As Emperor Akihito steps down from the Chrysanthemum Throne in Japan's first abdication in 200 years,5月1日，德仁正式成为新皇帝，2019,开创了一个新纪元Reiwa(令和;"harmony").日本命名时代的传统反映了古代对语言神圣精神的信仰。言灵(言霊;"word spirit") is the idea that words have an almost magical power to alter physical reality.通过它对社会的广泛影响，including its influence on迷信andsocial etiquette,传统诗歌and现代流行歌曲,单词kotodamahas,in a way,provided proof of its own concept.
几个世纪以来，many cultures have believed in the语言的精神力量.Over time,these ideas have extended from the realm of magic and mythology to become a topic of scientific investigation—ultimately leading to the discovery that language can indeed affect the physical world,for example,by altering our physiology.
我们的身体进化来适应我们的环境，not only over millions of years but also over the days and years of an individual's life.For instance,off the coast of Thailand,there are children who can "像海豚一样看." Cultural and environmental factors have shaped how these sea nomads of the Moken tribe conduct their daily lives,允许他们以我们大多数人无法做到的方式调整他们在水下的瞳孔。
正如广泛的潜水可以改变我们的学生，运动可以改变我们的身体，so can mental activity,比如学习和使用语言，shape the physical structures of our brains.当两个神经元对一个刺激（如一个词）作出反应时，they begin to form chemical and physical pathways to each other,which are strengthened or weakened depending on how often they are co-activated.This process of "neurons that fire together,wire together" is the basis for all learning,它反映在灰质（神经元之间相互通信）和白质（连接灰质区域的脂肪束）的形成中。
大脑适应环境的能力解释我们是如何专门听母语的声音的。All infants areborn with the abilityto discriminate between the speech sounds of different languages,but eventually become tuned to the inputs they hear the most;neural pathways corresponding to native phonemes are strengthened,而与外来声音相对应的则被删减。双语者，这个“通用”声音处理窗口stays open longer因为他们暴露在更丰富的语言环境中。In other words,the inputs that our brains receive shape how we experience the world around us.
尽管多语种是规范而不是例外,the monolingual model remains the standard for studying neurocognition.Areview of over 180 studies最近发表在杂志上行为和大脑功能讨论使用多种语言所带来的挑战affect the way we perceive and respond to our surroundings,以及大脑的物理结构。
Both of these skills are critical for learning new languages,which may explain why learning a second language可以让它更容易for you to learn a third or a fourth.This is in stark contrast to older,now debunked,大脑只有一种语言的空间（就像大脑在语言之间划分了一个固定的空间，as opposed to being an active living organ with dense and interacting connections).学习新的语言变化，and even optimizes,how you use what you already have.
To illustrate,extensive exposure to multilingual speech can result in更强大的声音编码in the evolutionarily ancient brainstem,as well as increased初级听觉皮层的灰质和白质.因此，after training,even adults may find it easier toperceive foreign speech sounds,as well as模仿外国口音,compared to monolinguals.
复杂语音信号的解码只是双语大脑面临的一个挑战。当一个口头单词展开时（例如，"c-a-n-d-l-e"),both monolinguals and bilinguals need to suppress interference from similar words that come to 必威appmind (e.g.,"cat," "can," "candy").然而，除了来自同一种语言的相似词外，多语种也考虑来自他们知道的其他语言.
事实上，双语大脑总是ready to process words from all known languages— multiplying the number of so-called "linguistic competitors." Over time,bilinguals can become experts at controlling these competitors,到了哪里单语依赖的大脑区域解决语言内的竞争（例如，the anterior cingulate cortex) show less activation for bilinguals unless they need to managecompetition across languages.
就像拥有更强壮的肌肉可以让你用更少的力量举重一样，increased gray matterin classic executive control regions may make it easier for bilinguals to manage irrelevant information.Bilinguals also have白质增加in the tracts connecting frontal control areas to posterior and subcortical sensory and motor regions,which may allow them tooff-load some of the workto areas that handle more procedural activities.因为相同的神经机制可以同时用于语言和非语言任务，multilingual experience can even affect performance in contexts根本不涉及语言.
Increased gray and white matter,as well as the ability to flexibly recruit different brain regions,may help explain why bilingualism candelay the onset of dementia symptoms通过fourto六年。Fortunately,there doesn't appear to be a deadline for fortifying your brain,as learning a foreign language can still have an impact well into adulthood and after培训数量相对较短.Furthermore,changes to one area or function are likely to have cascading effects;better cognitive control可以增强听觉处理,这可能有助于进一步的语言学习和持续的神经重组。
The human capacity for language has played a critical role in the development of civilizations,知识的传播，以及我们共同塑造环境的能力。除了神话和魔法，endowing the new Japanese era with the wordReiwa可能通过影响人们的想法和选择而产生切实的结果。
而这样的外部consequences of language在整个历史中都可以观察到，we have only recently acquired tools such as fMRI,脑电图，PET,梅格，NIRS,CT and eye tracking that enable us to see how language reaches back to shape the brain itself.我们现在知道，使用多种语言的经验可以使我们的神经结构发生广泛的变化，这些变化可以在整个生命周期和各个领域中观察到：从婴儿到老年，从感觉知觉到更高的认知加工。使用和学习语言可以改变我们的生物学，从而证实了古代的直觉，语言可以，in fact,改变物理现实。