The Role of Angular Gyrus in Prediction, Production and Comprehension

这个博士该项目将通过测试我们如何将对传入信息的内部预测与感官输入进行比较，以及为什么这对学习和健康的语言产生至关重要，从而产生一种新颖的、基于神经的理论，来解释我们如何理解周围的世界。以前的研究表明，角回（AG），大脑的一部分，只有在猿和人类中发现，可能在这个意义的过程中发挥关键作用，在不同的领域和任务。然而，它在意义形成中的具体作用仍然难以捉摸。这是一个问题，无论是发展准确的理论预测机制，以及识别时，意义的形成困难背后的认知障碍。最近的跨域合成提出，AG将反映多感官时空扩展表示的在线动态缓冲区。虽然这一假设与一些证据相一致，但这种缓冲机制的性质尚未得到充分说明，其适应性益处（即，由在线动态缓冲器的开发带来的行为优势）是未知的。更有问题的是，缺乏“AG缓冲区”的有力证据，可能是因为大多数研究没有采用能够捕获与刺激缓冲（毫秒时间尺度）相关的神经活动的建立的高时间分辨率技术。在这方面，该项目有四个目标。这个博士的第一个目标（A1）。该项目是检查时间过程中的AG的反应，使用脑电图（EEG）和测试的假设，而不是缓冲功能，AG反映了一个域一般的“意义作出枢纽”，在外部（感觉）和内部（预测）输入进行比较，预测误差计算，并相应地更新正在进行的表示。第二个目标（A2）是确定所提出的“AG意义生成中枢”的自适应益处是否与学习有关。第三个目标（A3）是确定“AG意义生成中枢”的功能是否依赖于语言产生系统。第四个目标（A4）是确定口吃是否可能取决于低效的AG对内部（发音规划）和外部（感官反馈）输入的整合。因为口吃（发展性口吃）的成年人在句子理解中的预测效率较低。这可能是因为AG功能受损和/或AG与额下回（预测的关键区域）之间的断开。因此，本研究将利用扩散张量成像（DTI）获取健康成年人和口吃成年人的扩散数据，以探讨发育性口吃是否与AG预测相关功能受损有关。

This Ph.D. project will lead to a novel, neurally-grounded theory of how we make sense of the world around us, by testing how we compare internal predictions about incoming information with sensory inputs, and why this is crucial for learning as well as for healthy language production. Previous research suggests that the angular gyrus (AG), a part of the brain found only in apes and humans, may play a key role in this sense-making process, across different domains and tasks. Yet, its specific role in sense-making remains elusive. This is an issue both for developing accurate theories of prediction mechanisms as well as for identifying when sense-making difficulties are behind cognitive impairments. A recent cross-domain synthesis has proposed that AG would reflect an online dynamic buffer of multi-sensory spatiotemporally extended representations. Whilst this hypothesis aligns with some evidence, the nature of this buffering mechanism is underspecified and its adaptive benefits (i.e., behavioural advantages brought by the development of an online dynamic buffer) are unknown. More problematic, strong evidence for the 'AG buffer' is lacking, likely because most studies did not employ high-temporal resolution techniques able to capture the building-up of neural activity associated with stimulus-buffering (millisecond time scale). In this context, there are 4 aims of this project. The first aim (A1) of this Ph.D. project is to examine the time course of AG's responses using electroencephalography (EEG) and test the hypothesis that, rather than a buffering function, AG reflects a domain-general 'sense-making hub', where external (sensory) and internal (predictions) inputs are compared, the prediction error calculated, and the ongoing representation updated accordingly. The second aim (A2) is to establish if the adaptive benefit of the proposed 'AG sense-making hub' is related to learning. The third aim (A3) is to establish whether the functioning of the 'AG sense-making hub' depends on the language production system. The fourth aim (A4) is to establish whether stuttering might depend on inefficient AG's integration of internal (articulatory planning) and external (sensory feedback) inputs. Because adults who stutter (developmental stuttering) are less efficient in prediction-making during sentence comprehension. This might be because of impaired AG functioning and/or disconnection between the AG and the inferior frontal gyrus, a key region for predictions. Therefore, this project will acquire diffusion data of both healthy adults and adults who stutter using Diffusion Tensor Imaging (DTI) to explore whether developmental stuttering relates to impairment of the AG's prediction-related function.