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Before attempting to look into aspects of the acquisition of signed languages there are a couple of points that need to be made concerning their nature and their social status. It is not unnecessary to begin this way because external factors dramatically affect the way and the time signers learn and start using their language.

A first point to be made is that signed languages have hardly been considered to be proper languages by both (hearing) scientists and laymen, it is only in the last three decades that this prejudice has begun to yield. Nevertheless, signed languages are minority languages: it is not the case that any of them has enjoyed an official status or anything close to recognition and acceptance. Even up to this point, a state of prohibition and/ or persecution against signing can be assumed.

Sign is in use among the small and dispersed group of deaf people only: we do not know of any hearing communities that have adopted a language in the visual modality, instead of the mainstream auditory one. In addition, a hearing child can acquire any language (spoken or signed), provided she is exposed to the relevant stimuli the appropriate time where a profoundly deaf person has a choice among signed languages only. It is also true that deaf people live and work among hearing people, more or less integrated in their society, forming a separate community of their own at the same time. Consequently, hearing children of deaf parents are going to be reluctant and/ or unable to belong to the deaf community; where deaf children of hearing parents may experience a difficulty in acquiring the sign language of their local deaf community in the natural manner, at the right time. Thus, it is not the case that Sign is handed down to the next generation the way most spoken languages are, as Sign is related to deaf people and, fortunately, deafness is not hereditary but for a number of cases only.

Moreover, there is the class of signers that consists of those who lost their hearing after childhood and have to learn the sign language of their local deaf community as a second language; unlike what happens with spoken languages, ‘late signers’ constitute an important part of the deaf/ signing community.

The fact that Sign exploits the visual modality and the ‘special conditions’ under which it is acquired and used might provide us with a unique perspective with regard to problems that have to do with the acquisition of language in general: whether linguistic development is parasitic on general cognitive capacities and if there is a critical period for L1 acquisition or not. Before this, though, it must be made clear that signed languages are ‘normal’ natural languages and that the course of acquiring a signed language is parallel to the course of acquiring a spoken one. We will attempt to draw arguments in favour of this assumption mainly from aspects of the way Sign morphology and vocabulary are acquired and the striking similarities between the process of Sign acquisition and the acquisition of spoken languages.

We have to argue for the linguistic nature of signed languages as they are not arbitrary in the saussurean sense, so we have a case of change of paradigm when we treat Sign as language. This is so because a considerable part of the vocabulary in the signed languages of the world consists of signs that bear resemblance to their referent, unlike spoken languages where cases of iconicity are restricted to the marginal cases of onomatopoeias (words mimicking sounds like ‘miaow’ or ‘boom’). In the structuralist paradigm, arbitrariness is a necessary condition for a system to be characterised as a language; in a generative framework, on the other hand, a system is a natural language if it abides by UG and, consequently, if it is acquired the way the rest of natural languages do. This is exactly what we aim to show here.

Generally speaking, children acquiring Sign as their first language seem to ‘ignore’ that the high degree of iconicity the vocabulary presents could make the course of acquisition easier for them. We will present three instances of the absence of substantial impact of iconicity on acquiring Sign, beginning with an apparent counterexample to our assumption.

Just like the production of the first word by hearing babies is the first real milestone of ‘learning the language’, the first sign is of a comparable importance. Just like first words, those first signs constitute free (unbound) linguistic forms and they are recognised as proper signs by the adult signers.

There is a very interesting fact concerning the time that the first sign appears. It is known that the first word appears around the first year of life, the age the first sign appears being considerably earlier: from as early as 5½ months to a mean of 8½ . So, one might connect this early onset of lexical acquisition to the iconicity of Sign, which would facilitate the whole procedure. Nevertheless, only one third of signs in early vocabularies can be considered iconic, this meaning that it is not the case that children learn first (and faster) the most transparent signs. Furthermore, it is not obvious that what adults perceive as the iconic element of signs is as salient to the young signer: the etymology of signs presupposes knowledge of the world a toddler can neither possess nor is cognitively equipped to access. An often-cited example is the sign MILK that features (as expected) among early vocabularies and that mimics the act of milking a cow: it is highly unlikely that an infant is either aware of the relation between the particular movement and handshape and the white drink, or even that she can associate these two actions: signing MILK and milking a cow (had she witnessed both).

