触觉—触觉单—模式和听觉—触觉交叉模式工作记忆的神经机制的研究

目的:探讨听觉-触觉交叉模式工作记忆的大脑神经活动机理。方法:训练12个正常受试者学习触觉-触觉单一模式和听觉-触觉交叉模式工作记忆任务后,利用Neuroscan EEG系统记录脑电活动,对脑电数据分析,着重考察延时过程中事件相关脑电成分(ERP)在触觉单一模式和交叉模式中的异同。我们以往交叉模式的研究表明:在工作记忆延时过程中存在着2个主要的脑电成分LPC(Late Positive Component)和LNC(Late Negative Component)。本研究中加入了新的感觉模式——听觉,并通过比较单一模式和交叉模式,以及交叉模式中匹配和不需匹配任务间脑电成分的差异,进一步证明了交叉模式工作记忆中相继的LPC和LNC所提示的神经认知功能:不同感觉模式间的信息交互,工作记忆的维持和执行。     

空白间隔对汉字知觉干扰效应的影响

采用辨认残缺汉字的方法考察空白间隔对汉字知觉干扰效应的影响。两个实验分别考察了空白间隔的长短和不同的插入位置对汉字知觉干扰效应的影响,结果发现:(1)适当长度的空白间隔(大于等于600ms)能导致干扰效应的消失;(2)该空白间隔的位置越接近递进进程最后阶段,残缺汉字的辨认成绩越好,越不容易出现干扰。实验结果支持竞争激活假说,不支持失匹配假说。     

触觉时序知觉手臂交叉效应的性别差异

本研究探讨触觉时序知觉的手臂交叉效应是否存在性别差异。通过两个实验在较短和较长的SOA条件下考察男性和女性被试在基于体觉和基于外部空间的触觉时序判断任务中的表现。结果表明,男性与女性被试在基于体觉和基于外部空间的触觉时序判断任务中均存在手臂交叉效应,SOA较短时男性被试的手臂交叉效应显著小于女性被试,但在SOA较长的条件下手臂交叉效应没有明显的性别差异。触觉时序知觉手臂交叉效应的性别差异可能与空间知觉能力和生理解剖学因素有关。     

汉字早期字形加工中的部件数效应

探讨部件数效应是否在汉字早期字形加工中存在。要求被试识别重复速示方式下的具有不同部件数的汉字字形。大学生为被试。在实验1中,发现4部件字比在通透性、笔画数、字频和像素数上匹配的2部件字更容易识别字形;在实验2中,2部件字的通透性比4部件字更好,此时没有识别成绩上的差异。上面的结果表明在字形加工中存在着部件数效应,它指部件越多越容易识别汉字字形。在讨论部分提出了一个字形加工的部分线索模型,它指被试可以根据汉字的部分线索(例如部件)识别整个汉字。     

对汉字短时记忆编码的实验研究

本文以汉字为材料,通过将显示通道由听觉转换成视觉或由视觉转换成听觉从而引起短时记忆前摄抑制释放的方法进行研究,被试由中国学生和刚学习中文的美国学生组成。结果表明:(1)视觉显示比听觉显示条件下的回忆成绩好。(2)两类被试在显示通道双向转换时都出现明显的前摄抑制释放。本文与用英文材料作类似实验的结果作比较,提出中英文短时记忆编码操作不同的看法。     

质地密度逐渐变化对触觉识别的作用

研究关于输入、本体感受和输出对表面触觉认知的影响,旨在探索运用触觉识别质地密度逐渐变化的表面时,理论关于表面粗糙度恒定的情况下,主动手指运动产生的信息不影响触觉认知的解释是否仍然成立。实验采用表面质地密度呈正态曲线式逐渐变化,组成正负两组变化方向。正方向变化为表面质点密度向中逐渐增大,与手指触摸运动的加减速方式一致;负方向变化为表面质点密度向中逐渐减小,与手指触摸运动的加减速方式相反;另外包括一个表面密度不变的平面。让被试辨别表面质地密度变化的方向,结果发现被试能够很好地判别表面质地密度变化的方向,但在判别正向变化的表面时显得更准确;当表面密度没有变化时,被试倾向于判别为正向变化。这一发现没有支持表面密度恒定的触觉认知解释模型。与常规直觉相反,研究还发现即时反馈并没有改进触觉识别,反而降低了辨别的正确率。质地密度逐渐变化的触觉识别在变化的大小、准确和自信心方面都显示了不同,但没有发现认知学习作用该触觉任务辨别的过程。基于这些发现,文章讨论了触觉质地感知和有关存在的理论解释模式。     

