不同认知方式个体抑制句法歧义的加工

该研究采用自定速的移动窗口范式,考察场依存、场独立个体抑制句法歧义的差异以及句法歧义的加工机制。结果表明:不同认知方式个体在抑制句子中句法歧义的能力上存在差异,与场依存者相比,场独立者能够很好地抑制句法歧义的干扰;而且,实验结果支持句子加工的花园路径模型。     

语境位置对不同认知方式个体歧义句歧义消解的影响

采用意义适合性判断任务,考察了语境位置对不同认知方式个体歧义句理解过程中抑制内部干扰的影响。结果发现：语境位置影响歧义句的歧义消解,对歧义句不适当意义的抑制作用方面,前语境优于后语境;在自然阅读的条件下,在句子加工的初始阶段,场独立个体能够更好的利用前语境信息抑制内部无关信息的干扰,而场依存个体在句子加工的初始阶段对前、后语境的阅读时间上不存在差异,而在句子加工的后期需用更多时间才能完成对内部干扰的抑制。     

汉语同音歧义词歧义消解的过程及其抑制机制

两个实验分别采用词语境或句子语境探讨汉语同音歧义词(homophones)歧义消解的过程。被试为112名大学生。实验通过有计划地比较不同语境偏向条件下有关探测词和无关探测词之间反应时的差异,从而揭示汉语同音歧义词消解过程中,对其适当意义激活以及对其不适当意义抑制的时间进程。两个实验的结果都表明：在同音歧义词加工的早期,语境的作用主要表现为抑制歧义词不适当意义,阻止其激活;随后,语境促进了歧义词适当意义的激活。另外,相对意义频率在同音歧义词歧义消解过程中有其影响。     

汉语歧义词加工中抑制机制的作用过程

两个实验探讨对汉语同形歧义词和同音歧义词不适当意义（与句子语境不一致）抑制的时间进程。被试为128名大学生,实验采用意义适合性判断任务,即要求被试又快又准地判断探测词的意义与刚呈现的句子意义是否相符合,探测词分别在ISI（interstimulus interval）为200和800ms时呈现。实验结果表明：（1）ISI为200ms时对同形歧义词的不适当次要意义的抑制尚未完成;但是对同音歧义词的不适当次要意义的抑制基本完成。（2）ISI为800ms时对同形歧义词的不适当次要意义的抑制基本完成;（3）即使延长加工时间,同形歧义词和同音歧义词的不适当主要意义还是难以被完全抑制。     

汉语歧义句的消解过程

实验以汉语同形且切分层次相同的歧义句为实验材料,采用句子验证任务,着重探讨前语境或后语境在歧义句歧义消解过程中的作用及其时间进程,被试为48名大学生。结果发现：(1)抑制机制受语境位置的制约,前语境的抑制作用优于后语境;(2)ISI为300毫秒时,对歧义句不适当意义的抑制已经发生,但尚未完成;ISI延长到1000毫秒时,对歧义句不适当意义的抑制进一步加强。     

不同认知方式个体在语篇阅读中抑制外部干扰的眼动研究

采用眼动追踪技术探讨了当干扰材料的意义性不同和干扰材料位置可预测性不同时, 不同认知方式个体在语篇阅读中抑制外来无关干扰的特点, 结果表明: 不同认知方式个体在语篇阅读中抑制外部干扰的能力存在差异, 场独立者好于场依存者, 而且这种差异发生在抑制加工的后作用过程, 本研究支持Dywan等人提出的理论观点。不管是场依存者还是场独立者在语篇阅读中, 相对于无意义干扰材料, 有意义的外部干扰更能吸引阅读者的注意力, 对语篇阅读的干扰作用更明显; 相对于可预测位置的干扰, 读者在阅读过程中更难避开不可预测位置的干扰材料, 其产生的干扰作用更大。     

汉语同形歧义词歧义消解的过程

实验采用启动范式,利用句子语境探讨同形歧义词（homographs）歧义消解的过程。结果表明：与语境一致的歧义词的主要意义首先得到通达,与语境一致的次要意义随后才被激活,与语境不一致的歧义词的意义没有得到激活,语境敏感模型可以较好地解释本实验的结果。     

词汇歧义消解的脑机制

词汇歧义是语言歧义的一种, 词汇歧义消解受到相对意义频率和语境的影响。半视野研究发现大脑两半球都能在词汇歧义消解过程中根据语境信息选择性地激活歧义词的恰当意义、抑制不恰当意义, 其中左半球的语义选择功能更强; 脑损伤研究发现大脑左、右半球损伤都会导致词汇歧义消解中语义选择障碍, 词汇歧义消解需要大脑两半球的联合作用; 神经成像研究进一步发现额叶与颞叶共同支持词汇歧义消解, 歧义词的恰当意义的选择是由额下回执行的, 语义整合加工是由颞叶负责的。     

句子语境中汉语词汇歧义消解的眼动研究

采用眼动方法.通过两个实验考察了汉语同音同形歧义词的歧义消解过程.结果显示:(1)在中性句子语境中,均衡歧义词的首视时间显著高于偏向歧义词.歧义词的意义通达仅受歧义词意义的相对频率影响,不受语境的影响;(2)在偏向句子语境中,当语境支持歧义词的次要意义时,被试对偏向歧义词的解歧信息的注视时间显著高于其他两类目标词,体现了语境对歧义词意义的整合作用.实验结果支持词汇歧义消解的模块化模型的观点.     