Sign exploits its visual medium in grammaticising space. This is the case with both pronominal/ anaphoric reference and verb agreement. As far as verb inflection is concerned, the nominals the verb agrees with (subject and object mainly) are assigned positions in space: the actual of their referents or surrogate ones -if recoverable, abstract loci in all other cases. The verb is then signed from the subject position/ locus towards the object one. In the case of verbs like GIVE, when ME and YOU are the subject and the object respectively, in signed languages such as ASL and BSL, this inflected form resembles a pantomimic depiction of giving a small object to the addressee and it is certainly more iconic than the plain citation form.

In contrast to what one might expect, children acquiring Sign do not take advantage of this fact and do not just imitate this ‘pantomime'; on the contrary, they learn and use the citation forms first. Highly relevant are the findings in Meier’s dissertation that children acquire verb agreement as a morphological system independently of iconicity, instead of being guided by the mimetic properties of agreement or its spatial analogies to real space.

The verbs of movement tend to be most iconic in Sign, virtually resembling the kind of pantomime of the movement itself with which hearing people sometimes accompany their utterances. So, at a first inspection, the sign for VEHICLE-GOING-UP-HILL, for example, is just a pantomimic representation of a car going uphill, as it consists of moving the hand upwards at an angle.

However restricted the inventory of components and combinations to depict movement may be, one would expect the children to perform pantomime, imitating the way those verbs of movement actually look like. Newport and Supalla conducted an experiment in which deaf children were asked to describe in ASL the movement of objects on a film they were shown; the results were surprising. Simple movements (i.e., those monomorphemic in their adult forms) were produced correctly virtually 100% of the time throughout the period from 2½ to 5 years, although the moving objects on the film did not follow the same track of movement (e.g. arc or downward) as the direction of signing. On the other hand, complex movements (i.e. those requiring more than one morpheme in their adult forms) were often avoided, particularly by the youngest child, and were replaced with frozen signs which were reproduced the same over a range of contrasting cases of movement. For example, to describe an object falling, children would produce the same sign FALL in its citation form regardless of what fell and the direction it fell; no child would just mimic what they saw.

It should be more than clear that iconicity does not make Sign less ‘linguistic’ than spoken languages -as children ignore its transparent aspects while acquiring it. Children learn ‘rich’ morphology in a standard way: citation forms first, then analytical approach involving linear sequencing of distinct morphemes to end up with the correct forms. In the early stages only citation forms (preferably consisting of simple movements) are produced correctly; later, children master the ability to look into signs and see morphemes, but they still produce only some morphemes correctly and omit others. Sometimes, this stage is followed by the production of multiple morphemes, though produced sequentially. It is even later that the correct forms, with simultaneous articulation of the consisting morphemes, are produced, that is the forms that actually resemble to pantomimic depiction. Thus, children acquiring Sign learn citation forms first and then analyse their input in morphemes -they do not just imitate. Moreover, as Meier and Newport (1990:10) put it: "the timing of the acquisition of morphology reflects language typology rather than language modality". Not only the timing, we would add in respect to the data presented above, but the specific strategy as well.

We have already implied that the children treat the iconic and non-iconic lexical items of Sign in the same way and that they learn the morphology of a language irrespective of modality, moving from citation forms to analysed morphemes. In fact, not only are children blind to the transparency of grammatical forms, but they also treat gestures and grammatically meaningful signs in different ways -just like children learning English, who treat a schwa of doubt differently from the indefinite article "a".

Petitto (1987) studied the acquisition of personal pronouns in ASL by two deaf signing children. This class of signs exhibits the property of resembling the pointing gestures hearing people make to designate people, things or places. One might expect, once more, that their iconic properties would make them easy -if anything- to acquire. The story is slightly more complicated (and interesting) though.

