Age-related changes in word retrieval vary by self-reported anxiety but not depression symptoms

Tip-of-the-tongue states (TOTs) are known to increase in frequency across adulthood, but there is wide variability in older adults’ TOT rates, suggesting that individual difference factors contribute to TOT incidence. We investigated the role of affect by examining the relationship between self-reported anxiety and depression symptoms and the frequency of TOTs during a laboratory task. Participants were young, middle-aged and older adults in a population-based sample of adults aged 18–87. Increased anxiety was associated with fewer TOTs for the middle-aged group but more TOTs for the older adult group. There was no relationship between anxiety and TOTs for younger adults and no relationships between depression symptoms and TOT incidence for any age group. We discuss our results in terms of attentional control theory, which provides an explanation of how age may affect the relationship between anxiety and TOTs.     

Specific effects of the Trier Social Stress Test on speech fluency in young and older adults

The notion that speech becomes less fluent during stressful speaking conditions has received little empirical test, and no research has tested this relationship in older adult participants. We analyzed speeches produced during the Trier Social Stress Test (TSST) or during a less stressful placebo (pTSST) version of the task. We measured young and older adults’ speech fillers (e.g., um), unfilled pauses (at least 1 s in duration), and other disfluencies (e.g., repetitions, repairs). Neither young nor older adult participants rated themselves as having greater stress in the TSST than pTSST condition, but behavioral effects were obtained. Participants in the TSST condition produced more mid-phrase speech fillers and unfilled pauses than participants in the pTSST condition. Young adults produced more unfilled pauses than older adults overall, and older adults produced more mid-phrase fillers than young adults. Critically, age group interacted with experimental condition, such that older speakers produced disproportionately more mid-phrase fillers than young adults in the TSST compared to the pTSST condition. In sum, the negative effects of the TSST on fluency were generally similar across age, but this specific age-related increase in mid-phrase fillers indicates that older adults’ word retrieval may have been particularly negatively affected. Findings are generally consistent with previous research and add to understanding of how factors internal to the speaker (i.e., demographic, personality, and cognitive variables) and factors external to the speaker (i.e., variables regarding the situation, context, or content of speech) combine to affect speech fluency.     

学习方法对陌生语言字形学习的影响

采用学习——测查的范式,以陌生视觉单词(韩字)为材料,考察了学习方法对陌生语言字形学习效果的影响。在学习阶段,材料分别以连续重复(集中学习)和间隔重复(分散学习)方式呈现6遍,在学习之后半小时、1天以及1个星期之后,分别进行再认记忆测查。结果发现,虽然随着测查间隔时间的增长,两种学习条件的成绩都显著降低,但是在三次测查中,分散学习的成绩都明显好于集中学习。这一结果说明在排除语音、语义等其他言语元素的干扰之后,以分散学习的方式学习新字形的效果好于集中学习。     

Word recognition in Alzheimer's disease: Effects of semantic degeneration

Impairments of word recognition in Alzheimer's disease (AD) have been less widely investigated than impairments affecting word retrieval and production. In particular, we know little about what makes individual words easier or harder for patients with AD to recognize. We used a lexical selection task in which participants were shown sets of four items, each set consisting of one word and three non‐words. The task was simply to point to the word on each trial. Forty patients with mild‐to‐moderate AD were significantly impaired on this task relative to matched controls who made very few errors. The number of patients with AD able to recognize each word correctly was predicted by the frequency, age of acquisition, and imageability of the words, but not by their length or number of orthographic neighbours. Patient Mini‐Mental State Examination and phonological fluency scores also predicted the number of words recognized. We propose that progressive degradation of central semantic representations in AD differentially affects the ability to recognize low‐imageability, low‐frequency, late‐acquired words, with the same factors affecting word recognition as affecting word retrieval.     