外显、内隐记忆中不同认知方式个体的社会定向

以中文双字词为实验材料,分别从两个层面探讨场依存个体与场独立个体对社会词或非社会词的记忆有无偏向。实验一采用双任务,分散注意学习条件,实验二引入加工分离程序(PDP)。研究结果表明:(1)在双任务分散注意学习条件下,场依存个体对非目标社会词存在记忆偏向。(2)在内隐记忆成绩上,场依存个体对社会词存在记忆偏向,场独立个体对非社会词存在记忆偏向。     

Sensitivity to local sentence context information in lexical ambiguity resolution: evidence from left- and right-hemisphere-damaged individuals

Using a cross-modal semantic priming paradigm, the present study investigated the ability of left-hemisphere-damaged (LHD) nonfluent aphasic, right-hemisphere-damaged (RHD) and non-brain-damaged (NBD) control subjects to use local sentence context information to resolve lexically ambiguous words. Critical sentences were manipulated such that they were either unbiased, or biased toward one of two meanings of sentence-final equibiased ambiguous words. Sentence primes were presented auditorily, followed after a short (0 ms) or long (750 ms) interstimulus interval (ISI) by the presentation of a first- or second-meaning related visual target, on which subjects made a lexical decision. At the short ISI, neither patient group appeared to be influenced by context, in sharp contrast to the performance of the NBD control subjects. LHD nonfluent aphasic subjects activated both meanings of ambiguous words regardless of context, whereas RHD subjects activated only the first meaning in unbiased and second-meaning biased contexts. At the long ISI, LHD nonfluent aphasic subjects failed to show evidence of activation of either meaning, while RHD individuals activated first meanings in unbiased contexts and contextually appropriate meanings in second-meaning biased contexts. These findings suggest that both left (LH) and right hemisphere (RH) damage lead to deficits in using local contextual information to complete the process of ambiguity resolution. LH damage seems to spare initial access to word meanings, but initially impairs the ability to use context and results in a faster than normal decay of lexical activation. RH damage appears to initially disrupt access to context, resulting in an over-reliance on frequency in the activation of ambiguous word meanings.     

Prior context and the perception of lexically ambiguous sentences

The perceptual complexity of lexically ambiguous and unambiguous sentences was compared in three experiments. In Experiment 1, the report of ambiguous words from rapidly presented ambiguous sentences was worse than the report of corresponding unambiguous words from unambiguous sentences. Results of Experiment 2 showed that the effect was not reduced by the presence of prior biasing context within the sentence. Experiment 3 repeated the finding with a sentence meaning classification task. It was concluded that both meanings of a lexically ambiguous sentence must be computed, even when prior context makes one meaning more plausible than the other.     

Hemispheric contributions to lexical ambiguity resolution in a discourse context: evidence from individuals with unilateral left and right hemisphere lesions

In the present study, a cross-modal semantic priming task was used to investigate the ability of left-hemisphere-damaged (LHD) nonfluent aphasic, right-hemisphere-damaged (RHD) and non-brain-damaged (NBD) control subjects to use a discourse context to resolve lexically ambiguous words. Subjects first heard four-sentence discourse passages ending in ambiguous words and after an inter-stimulus interval (ISI) of either 0 or 750 ms, made lexical decisions on first- or second-meaning related visual targets. NBD control subjects, at the 0 ms ISI, only activated contextually appropriate meanings, though significant effects, as a group, were only seen in second-meaning biased contexts. Surprisingly, at the 750 ms ISI, these subjects activated both appropriate and inappropriate meanings in first-meaning biased contexts. With respect to the LHD nonfluent aphasic patients, the majority activated first meanings regardless of context at the 0 ms ISI, though effects for the group were not significant. At the 750 ms ISI, these patients again activated first meanings regardless of context, with significant effects for the group only seen in first-meaning biased contexts. With regard to the RHD patients, the majority activated second meanings regardless of context at the 0 ms ISI and first meanings regardless of context at the 750 ms ISI, though, as a group, the effects were not significant. In light of our previous findings (Grindrod & Baum, 2003, submitted), the present data are interpreted as supporting the notion that damage to the left hemisphere disrupts either lexical access processes or the time course of lexical activation, whereas damage to the right hemisphere impairs the use of context and leads to activation of ambiguous word meanings based on meaning frequency.     