By the ages between 0;10 and 1;0, Petitto’s subjects started pointing to objects, places, and people, the way that all children do. Between 1;0 and 1;6, they stopped pointing to themselves and other people -although they would continue "to point to objects, locations and events around them". Immediately afterwards, the children started using the personal pronouns YOU and ME but in an incorrect way -one of the children consistently: they performed reversal errors, that is they produced the YOU sign although a reference to themselves was intended. Additionally, the subject mentioned above "referred to herself (when not using YOU in self reference) with the sign GIRL...She did not use second and third person pronouns, but instead referred to people in these roles by using full proper nouns"; at the same time her (non-linguistic) pointing was not affected whatsoever. Not surprisingly, by now, it is exactly the same kind of mistakes that hearing children usually make with the arbitrary personal pronouns of spoken languages.

A first implication is that "the data suggest that the...child shifts from conceptualising person pointing as part of the class of deictic gestures to viewing them as elements within the linguistic, or grammatical, system of ASL". As we have seen, this is also the case with verbs of movement and inflected verbs: they are absorbed and treated as a special kind of knowledge, no matter the degree of resemblance they bear to mimetic/ pantomimic non-linguistic gestures. It is this very distinct treatment of a particular part of a homogeneous material (i.e. gestures and signs) and the fact that this treatment is the same as speech input receives, that imply the presence of a cognitive mechanism that is tuned into recognising linguistic data regardless of the modality in which they are available. Furthermore, it must also be the case that this cognitive mechanism is not parasitic on other cognitive capacities, like the one that enables children to perform gestures, pointing included. If we turn again to the data provided by Petitto, there occurs a period when children stop pointing at themselves and other people while they go on using gestures to attract attention to objects and events. So, pointing goes on during this period between ages 1 and 1;6 but a part of it disappears, the part that is to be replaced with the linguistic function of pronominal anaphora. We have a very interesting hint here: the developing of pronominal anaphora does not evolve smoothly, by some kind of specialisation, from the rest of the gesturing strategy in an uninterrupted and continuous way. There is a gap (a "shift") between non-linguistic pointing to people and the developing of pronominal anaphora, a gap that is also evident by this intermediate period of ‘pointing silence’, lasting six months.

Consequently, based on the evidence above, we would find it hard to suggest that the mechanism (Chomsky called it "device") that acquires L1 is parasitic on general cognitive capacities the child develops at this age. First of all, if anything, it is too subtle, capable of picking out only the data that abide with UG constraints -in a manual/ visual modality in our case- out of a purport of homogeneous data. This is strange when it comes to children up to the age of 1;6, especially if we consider the varying cognitive stages the children may be in and the stage of general cognitive maturation of human beings at that age. Moreover, the gap we referred to above is highly suggestive, in a dramatic way, of the discontinuity between general cognitive and linguistic maturation.

We could now postulate (considering the subtlety of this ‘Language Acquisition Device’) that eventually it is not a learning mechanism -a mechanism that seeks to formulate mental representations according to input. It is rather a mechanism that seeks out and selects the appropriate data from within the purport the active modality (visuomotor, in the case of Sign) makes available. Not only is the Language Acquisition Device independent from the rest of the cognitive maturation, we claim, but it is innate as well, as it can perform (yielding a highly unfamiliar output, of course) even in conditions of extreme poverty of stimulus. But it takes more evidence to support our last claim.

We have reached a point where the question of the innateness of language is raised. A feasible (?) way to check this out would be to deprive children of any linguistic stimulus and see what kind of language they would develop (if any at all). Thankfully, there is no evidence (other than anecdotal of the sort the title alludes to) that anyone has tried deliberately to perform such an experiment. The cases of ‘wild children’ provide us with considerable insight, although things in their cases are too complicated, as they are generally deprived of more things than just linguistic input (human contact and/ or affection included).

The fact that 90% of deaf children cannot have the kind of linguistic stimulus required to develop a signed language -being born to hearing parents who may have not even heard of Sign- results in some of them acquiring Sign at a later age, developing what signers call ‘home signs’ in the meantime. It would be most interesting, with regard to the above, to look into the nature of this kind of ‘private sign language’. Goldin-Meadow and Mylander have studied ten deaf children’s developing of home signs in their attempt to communicate with their non-signing parents.