图形和汉字视觉认知任务中的部分线索效应

给被试呈现一幅图的不完整信息作为线索会干扰被试对图形的辨认,这是一种部分线索效应。实验一的任务是对模糊图形的辨认,在轮廓相似组图形中,部分线索的干扰作用随呈现模糊级次数的增加而更加显著,但在轮廓非相似组图形中,模糊级呈现次数为２次和３次的情况下,也表现出了显著的部分线索效应。实验二在不完整汉字识别任务中进一步考察了部分线索效应,在事先学习的条件下,形状相似字组汉字的辨认表现出了显著的部分线索效应,而意义相似字组和随机字组汉字的辨认表现出了部分线索的促进作用。在事先不学习的条件下,随机字组和形状相似字组汉字的辨认表现出了显著的部分线索效应,而意义相似字组汉字的辨认没有表现出显著的部分线索效应。本研究用激活的观点对这些结果做出了合理的解释。     

振动触觉频率信息的工作记忆容量及存储机制

工作记忆可以同时保存多个信息并且容量有限, 这一内在机制是工作记忆研究的重点问题。视觉和言语等研究领域都发现工作记忆能够存储多个信息单元, 但对振动触觉工作记忆是否能存储多个频率信息目前尚无相关研究。由于振动触觉频率刺激和视觉刺激具有不同的神经编码机制, 以及振动频率信息是通过躯体感觉产生的模拟的、单维的、参数化信息, 振动触觉工作记忆容量及其加工存储机制的研究也必不可少。首先, 本项目将采用新的实验范式, 探究不同的刺激呈现方式以及不同反应报告方式下, 振动触觉工作记忆的容量及其认知机制。其次, 本项目也将同时运用功能磁共振成像(fMRI)技术, 来阐述振动触觉工作记忆加工存储的神经机制。探究基于触觉频率信息的参数工作记忆容量及其神经机制是完善工作记忆模型的重要补充, 将有助于提高我们对工作记忆系统的理解, 并为视觉、听觉、触觉多模态感知觉信息的跨通道研究奠定基础。     

面孔和汉字双关图的反转效应

面孔认知的反转效应已经得到了很多研究的证实.本研究使用结构信息改变的面孔、汉字和双关图作为实验材料.被试在经过面孔或者汉字的启动任务之后,可以将双关图知觉为面孔或者汉字.结果显示:在对面孔的相对辨认情景中,被试对反转面孔的反应时间显著长于正立面孔,存在反转效应.在对汉字的相对辨认情景中,正立和反转汉字的反应时间没有显著差异.这一结果表明反转效应不仅和结构信息有关,面孔专家化系统自上而下的激活对面孔反转效应起到重要的作用.     

汉字习得的年龄效应:语音完整性假设的检验

采用语音匹配任务,考察汉字习得的年龄效应及其语音完整性假设的合理性。实验1首先采用整体语音匹配任务,证明了语音匹配实验范式的有效性。实验2和实验3分别采用声母匹配和韵母匹配任务,即事先呈现汉字的声母或者韵母,之后呈现汉字,要求被试判断呈现汉字的声母或者韵母是否与事先呈现的语音片段相同。结果发现,部分语音提取的任务中存在汉字习得的年龄效应,表现为早习得的汉字,无论声母和韵母的提取都比晚习得汉字声母和韵母的提取容易。研究结果不支持语音完整性假设,任意映射假设能够解释本研究的结果。     

英汉双语者二语口语产生中音韵编码过程的同化机制

本研究运用事件相关电位技术, 结合时空微态分割分析法, 考察英汉双语者二语口语产生过程中音韵编码过程的同化与顺应机制。研究中采用图词干扰即时命名任务, 比较英汉双语者的汉语产生过程中音韵编码的加工单元与汉语母语者的汉语产生过程还是与英语母语者的英语产生过程的特点类似。反应时结果发现汉汉组、英汉组与英英组都出现显著的音节效应。事件相关电位的结果发现英汉双语者的汉语产生过程中出现了音素效应, 与其英语产生过程的特点类似, 音素效应在英语和汉语的产生过程中都出现在图画呈现后的200~250 ms之间, 而汉语母语者的汉语产生过程中仅发现了音节效应, 出现在250~300 ms之间。时空微态分割分析发现英汉双语者在汉语产生的音韵编码过程与英语母语者在英语产生过程所对应的脑电微态成分相同, 仅在持续时间上存在显著差异; 其微态成分不同于汉语母语者的汉语产生过程。上述结果表明英汉双语者汉语产生的音韵编码过程与英语作为母语时的产生过程相似, 而与汉语作为母语时的产生过程不同。英汉双语者的汉语产生过程采用了母语同化机制。     

