自上而下的知识与感知歧义语音时的感官输入的匹配。
On the matching of top-down knowledge with sensory input in the perception of ambiguous speech.
机构信息
Department of Linguistics, University of Konstanz, Konstanz, Germany.
出版信息
BMC Neurosci. 2010 Jun 2;11:67. doi: 10.1186/1471-2202-11-67.
BACKGROUND
How does the brain repair obliterated speech and cope with acoustically ambivalent situations? A widely discussed possibility is to use top-down information for solving the ambiguity problem. In the case of speech, this may lead to a match of bottom-up sensory input with lexical expectations resulting in resonant states which are reflected in the induced gamma-band activity (GBA).
METHODS
In the present EEG study, we compared the subject's pre-attentive GBA responses to obliterated speech segments presented after a series of correct words. The words were a minimal pair in German and differed with respect to the degree of specificity of segmental phonological information.
RESULTS
The induced GBA was larger when the expected lexical information was phonologically fully specified compared to the underspecified condition. Thus, the degree of specificity of phonological information in the mental lexicon correlates with the intensity of the matching process of bottom-up sensory input with lexical information.
CONCLUSIONS
These results together with those of a behavioural control experiment support the notion of multi-level mechanisms involved in the repair of deficient speech. The delineated alignment of pre-existing knowledge with sensory input is in accordance with recent ideas about the role of internal forward models in speech perception.
背景
大脑如何修复已消失的语音并应对声学上模棱两可的情况？一个被广泛讨论的可能性是利用自上而下的信息来解决歧义问题。在语音的情况下，这可能导致与基于感觉的输入与词汇期望相匹配，从而产生共鸣状态，这反映在诱导的伽马波段活动（GBA）中。
方法
在本 EEG 研究中，我们比较了被试对已消失的语音片段的预注意 GBA 反应，这些片段是在一系列正确的单词之后呈现的。这些单词是德语中的最小对，它们在音段语音信息的特异性程度上有所不同。
结果
当预期的词汇信息在语音上完全指定时，与不指定的条件相比，诱导的 GBA 更大。因此，心理词汇中语音信息的特异性程度与感觉输入与词汇信息匹配过程的强度相关。
结论
这些结果与行为控制实验的结果一起支持了涉及缺陷语音修复的多层次机制的概念。预先存在的知识与感觉输入的明确对齐符合最近关于内部前馈模型在语音感知中的作用的观点。
Zotero 插件