First of all, it would be useful to point out that the children in question were not entirely deprived of gestural input from their parents. Nevertheless, they went beyond this input and the important fact is that "the developmental course of the deaf child's gestures was comparable to the development of words or signs in children acquiring conventional languages". At an early stage, the children would produce isolated pointing gestures or of a highly iconic nature. For example, the gesture for "open jar" would be a twisting movement of the hand and so on. Nevertheless, there was a development within this ‘private lexicon’ on the making. The children created "a system of handshape and motion morphemes [and] used only a restricted number of values on each of the dimensions we coded; in fact, 5 hand shape and 9 motion forms accounted for 99% of the forms... produced.". In other words, the children manipulated their iconic gestures so that they be composed from a restricted directory of morphemes. Thus, the children in those studies displayed the pattern of morphological development observed for deaf and hearing children acquiring conventional languages: a period of unanalysed amalgams (frozen forms or citation forms) followed by a period of analysis into meaningful components. The fact that the input was restricted and not of a linguistic nature seems to have affected the emergence of morphology in a marginal way only.

Soon the children started combining gestures, concatenating them in a temporally continuous manner so that those ‘sentences’ were not randomly ordered but, eventually, they "were structured on the surface as are the sentences of early child language". As the formations would become more numerous and more complicated, it was obvious that ‘word order’ in them could not have been borrowed by either ASL or English, as it showed properties analogous to "the structural case-marking patterns of ergative languages in that the intransitive actor is treated like the patient rather than the transitive actor". Mutatis mutandis, the syntactic development of the children in this study was parallel to that of children acquiring normal language models, spoken or signed. This is also true of the overall semantic structure of those ‘sentences’: there was a degree of organisation of the predicate frames; the structures would be constructed giving prominence to the thematic role of patient; the first elements of recursion were present, as well.

The course of acquisition (or, rather, the (re)construction) of signed morphology and aspects of Sign vocabulary (like pronouns) suggests that, whether there is enough input of a fairly homogeneous (that is, visuomotor) nature, or no input at all, a mechanism independent of the rest of cognitive capacities exists, responsible for carrying out the (re)construction of language. The next question would be if there is a critical period during which this mechanism is operational, or not. The fact that many signers acquire their first language after childhood, provides us with valuable insight on the subject.

Some of us know intuitively that it is hard to learn any other language the way you know your mother tongue, that it takes longer and is considerably more effortful. But, what if you never had the chance to possess a first language before the end of the childhood? Provided that a ‘Language Acquisition Device’ is responsible for the acquisition of the first language, is this mechanism active after childhood at all? Given the fact that most signers (even among the congenitally deaf) are late signers, we are provided with a good means of testing whether the Language Acquisition Device is active during a critical period only (after which it becomes inert), or whether it can wait as long as required.

Rachel Mayberry studied three groups of signers: native signers who acquired Sign during childhood, late signers who acquired it as a second language (their hearing impairment not being so severe to totally deprive them of speech input) and, thirdly, signers who acquired sign as a first language after childhood. She tested the three groups in tasks involving immediate recall of sentences in Sign and shadowing.

As far as the first group is concerned, that is native signers, they "significantly outperformed" non-native signers, as they were able to recall more preserved lexical stems. Apart from omissions, the most common mistakes they would come up with when recalling or shadowing long sentences would be of a semantic nature, that is substituting signs for synonyms, where non-native signers would do phonological substitutions. The first thing we can observe here is that this suggests a difference between promptly comprehending the utterances presented and basically imitating the form of the signs when under pressure and short of memory.

As far as the two groups of late L1 and late L2 are concerned, the age of acquisition was inversely proportional to the grammaticality of the sentences produced. Even in cases when two subjects acquired Sign at the same age, their performance would differ in respect to whether they were late L1 or L2 learners, the latter outperforming the former. The results would remain the same even during an experiment in which special care was taken so that the overall time of the subjects using Sign -no matter the age of acquisition- would be equal. A conclusion to these data is that "late-first language learner is intermittently stuck at the surface level of the structure". If we compare this conclusion with the ones that Galvan drew studying the late acquisition of morphology in Sign, then the implications are somehow clearer. Galvan points out that although both native and late signers use increasingly complex sentences (that is, more morphemes per sentence) as their course of acquiring Sign proceeds, native signers use the morpheme as their unit of analysis, where late signers treat signs as gestalts (what we called amalgams). This impairs later morphological developments after a certain point. As he puts it, "late signers show cognitive development without morphological development". Similar results were reported about the acquisition of facial morphology of Sign by adult L2 learners, namely that they are incapable of learning and using it in a linguistic -rather than a non-linguistic, that is affective - way as they cannot analyse facial morphology into morphemes.

