Cognitive processes underlying non literal language understanding: how? When? and Where

本研究的目的是研究年轻人和老年人非字面语言理解的认知过程和神经基础。非字面语言（NL）包括隐喻、间接言语行为、讽刺、反讽和许多其他语言结构，这些语言结构显然需要理解者超越字面陈述来理解说话者的交际意图，从而理解话语的意义。关于我们如何理解自然语言，有两个核心问题。第一个问题是：话语的字面意义和国家语言意义是同时被激活的，还是其中一个被优先实现？第二个问题涉及到与NL语言处理有关的神经基质：在NL语言处理中，是否存在有利于右半球特异性的大脑不对称？鉴于这种不对称性，第三个问题随之而来：年龄是否会影响维持自然语言处理的神经网络？目前还没有研究成功地梳理出自然语言处理背后的不同过程。此外，还没有研究比较反语和隐喻的成像处理方法。最后，关于自然语言处理中涉及的神经基质尚无共识。行为方法和近红外光谱-扩散光学成像技术（NIRS-DOT）将用于本研究项目。因此，NIRS-DOT允许在理解过程中对两种现象的时间过程进行细微的时间区分，并提供足够的空间分辨率来确定右半球在NL语言处理中的可能作用。本研究项目的结果将有助于更好地理解大脑和认知机制，这些机制允许年轻人和老年人进行高水平的语言处理。

The general aim of this research program is to examine the cognitive processes and neural substrate underlying non literal language understanding in young adults and elderly adults.  Non literal (NL) language includes metaphor, indirect speech acts, sarcasm, irony and many other linguistic constructions that produce an apparent need for comprehenders to go beyond what is literally stated to apprehend the communicative intent of speakers, and, consequently the meaning of utterances. There are two central questions concerning how we comprehend NL language. The first one is: are the literal and the NL meanings of the utterance activated simultaneously or is one of them is achieved preferentially? The second question concerns the neural substrate involved in NL language processing: Is there a cerebral asymmetry in favour of a specificity of the right hemisphere (RH) in the processing of NL language? Given such asymmetry a third question follows: does age influence the neural networks sustaining NL language processing? No study has succeeded in teasing apart the different processes underlying NL language processing. Moreover, there is no study comparing irony and metaphor processing using imaging methods. Finally, there is no consensus concerning the neural substrate involved in NL language processing. Behavioural approach and Near infrared spectroscopy-Diffused optical imaging techniques (NIRS-DOT) will be used in this research program. Thus, NIRS-DOT allows subtle temporal discrimination between the time courses of either phenomena during comprehension, and provides sufficient spatial resolution to identify a possible role of the right hemisphere in NL language processing. Results of the present research program will contribute to a better understanding of the brain and cognitive mechanisms that allow high level language processing in young and elderly adults.