Aging and tactile temporal order

Although it is generally held that speed of processing declines with age, there have been few studies in which tactile temporal processing has been examined with older subjects. In the present study, temporal order judgments were obtained from a group of younger subjects (n = 28, mean age = 23.5 years) and a group of older subjects (n = 93, mean age = 69.8 years). The subjects judged the temporal order of two patterns presented to the same finger, four patterns presented to the same finger, and two patterns presented to different hands. Depending on the task, the average thresholds for the older subjects ranged from two to five times longer than the thresholds from the younger subjects. In absolute terms, the largest difference between the young and older subjects was seen in correctly identifying the order of four patterns, a difference of more than 500 msec. There was some support for the decline in temporal processing being due in part to a slowing in cognitive processing, and, depending on the task, in part to stimulus persistence and difficulty in pattern identification.     

不同母语类型留学生表达汉语句子的比较

以汉语句式为测试材料,研究留学生母语是否影响他们习得汉语的问题。结果发现,留学生在主动宾句、主谓谓语句/领属句、主谓谓语句（受事主语句）和“把”字句2上的成绩表现出与其母语类型相关的规律性,母语是英语的留学生与母语是日语和韩语的留学生有显著差异。与母语语法规则接近的汉语句式较易掌握,反之就较难。这一结果提示,母语语法影响留学生习得汉语语法,在初等汉语水平阶段需要按授课对象的母语类型组织教学。     

汉语句子的标记因素对外国留学生理解的影响

以不同标记程度汉语句子为材料,母语是英语、日语和韩语的留学生为被试,母语为汉语的大学生作参照,研究汉语句子的标记因素对留学生理解的影响。结果发现:(1)有标记结构规则的句子是比较难理解的;(2)受母语的影响,有时标记程度相同的汉语句子对不同母语类型的留学生难易有差异,甚至表现相反;(3)使用频率多可能会使有标记的句子理解起来比较容易。研究结果为在对外汉语教学中有针对性教学提供参考。     

Lexical processing in a non-native language: Effects of language proficiency and learning strategy

In three experiments, native Chinese speakers were asked to use their native and non-native languages to read and translate Chinese words and to name pictures. In Experiment 1, four groups of subjects with various degrees of proficiency in their second language, English, participated. In Experiments 2 and 3, subjects were first asked to learn a list of words in a new language, French, using either Chinese words or pictures as media; then they performed the reading, naming, and translation tasks. All subjects performed better in reading words than in naming pictures, when responding in Chinese. When the response was in the non-native language (English or French), high-learning subjects were equally efficient in translation and picture-naming tasks. Low-learning subjects, however, performed better in either the translation or the picture-naming task, depending on their learning strategies. These results are consistent with the idea that both proficiency in a non-native language and the strategy for acquiring the language are main determinants for the pattern of lexical processing in that language.     

母语者与二语者屈折词和派生词语素加工的差异

语素是构成词汇的最小功能单位,是能够表达独立语义的最小成分。语素加工是指基于一定的构词规则,将语素复杂词汇进一步分解为多个语素,通过加工和重组语素,建构起对整词意义的理解。有关英语语素加工的研究发现,不仅母语者和二双语者的加工模式存在很大差异,对于屈折和派生这两种英语中重要的语素复杂词汇,其加工模式也存在较大差异,本文重点讨论了英语母语者与英语二语者对屈折和派生词加工模式的差异、成因以及影响因素。最后提出了今后需要进一步研究的问题。     