The acquisition of a language during childhood is performed in a unique way, different to the way we learn a L2 or -indeed- anything else, and it is ‘administered’ by a Language Acquisition Device. We can postulate that it is precisely this mechanism that prompts the grammar to grow and enables the mind to recognise and analyse the morphemes of the input language, these two being indispensable events of L1 acquisition, as we have seen. On the other hand there exists a critical period during which this device is operational after which it falls into disuse, whether a language is actually acquired or not. This fact accounts for the poorer performance and the defective grammar late L1 signers possess: among other things they lack the appropriate tool for spontaneous morphological analysis. It also seems that L2 learners are given a clear advantage over late L1 ones as they have an L1 already installed.

If we are correct, we can now understand why it is adults that make use of the iconicity of Sign in order to learn it: using the iconic properties of signs to connect them with their referents makes easier the task of remembering them. Iconicity provides adult learners with a key to memorise and unlock the, by then, morphologically obscure signs -remember that adults have no spontaneous way of perceiving and analysing signs as combinations of meaningful morphemes. This has to be so as language acquisition is now administered by their mind as a whole or, rather, by what Fodor calls the central system. After childhood, we learn a language just like we learn to play chess or, indeed, anything else.

• Bellugi, Ursula; van Hoek, Karen; Lillo-Martin, Diane Carolyn & O’Grady, Lucinda. 1993. The acquisition of syntax and space in young deaf signers. In: Bishop D. & Mogford K. (Eds.) Language Development in Exceptional Circumstances Hillsdale, NJ: Lawrence Erlbaum Associates. pp.132-149.
• Bonvillian, John & Patterson, Francine. 1993. Early Sign Language Acquisition in Children and Gorillas: Vocabulary Content and Sign Iconicity. First Language 13:315-338
• Bonvillian, John; Orlansky, Michael & Novack, Lesley Lazin. 1983. Developmental Milestones: Sign Language Acquisition and Motor Development. Child Development 54:1435-1445
• Carroll, John & Gibson, Eleanor. 1986. Infant perception of gestural contrasts: prerequisites for the acquisition of a visually specified language. Journal of Child Language 13:31-49
• Charrow, V. R. & Fletcher, J. D. 1974. English as the second language of deaf children. Developmental Psychology 10:463-470
• Chomsky, Noam. 1965. Aspects of the Theory of Syntax Cambridge, MA. MIT Press
• Chomsky, Noam. 1980. Rules and Representations New York: Columbia University Press
• Deuchar, Margaret & Stubbs, Michael. 1984. British Sign Language London: Routledge & Kegan Paul
• Fodor, Jerry. 1983. The Modularity of Mind Cambridge, MA: MIT Press
• Folven, Raymond; Bonvillian, John & Orlansky, Michael. 1985. Communicative Gestures and Early Sign Language Acquisition. First Language 5:129-143
• Galvan, Dennis. 1989. A Sensitive Period for the Acquisition of Complex Morphology: Evidence from American Sign Language. Papers and Reports on Child Language Development 28:107-114
• Goldin-Meadow, Susan & Mylander, Carolyn. 1990. Beyond the input given: the child’s role in the acquisition of language. Language 66, 323-355
• Groce, Nora Ellen. 1985. Everyone Here Spoke Sign Language Cambridge, MA: Harvard University Press
• Johnson, Jeanne; Watkins, Ruth & Rice, Mabel. 1992. Bimodal bilingual language development in a hearing child of deaf parents. Applied Psycholinguistics 13:31-52
