Besides acquiring one's first language(s) in infancy, learning an additional language at a later point in life is one of the most fascinating accomplishments of the human mind. It is so fascinating that it verges on the miraculous. Scientists are not usually fond of the term, however, and many a scholar has striven to identify, characterize, and quantify, if not resolve, the cognitive and neural mechanisms underlying this uniquely human ability. The study of language learning is rendered particularly challenging by the fact that the process is driven by the complex interplay of essential learner‐intrinsic and learner‐extrinsic variables. Moreover, a great deal of language learning happens outside conscious awareness, that is, without the learner relying on explicit processes involving declarative memory or metacognitive awareness. It follows that subjective and questionnaire‐based assessments provide limited insights into the cognitive adventure that represents the learning of a language.

In order to gain theoretical insights, we must thus turn to methods that go beyond the description of overt manifestations of language knowledge and “surface” indicators of performance (i.e., external manifestations of comprehension and production). This explains the spectacular expansion of the cognitive neuroscience of language over the past three decades, involving increasingly sophisticated and diversified methods, such as neuropsychological testing, reaction time experiments, computational modeling, eye‐tracking, electrodermal conductivity, electrophysiology, magnetoencephalography, positron emission tomography, functional magnetic resonance imaging, near‐infrared spectroscopy, transcranial magnetic stimulation, and transcranial direct current stimulation. The risks attached to using such sophisticated methods should not be underestimated, however, because the more sophisticated the method, the more abstract the data obtained, and the less intuitive the interpretation.

This special issue on the cognitive neuroscience of second and artificial language learning (CoNSALL) covers a range of key topics in the study of how we learn and use novel languages. Far from being monolithic, the collection of contributions covers a spectrum of questions, approaches, methods, and considerations. The seven empirical studies and three conceptual reviews deal with a variety of target populations, including child and adult learners; monolinguals, bilinguals, and multilinguals. They cover a wide range of languages, from natural ones such as Basque, Dutch, English, German, Italian, and Spanish to artificial miniature systems, and they focus on different language areas, from vocabulary to morphology and syntax. The studies employ pictures, speech, words, sentences, animations, and videos to study lexical development, the learning of syntactic features such as grammatical gender or word order, and conceptual mapping, from the early stage of learning a second or an artificial language, to full proficiency, and even attrition of the native language. The data are based on a wide range of methodologies, from questionnaires and behavioral (psycholinguistic) measures to event‐related potentials, brain stimulation, as well as structural and functional neuroimaging.

In order to help readers choose a path through the CoNSALL special issue, or perhaps identify those contributions that they will find particularly relevant, we have compiled Table 1, which conveys the diversity of approaches and methods whilst highlighting overlaps among the papers.

The diversity that characterizes this special issue is representative of research in second language acquisition and artificial language learning. It should not be seen as a weakness; on the contrary, we believe that the wide range of dimensions covered offer excellent opportunities for transfer of knowledge across research domains and cross‐disciplinary applications of methods. And this is not just a fuzzy‐warm, well‐intended, diplomatic statement. Truly interdisciplinary science does not suddenly happen just because a group of open‐minded academics have been invited to exchange ideas and interact in a given venue for a day or two. A process of discovery and gradual adaptation is required, which entails not only the consideration of questions slightly different from our own, but also what the issues are that critically matter to researchers in neighboring fields, as well as an understanding of how other methods can shed light on the questions we have. Toward the end of this introduction we propose ways in which the different studies, reviews, and opinions presented in the special issue can be related to one another to further our understanding of language learning and use in the future, and how we see them offering interesting opportunities for novel research endeavors and cross‐fertilization.

除了在婴儿期学习第一门语言外，在生活的晚些时候学习另一门语言是人类心灵上最迷人的成就之一。它是如此迷人，以至于奇迹般的出现。但是，科学家通常不喜欢该术语，而且许多学者都在努力确定，表征和量化（如果不能解决的话）这种独特的人类能力所基于的认知和神经机制。由于学习过程是由本质上的学习者-内在变量和学习者-外在变量之间的复杂相互作用驱动的，这使得语言学习的研究变得特别具有挑战性。此外，大量的语言学习发生在意识意识之外，也就是说，学习者无需依赖涉及陈述性记忆或元认知意识的显式过程。

为了获得理论上的见识，我们因此必须转向超出对语言知识的明显表现和表现的“表面”指示（即理解和生产的外部表现）的描述的方法。这解释了过去三十年来语言认知神经科学的惊人发展，涉及越来越复杂和多样化的方法，例如神经心理学测试，反应时间实验，计算模型，眼动追踪，皮肤电导率，电生理学，磁脑电图，正电子发射断层扫描，功能磁共振成像，近红外光谱，经颅磁刺激和经颅直流电刺激。不应低估使用这种复杂方法所带来的风险，

关于第二语言和人工语言学习（CoNSALL）的认知神经科学的特刊涵盖了关于我们如何学习和使用新型语言的研究中的一系列关键主题。收集的内容绝非单一，而是涵盖了一系列问题，方法，方法和注意事项。七项实证研究和三项概念性综述涉及各种目标人群，包括儿童和成人学习者；单语，双语和多语。它们涵盖多种语言，从巴斯克语，荷兰语，英语，德语，意大利语和西班牙语等自然语言到人工微型系统，它们专注于从词汇到形态和语法的不同语言领域。这些研究使用图片，语音，单词，句子，动画和视频来研究词汇发展，从学习第二种语言或人工语言的早期到完全熟练甚至母语的损耗，学习语法特征（例如语法性别或单词顺序）和概念映射。数据基于各种方法，从问卷调查和行为（心理语言学）措施到事件相关电位，脑部刺激以及结构和功能性神经影像学。

为了帮助读者选择CoNSALL特刊的路径，或者确定他们会发现特别相关的贡献，我们编制了表1，该表传达了方法和方法的多样性，同时强调了论文之间的重叠之处。

体现这一特殊问题的多样性代表了第二语言习得和人工语言学习方面的研究。它不应被视为弱点；相反，我们认为涵盖的范围广泛，为跨研究领域的知识转移和方法的跨学科应用提供了极好的机会。这不仅是模糊，善意的外交声明。真正的跨学科科学不会突然发生，仅仅是因为邀请了一群思想开阔的学者来交流思想并在给定的场所互动一两天。需要发现和逐步适应的过程，这不仅需要考虑与我们自己的问题略有不同的问题，而且还有哪些问题对邻近领域的研究人员至关重要，以及对其他方法如何能够阐明我们所遇到的问题的理解。在本导论的结尾，我们提出了一种方法，可以使特刊中提出的不同研究，评论和意见彼此联系起来，以加深我们对未来语言学习和使用的理解，以及我们如何看待它们提供有趣的内容创新研究和交叉受精的机会。