory, generate more uncommon word associations, and judge remote concepts as more related. In this study (N = 93), we used fMRI to investigate brain regions involved in judging the relatedness of concepts that vary in their semantic distance, and how such neural involvement relates to individual differences in creativity. Brain regions where activity increased with semantic relatedness mainly overlapped with default, control, salience, semantic control, and multiple demand networks. The default and semantic control networks exhibited increased involvement when evaluating more remote associations. Finally, higher creative people, who provided higher relatedness judgements on average, exhibited lower activity in those regions, possibly reflecting higher neural efficiency. We discuss these findings in the context of the neurocognitive processing underlying creativity. Overall, our findings indicate that judging remote concepts as related reflects a cognitive mechanism underlying creativity and shed light on the neural correlates of this mechanism.
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