An interesting question concerns the role of intelligence in the acquisition of language. Is mastery of this, in a sense, highly abstract behavior dependent upon measurable intelligence? The problem is complicated (1) by the definition of intelligence and (2) by the changing intelligence quotients with chronological age among the feeble-minded. An individual whose cognitive status remains constant on a level comparable to that of the normal three-year-old appears to have a steadily falling IQ throughout childhood due to the peculiar way in which this figure is computed. The situation is well-illustrated in the scattergram of Fig7-10. (Compare also Zeaman and house,1962.)The study of the mongoloid population, as well as that of additional case of mental retardation, indicates that there is a certain “IQ threshold value” that varies with age and that must be attained for language to be acquired. Individuals below this threshold have varying degrees of language primitivity, as illustrated in Fig. 4.3(Chapter Four). It is noteworthy that this threshold is relatively low. If we take a population whose IQ is at or just above threshold, which is the case of mongoloids intelligence figures correlate quite poorly with language development. Only if we confine our observations to the low grades of feeblemindedness can a relationship between intelligence and language learning be established.
Among the mongoloids, whose prognosis for mental development is not the worst, chronological age is a much better predictor for language development than computed IQ’s.
The relationship between physical maturation and language development has been treated in Chapter Four. Relevant to the same topic is Table7.4.
( The criteria for “language developing “was the predominance of words and phrases in all utterances and absence or at most a modicum of random babbling.) The relationship between development of gait and of language appears to be roughly similar to that of normal children; there is greater likelihood for language acquisition after gait is established than before. The development of hand preference is particularly interesting. Right-handedness emerges at the time that language unfolds, even though this occurs at a considerably later time than in normal children.
Mongoloid children are known for their simple but affectionate and pleasant personalities. They are eager to please those surrounding them and, of course, are more dependent on parental care than the ordinary child. They have a tendency toward clowning, and they love to imitate. (Such generalizations are possible because they are remarkably alike in their disposition!) Because of their retardation both their state of dependency and their babbling phase are protracted often years beyond the normal duration of these periods. Considering these data, we may well wonder how the development of language differs in these children from that of the rest of the population. If dependence upon adults, extensive babbling, and propensity for imitation were sufficient factors for language development, these children should develop better language than others. Naturally, their mentation must be deemed insufficient for rapid language progress. On the other hand, some do eventually develop all the essentials of language, and, in these cases, we can hardly suppose that they eventually improve their mentation. Once more we are brought to believe that there is an immanent schedule of evolvement in which apparently one set of events sets the stage for a subsequent set, and so on. However, in the case of mongoloids, where worried parents make often desperate efforts to teach their child to speak, where bodily imitation is frequently specifically rewarded by those tending to the child’s needs, we might expect that the children differ among themselves and from other children in “their strategies” for language acquisition. Would it not be possible, theoretically, that one child first tried to perfect his articulation before trying to increase his vocabulary; another might always try to make sentences out of the ten words he knows; or still another might have all his needs taken care of by his family and therefore content himself with learning to understand language without making an effort to speak himself.
Our investigation have shown that this is not so. In all the patients studied, the sequence of learning phases and the synchrony of emergence of different language aspects remained undisturbed by the disease. The correlation matrix of Table 7.5 shows that progress in one field of language learning is well correlated with progress in all other fields, except for articulation.
The variables of the matrix are all dichotomized and qualitative; the data for the correlations are shown in the six contingencies shown in Table 7.6 and 7.7.
The simultaneous unfolding of language,“across the board.” is of great importance for language theories. There is no a priori reason why a child who has stopped babbling and whose utterances are always attempts at saying words or phases, should also have a vocabulary of 50 words or more (he might be content to say the same five words again and again; or he might still be babbling randomly at times while already in possession of some hundred different words); nor is it immediately obvious why the postbabbler should have adequate understanding of spoken commands (he might have learned to imitate like a parrot); or that he should have the same facility in naming people as in naming classes of objects. The one exception to the rule of simultaneous unfolding of language skills is the children’s articulation. The lag is not due to structural abnormalities of fauces or tongue (see complete report, Lenneberg et al..1964)
這部份主要是在探討蒙古人其對語言及語言學習的特質性。首先，chronological age是比computed IQ's更來的好的一個對語言發展的預測值。要注意的是：對語言發展的標準判斷是每個言語的優勢辭彙和片語以及缺少或只是少量的隨意亂語。研究發現語言發展和學步有一定程度的相關。
蒙古的小孩最令人關注的是其簡單卻又柔情始終愉悅的心情的特質，和比一般大眾依賴著雙親的照顧。書中懷疑雙親的照顧依賴還有過度的babbling以及模仿的傾向是否是影響語言發展的重要因素。因此，自然地 mentation會被認為並不足夠造成快速的語言發展的進行。我們相信每個人皆有一個天生故有的演化機制，策略決定行進的步驟。Table7.5指出不同的語言學習區域是彼此相關的。比如Extent of naming和 understanding 或是和vocabulary都有相關性。
對語言同時發展的理論而言across the board是個很重要的理論。在先前沒有理由可以解釋babbling的停止以及我們總是傾向說出字詞和片語的現象，還有怎麼能擁有50或更多字彙的能力等等種種現象……