Understanding words in sentence contexts: the time course of ambiguity resolution

Spoken language comprehension requires rapid integration of information from multiple linguistic sources. In the present study we addressed the temporal aspects of this integration process by focusing on the time course of the selection of the appropriate meaning of lexical ambiguities ("bank") in sentence contexts. Successful selection of the contextually appropriate meaning of the ambiguous word is dependent upon the rapid binding of the contextual information in the sentence to the appropriate meaning of the ambiguity. We used the N400 to identify the time course of this binding process. The N400 was measured to target words that followed three types of context sentences. In the concordant context, the sentence biased the meaning of the sentence-final ambiguous word so that it was related to the target. In the discordant context, the sentence context biased the meaning so that it was not related to the target. In the unrelated control condition, the sentences ended in an unambiguous noun that was unrelated to the target. Half of the concordant sentences biased the dominant meaning, and the other half biased the subordinate meaning of the sentence-final ambiguous words. The ISI between onset of the target word and offset of the sentence-final word of the context sentence was 100 ms in one version of the experiment, and 1250 ms in the second version. We found that (i) the lexically dominant meaning is always partly activated, independent of context, (ii) initially both dominant and subordinate meaning are (partly) activated, which suggests that contextual and lexical factors both contribute to sentence interpretation without context completely overriding lexical information, and (iii) strong lexical influences remain present for a relatively long period of time.     

Event-related potentials indicate context effect in reading ambiguous words

The aim of the study was a comparison of lexical and contextual factors in understanding ambiguous words in German. First, a sample of native speakers selected 56 words having maximally strong differences between a dominant and a subordinate meaning. After this, another sample from the same population was visually presented with sentences that activated dominant or subordinate meanings of the words and were accompanied by probes associated with dominant or subordinate meanings. This resulted in a crossed design with two factors: sentence dominant vs. sentence subordinate and probe dominant vs. probe subordinate. An analysis of event-related brain potentials revealed a large, long-lasting and highly-significant N400 wave whenever the meaning of the probe was incongruent with the meaning of the sentence and the lack of this wave whenever the two meanings were congruent. In the typical N400 space and time, the effect was independent of whether the lexical word meaning was dominant or subordinate. At other sites and times, however (e.g., at lateral frontal electrodes F7/F8, and after 700 ms), the congruence effect was significant after dominant sentences only. The data indicate that lexical factors have a rather limited influence on the activation of a particular meaning of ambiguous words. A strong context can virtually override even a very strong difference in the preference for different meanings.     

句子语境中汉语词类歧义词的意义激活

以单字词为实验材料 ,采用跨通道启动真假字判断任务 ,在句子语境中考察汉语词类歧义词不同意义激活的特点。被试为 134名北京师范大学本科学生。实验时向被试听觉呈现含有歧义词的句子 ,且句子语境分别支持歧义词的主要或次要意义 ,以不同的ISI分别呈现与歧义词两种意义有关的视觉目标词。结果发现 ,当探测目标词在最短的ISI出现时 ,与语境支持的意义有关的目标词反应时较短 ,表明语境在歧义词加工早期促进合适意义的激活 ,同时限制不合适意义的激活。实验数据支持相互作用理论     

Processing homonymy and polysemy: effects of sentential context and time-course following unilateral brain damage

The present study investigated the abilities of left-hemisphere-damaged (LHD) non-fluent aphasic, right-hemisphere-damaged (RHD), and normal control individuals to access, in sentential biasing contexts, the multiple meanings of three types of ambiguous words, namely homonyms (e.g., "punch"), metonymies (e.g., "rabbit"), and metaphors (e.g., "star"). Furthermore, the predictions of the "suppression deficit" and "coarse semantic coding" hypotheses, which have been proposed to account for RH language function/dysfunction, were tested. Using an auditory semantic priming paradigm, ambiguous words were incorporated in dominant- or subordinate-biasing sentence-primes followed after a short (100 ms) or long (1,000 ms) interstimulus interval (ISI) by dominant-meaning-related, subordinate-meaning-related or unrelated target words. For all three types of ambiguous words, both the effects of context and ISI were obvious in the performance of normal control subjects, who showed multiple meaning activation at the short ISI, but eventually, at the long ISI, contextually appropriate meaning selection. Largely similar performance was exhibited by the LHD non-fluent aphasic patients as well. In contrast, RHD patients showed limited effects of context, and no effects of the time-course of processing. In addition, although homonymous and metonymous words showed similar patterns of activation (i.e., both meanings were activated at both ISIs), RHD patients had difficulties activating the subordinate meanings of metaphors, suggesting a selective problem with figurative meanings. Although the present findings do not provide strong support for either the "coarse semantic coding" or the "suppression deficit" hypotheses, they are viewed as being more consistent with the latter, according to which RH damage leads to deficits suppressing alternative meanings of ambiguous words that become incompatible with the context.     

无语境条件下汉语词类歧义词的意义激活

以单字词为实验材料,采用启动命名任务,在孤立词条件下考察了汉语词类歧义词不同意义激活的时间进程特点。实验发现,歧义词的两种意义都能被激活,但主要意义激活得较早,次要意义激活速度较慢;当两种意义都激活之后,次要意义的激活水平降低,而主要意义仍维持在一定激活水平。结果表明,汉语词类歧义词的多重激活过程会受到意义相对频率的影响。