Advance planning in language production: An investigation of inter- and intraindividual differences in the production of phrases and sentences in L1 and L2

人类的言语是一项高度复杂的技能，需要大量的认知过程。当我们计划一个句子时，我们必须首先考虑我们到底想要表达什么，然后获取所选元素的语义句法和语音属性。此外，我们必须在工作记忆中保持所需话语的活跃状态，以避免言语错误，不会失去主线。对简单句子提前计划的实证研究表明，这类句子的所有成分在演讲开始前都被激活到语音水平。然而，在不同的说话人之间，与语尾成分(即对象‘书’)相关的语音效果表现出很大的差异性。这表明，一个简单句子的所有成分被提前计划的程度在不同的说话者之间可能不同，这些差异可能存在于个体间和个体内部。虽然自20世纪80年代以来，言语理解研究一直在研究言语工作记忆容量的个体差异，但尚未对言语产生过程的可比影响进行系统的检验。此外，由于不同的策略或暂时的注意力疏忽，说话人对非发音成分的语音激活也是可能的。拟议的研究项目提出了一些旨在解决这种可能的相互作用的实验。具体而言，A节将讨论文献中所记载的规划非初始话语成分的可变性在多大程度上可以通过系统地操纵一些与语言或工作记忆相关的成分来减少，或者可以通过额外的认知措施来解释。此外，B部分将调查双语说话者的L1和L2在不同复杂的话语中被激活的程度，或者这种激活是如何被调节的。总而言之，这些结果旨在使语言产生和(言语)工作记忆容量这两个研究领域更紧密地联系在一起，这两个领域迄今被相对分开对待，从而导致对人类言语产生机制的更好理解。

Human speech is a highly complex skill which requires a multitude of cognitive processes. When we plan a sentence, we first have to consider what exactly we want to express, and then access the semantic-syntactic and phonological properties of the chosen elements. Furthermore, we have to keep the required utterance active in working memory to avoid speech errors and not 'lose the thread'. Empirical studies on the advance planning of simple sentences (e.g., 'the monk reads the book') showed that all elements of such sentences are activated up to the phonological level prior to speech onset. However, the phonological effects related to utterance-final elements (i.e., the object 'the book') have demonstrated a high variability between different speakers. This suggests that the extent to which all elements of a simple sentence are planned ahead phonologically can differ between speakers, and that these differences might be located both at an inter- and intraindividual level. While speech comprehension research has investigated interindividual differences as a function of verbal working memory capacity since the 1980s, a systematic examination of a comparable influence on processes of speech production has not yet been conducted. Moreover, it is feasible that the phonological activation of non-initial elements of an utterance also varies within speakers, as a consequence of different strategies or temporary lapses of attention. The proposed research project suggests a number of experiments which aim at addressing this possible interaction. In particular, section A shall tackle to what extent the variability of planning non-initial utterance elements documented in the literature may be either reduced by the systematic manipulation of a number of linguistic or working memory-related components, or may be explained by additional cognitive measures. Furthermore, section B shall investigate in bilingual speakers to what extent both their L1 and L2 are activated in varyingly complex utterances, or how this activation might be modulated. Together, the results aim at bringing the two research fields of language production and (verbal) working memory capacity, which so far have been treated relatively separately, closer together, thus leading to a better understanding of the mechanisms underlying human speech production.