International Journal of Health Sciences and Research www.ijhsr.org ISSN: 2249-9571 Review Article Neurobiology of Language Development: An Update Vikas Kumar1, Joydeep Das2, Madhumita Bhattacharya3 1Clinical Psychologist, Sri Sri University, Cuttack, Odisha. 2PhD. Scholar, Dept. of Clinical Psychology, Central Institute of Psychiatry, Kanke, Ranchi, Jharkhand. 3Assistant Professor, Dept. of Clinical Psychology, Central Institute of Psychiatry, Kanke, Ranchi, Jharkhand. Corresponding Author: Vikas Kumar ABSTRACT Language is a human‟s ability to use an extremely rich set of symbols, plus rule for combining them to communicate information. The concept of the emerging field of neurobiology of language is that foremost study of the human brain, i.e., it is a subfield of neuroscience and particular in human neuroscience. By saying this, we mean to distinguish this from this related field psychology and linguistics, in which the emphases of investigation are certainly to understanding the brain but are not ispo facto focused on the understanding of neural mechanism. The human brain has multiple anatomical specializations that may be relevant to explaining our capacity for language. First, human brains have wider cortical minicolumns in both Broca‟s and Wernicke‟s areas compared with great apes. Second, human brains exhibit leftward asymmetries in Broca‟s area volume and in the width of planum temporal minicolumns that are not found in great apes. Third, the projections of the human arcuate fasciculus reach beyond Wernicke‟s area to a region of expanded association cortex in the middle and inferior temporal cortex that appears to be involved in processing word meaning. Keywords: Language Development, Neurobiology of Language, Broca’s areas, Wernicke’s areas, and psychiatric disorders. INTRODUCTION The language evolution of human What is language: Language is human‟s being is thus one of the most interesting and ability to use an extremely rich set of significant evolutionary events that which symbols, plus rule for combining them to has occurred in the last 5–10 million years, communicate information. The human and indeed during the entire history of life ability to use language far exceeds that any on Earth. Given its central role in human other organism on earth. As Bhartrihari, an behavior, and in human culture, it is Indian thinker observed „Everything is unsurprising that the origin of language has cognized through language‟. Indeed, been a topic of myth and speculation since language changes the world of experience in before the beginning of history. From the critical ways. Language is a unique power dawn of modern evolutionary theory, of bestowed human to represent and share Darwin questions about the evolution of unbounded thoughts is critical to all human language have generated a rapidly growing societies and has significantly played a scientific literature. Since the 1960s, an pivotal role in the rise of human as species increasing number of scholars with in the last million years from peripheral and backgrounds in genetics, anthropology, a minor member of the sub-Saharan African speech science linguistics, neuroscience, ecological community to the dominant and evolutionary biology and devoted species on the earth today. International Journal of Health Sciences & Research (www.ijhsr.org) 256 Vol.9; Issue: 1; January 2019 Vikas Kumar et.al. Neurobiology of Language Development: An Update themselves to understand various aspects of described six characteristics of language: language evolution and language sciences. The signals used are 1) vocal; 2) articulate, Language from Apes to Humans: that is complex sounds are constructed from Mutation of the FOXP2 gene need phonetic units; 3) have a conventional not have been the only factor in the switch. meaning (to the speaker and recipient); 4) Until the emergence of Homo sapiens, the the sounds are indicative (or represent anatomical requirements for fully articulate objects or events in the environment); 5) speech were probably not complete. For they are produced with the intention of example, the hypoglossal canal is much communicating to someone else; and 6) they larger in humans than in great apes, are joined together to form new suggesting that the hypoglossal nerve, combinations. Bierens de Haan concluded which innervates the tongue, is also much that although animals meet the first five larger in humans, perhaps reflecting the criteria: “real creative language, the faculty importance of tongued gestures in speech of combining words into phrases, is beyond (Corballis, M. C., 2009). The evidence the faculties of the animal mind. It is only suggests that the size of the hypoglossal the human mind that possesses the full canal in early australopithecines, and faculty of combining words into phrases and perhaps in Homo habilis, was within the phrases into conversations, of constantly range of that in modern great apes, while creating new means to express and that of the Neandertal and early Homo communicate feelings and thought sapiens skulls was