Tone perception in Cantonese and Mandarin: A cross-linguistic comparison

This study investigated the effects of linguistic experience on tone perception. Both Cantonese (in Experiment 1) and Mandarin (in Experiment 2) tones, including both lexical and nonlexical tones, were presented to three groups of subjects: Cantonese, Mandarin, and English native speakers. Subjects were asked to determine whether two auditorily presented tones were the same or different. The interval between the presentation of the two tones, and the level of interference during this interval, were manipulated. Native speakers did better at discriminating tones from their own languages than the other two groups of subjects, for both lexical and nonlexical tones. Subjects did worst when they were required to count backward during the interstimulus interval. Cantonese speakers were better than both Mandarin and English speakers at discriminating Cantonese tones, and there was no difference between Mandarin and English speakers, except in one condition. Mandarin speakers did better than both Cantonese and English speakers, and Cantonese speakers did better than English speakers, at discriminating Mandarin tones. Results are discussed in terms of the effects of language background, differences between Cantonese and Mandarin tones, and the nature of encoding in short-term memory.We thank Chung, Hon Yan, for writing programs for the experiment, and Yang, MuJang, for her assistance in testing the Mandarin subjects. This research was supported by a Summer Research Grant from the Chinese University of Hong Kong.     

The effect of motion on tactile and visual temporal order judgments

Four experiments were conducted, three with tactile stimuli and one with visual stimuli, in which subjects made temporal order judgments (TOJs). The tactile stimuli were patterns that moved laterally across the fingerpads. The subject's task was to judge which finger received the pattern first. Even though the movement was irrelevant to the task, the subjects' TOJs were greatly affected by the direction of movement of the patterns. Accuracy in judging temporal order was enhanced when the patterns moved in a direction that was consistent with the temporal order of presentation--for example, when the movement on each fingerpad was from right to left and the temporally leading site of stimulation was to the right of the temporally trailing site of stimulation. When movement was inconsistent with the temporal order of presentation, accuracy was considerably reduced, often well below chance.The bias in TOJs was unaffected by training or by presenting the stimuli to fingers on opposite hands. In a fourth experiment, subjects judged the temporal order of visual stimuli that, like the tactile stimuli, moved in a direction that was either consistent or inconsistent with the TOJ. The results were similar to those obtained with tactile stimuli. It is suggested that the bias may be affected by attentional mechanisms and by apparent motion generated between the two sites on the skin.     

Assessment of stuttering in a familiar versus an unfamiliar language

The present study investigated how well individuals knowledgeable about stuttering are able to make disfluency judgments in clients who speak another language than their own. Fourteen native speakers of Brazilian Portuguese identified and judged stuttering in Dutch speakers and in Portuguese speakers. Fourteen native speakers of Dutch identified and judged stuttering in Brazilian Portuguese speakers and in Dutch speakers. It was found that judges can make similar level of judgment in a native and a foreign language, and that native and foreign judges can make similar level of judgment irrespective of native/foreign differences. It was also found, however, that the Dutch judges performed significantly better in identifying native stutterers than foreign stutterers. And for the identification of nonstutterers, both panels performed better in their native language than in the foreign language, and in their native language they both performed better than the other panel. Both the Brazilian Portuguese and the Dutch speaking panel were generally also less confident, and found identification of stuttering more difficult in the foreign language than in the native language. In addition, when asked for the characteristics that helped them identify stutterers, they provided more detail in the native language than in the foreign language. Also a number of differences were found between the two panels which may be due to differences in training or cultural background. The implications of the findings for clinical practice and for future research in this area are discussed. EDUCATIONAL OBJECTIVES: The reader will be able to: (1) describe how language influences the identification of a speech disorder such as stuttering, and (2) list, and (3) define behaviors that help to identify stuttering in a foreign language.     

Stimulus factors in the isolation-induced aggression of Bobwhite quail and Khaki Campbell ducklings

Two studies examined the relative abilities of conspecific-derived visual and tactile stimulation to modulate the occurrence of isolation-induced aggression in Bobwhite quail and Khaki Campbell ducklings. In Experiment 1, subjects were permitted visual stimulation from conspecifics but were deprived of conspecific tactile stimulation. In both species, these subjects subsequently showed significantly less aggression towards conspecifics than birds that had been deprived of both visual and tactile stimulation from conspecifics. In Experiment 2, one group of subjects was permitted conspecific tactile stimulation but was deprived of conspecific visual stimulation. Again for both species, these subjects subsequently exhibited significantly less aggressive behavior towards conspecifics than did subjects that had been both visually and tactually de-prived. In sum, the present research suggests that both tactile and visual stimulation from a conspecific are individually sufficient to reduce isolation-induced aggression in these precocial buds.