Learning words and learning sounds: Advances in language development

Phonological development is sometimes seen as a process of learning sounds, or forming phonological categories, and then combining sounds to build words, with the evidence taken largely from studies demonstrating ‘perceptual narrowing’ in infant speech perception over the first year of life. In contrast, studies of early word production have long provided evidence that holistic word learning may precede the formation of phonological categories. In that account, children begin by matching their existing vocal patterns to adult words, with knowledge of the phonological system emerging from the network of related word forms. Here I review evidence from production and then consider how the implicit and explicit learning mechanisms assumed by the complementary memory systems model might be understood as reconciling the two approaches.     

Activation of semantic information at the sublexical level during handwriting production: Evidence from inhibition effects of Chinese semantic radicals in the picture‐word interference paradigm

Using a non‐alphabetic language (e.g., Chinese), the present study tested a novel view that semantic information at the sublexical level should be activated during handwriting production. Over 80% of Chinese characters are phonograms, in which semantic radicals represent category information (e.g., 椅 ‘chair,’ 桃 ‘peach,’ 橙 ‘orange’ are related to plants) while phonetic radicals represent phonetic information (e.g., 狼 ‘wolf,’ 朗 ‘brightness,’ 郎 ‘male,’ are all pronounced /lang/). Under different semantic category conditions at the lexical level (semantically related in Experiment 1; semantically unrelated in Experiment 2), the orthographic relatedness and semantic relatedness of semantic radicals in the picture name and its distractor were manipulated under different SOAs (i.e., stimulus onset asynchrony, the interval between the onset of the picture and the onset of the interference word). Two questions were addressed: (1) Is it possible that semantic information could be activated in the sublexical level conditions? (2) How are semantic and orthographic information dynamically accessed in word production? Results showed that both orthographic and semantic information were activated under the present picture‐word interference paradigm, dynamically under different SOAs, which supported our view that discussions on semantic processes in the writing modality should be extended to the sublexical level. The current findings provide possibility for building new orthography‐phonology‐semantics models in writing.     

中文词汇加工中的饱和现象

长时间注视一个字或词语后,感觉这个字词变得奇怪且陌生,这种现象称为饱和现象。本研究采用快速类别/词汇匹配范式,考察中文词汇加工中的饱和现象。实验1-3发现单纯的语义或字形的重复均未能引发饱和,只有类别标签在字形和语义上的同时重复才引发饱和,表明与英文饱和相似,中文饱和发生在字形加工和语义加工的联结阶段。实验4结果表明,中文饱和还能够由表义部件的重复引发,体现了中文饱和的特殊性。     

任务与字频对汉字情绪启动反转效应的影响

本研究使用ERP技术对比了效价判断与真假字判断两种任务形式下的汉字情绪启动效应。结果发现,在效价判断任务中高频目标字出现情绪启动的反转效应,效价不一致比一致条件下反应时短,诱发了较大的P200;低频目标字出现情绪启动的一致性效应,效价一致比不一致条件下反应时短,诱发了较大的P200与N400。真假字判断任务中高频和低频目标字均出现情绪启动的一致性效应。情绪启动的反转效应依赖于刺激材料的可通达性与注意导向,启动字与目标字的反应竞争关系导致了情绪启动的反转效应。     

新词词素熟悉性影响视觉词切分线索在新词学习中的促进作用

为考察词素熟悉性是否会影响视觉词切分线索在新词学习中的作用,本研究中新词由两类假词构成：第一类假词由两个高频字（高熟悉性词素）组成,第二类假词由两个低频字（低熟悉性词素）组成。实验采用学习-测试范式,将新词镶嵌在句子中供大学生被试阅读。结果发现,相比由低熟悉性词素构成的新词,词间空格在由高熟悉词素构成的新词中起到的促进作用更大。表明在汉语阅读过程中,词素熟悉性可能作为一种线索参与词切分。     

浅谈神经干细胞在临床应用中的伦理问题

神经干细胞在治疗中枢神经系统退形性病变中发挥重要作用,但在其移植治疗中也面临着一些问题,例如伦理问题及技术问题。如何合理地引导人们正确地认识这项研究,消除对神经干细胞移植治疗的种种误解,使全社会都能客观理性地面对这一新兴医疗技术,看到这一技术的巨大应用前景是我们要继续努力的目标。