contained well within the (Snowdon, C. T., 1990). modern human range. A further clue comes The accomplishments of apes, from the finding that the thoracic region of monkeys, and birds do not approach those the spinal cord is relatively larger in humans of a human child. However, it would be than in nonhuman primates, probably naive to expect an ape to match totally the because breathing during speech involves linguistic competence of a human child. extra muscles of the thorax and abdomen Bonobos, chimpanzees, and humans are (Corballis, 2009). distinct species, each of which has evolved Animals models for language: its own communicative and cognitive Human beings are unique in that adaptations. Among the defining they communicate through a system of characteristics of our own species are our language. Non-human animals have a linguistic and cognitive skills. If we were to system of communication but lack language. find a Kanzi that imitated all human Thus, a nonhuman animal might be able to cognitive and linguistic abilities, we would signal food or danger or make sexual probably be asking ourselves what sort of advances to another animal but is not able to genetic disorder led him to be so short and produce language akin to ours. However, hairy. The finding of some rudiments of many species share with us mechanisms for language-like phenomena in natural sound production. Zebra finches share many communication, such as simple grammars, features with human beings pertaining to rudimentary symbolization, similar communication and sound production. Both perceptual systems, along with the potential have critical periods during development exhibited by some of the great apes, during which they must hear the sounds of indicates that many of the components of their respective communication or language linguistic ability have appeared at different they are to produce, and both have specific times in evolution; but it is only with human temporal periods during which they must beings that all of the components that define hear as well as practice these sounds our linguistic abilities have come together in (Helekar et. al., 2003). one species. Bierens de Haan, one of the earliest reviews of animal language parallels, International Journal of Health Sciences & Research (www.ijhsr.org) 257 Vol.9; Issue: 1; January 2019 Vikas Kumar et.al. Neurobiology of Language Development: An Update Prenatal language learning: Phonology provides a basis for Prenatal language learning is an constructing a large and expandable set important aspect of human development. of words out of two or three dozen During the third trimester of gestation, a phonemes. A phoneme is the basic unit baby in the womb can hear the mother's of sound in a language; it is the smallest voice clearly and makes use of this ability unit of sound that affects meaning. by learning the rhythms, tones, and Morphology refers to the units of sequences of whatever languages the mother meaning involved in word formation. A speaks. These phonological patterns do not morpheme is a minimal unit of meaning; stand apart from context but instead, are it is a word or a part of a word that experienced as integral parts of the mother's cannot be broken into smaller moods and activities. By building up neural meaningful parts. patterns in the brain, the baby gets a head Syntax involves the way words are start on the phonological contours, combined to form acceptable phrases grammars, and uses of the mother's and sentences. languages (Childs, M. R., 1998). Semantics refers to the meaning of Babies begin learning the language words and sentences. Every word has a in the womb. An early discovery using set of semantic features, which are acoustic spectrography revealed that the required attributes related to meaning. first cry of a 900-gram baby already Words have semantic restrictions on contained intonations, rhythms, and other how they can be used in sentences. speech features that could be matched with Pragmatics system of using appropriate the mother's voice spectrograph. This conversation and knowledge of how to proved that by about 26 weeks of gestation, effectively use language in context. this baby had already acquired certain features of its mother tongue (Sherr, L., Neurobiological origins of language: 1995). Language has a long evolutionary Communication in the antenatal period: history and is closely related to the brain, Unborn babies can recognize their but what makes the human brain uniquely mum's voice from 16 weeks and dad's adapted to language is unclear. The regions from 20 weeks of the brain that are involved in language in Unborn babies respond to singing and humans have similar analogues in apes and being read to from 24 weeks. They may monkeys, and yet they do not use language. move about to show that There may also be a genetic component; They are listening, babies develop mutations in the FOXP2 gene in humans, preferences for music while in the womb the gene that prevents from constructing and they can move in rhythm to music complete sentences (Arbib, M.