• Jones, Michael & Quigley, Stephen. 1979. The Acquisition of Question Formation in Spoken English and American Sign Language by Two Hearing Children of Deaf Parents. Journal of Speech and Hearing Disorders 44:196-208
• Kayne, Richard. 1994. The Antisymmetry of Syntax Cambridge, MA: MIT Press
• Klima, Edward & Bellugi, Ursula. 1979. The Signs of Language Cambridge, MA: Harvard University Press
• Lenneberg, E.H. 1967. The Biological Foundations of Language New York: Wiley
• Masataka, Nobuo. 1995. Absence of Mirror-Reversal Tendency in Cutaneous Pattern Perception and Acquisition of a Signed Language in Deaf Children. British Journal of Developmental Psychology 13:97-106
• Mayberry, Rachel. 1993. First-language acquisition after childhood differs from second-language acquisition: the case of American Sign Language. Journal of Speech and Hearing Research 36:1258-1270
• Mayberry, Rachel. 1994. The Importance of Childhood to Language Acquisition: Evidence from American Sign Language. In: Goodman, Judith & Nusbaum, Howard (Eds.) The Development Of Speech Perception: The Transition From Speech Sounds To Spoken Words Cambridge, MA: The MIT Press. pp. 57-90
• McIntire, Marina & Reilly, Judy Snitzer. 1988. Nonmanual Behaviors in L1 & L2 Learners of American Sign Language. Sign Language Studies 61:351-375
• Mehler, Jacques; Jusczyk, G.; Lambertz G.; Halsted, N.; Bertoncini J. & Amiel-Tison C. 1988. A precursor of language acquisition in young infants. Cognition 29:143-178
• Meier, Richard & Newport, Elissa. 1990.Out of the hands of babes: on a possible sign advantage in language acquisition. Language 66:1-23
• Meier, Richard. 1991. Language Acquisition by Deaf Children. American Scientist 79:60-70
• Newport, Elissa & Meier, Richard. 1985. The acquisition of American Sign Language. In Slobin, Dan Isaac (Ed.) The Crosslinguistic Study of Language Acquisition Volume 1: The Data Hillsdale, NJ: Lawrence Erlbaum Associates. pp. 881-938
• Newport, Elissa & Supalla, T. 1980. The structuring of language: clues from the acquisition of signed and spoken language. In Bellugi, U. & Studdert-Kennedy, M. (Eds.) Signed and spoken language: Biological constraints on linguistic form Weinheim: Verlag Chemie
• Newport, Elissa L. 1984. Constraints on Learning: Studies in the Acquisition of American Sign Language. Papers and Reports on Child Language Development 23:1-22
• Orlansky, Michael & Bonvillian, John. 1985. Sign Language Acquisition: Language Development in Children of Deaf Parents and Implications for Other Populations. Merrill Palmer Quarterly 31:127-143
• Petitto, Laura. 1987. On the Autonomy of Language and Gesture: Evidence from the Acquisition of Personal Pronouns in American Sign Language. Cognition 27:127-143
• Piatelli-Palmarini, Massimo. 1989. Evolution, Selection and Cognition: from ‘Learning’ to Parameter Setting in Biology and in the Study of Language. Cognition 31:1-44
• Poizner, Howard; Klima, Edward & Bellugi Ursula. 1987. What the Hands Reveal about the Brain Cambridge, MA: MIT Press
• Reilly, Judy & McIntire, Marina. 1991.WHERE SHOE: The Acquisition of Wh-Questions in American Sign Language. Papers and Reports on Child Language Development 30:104-111
• Reilly, Judy Snitzer & Bellugi, Ursula. 1996. Competition on the Face: Affect and Language in ASL Motherese. Journal of Child Language 23:219-239
• Reilly, Judy Snitzer; McIntire, Marina & Bellugi, Ursula. 1990. The Acquisition of Conditionals in American Sign Language: Grammaticized Facial Expressions. Applied Psycholinguistics 11:369-392
• Reilly, Judy Snitzer; McIntire, Marina & Bellugi, Ursula. 1990. The Acquisition of Conditionals in American Sign Language: Grammaticized Facial Expressions. Applied Psycholinguistics 11:369-392
• Stokoe, W. C. 1960. Sign language structure: an outline of the visual communication system of the American deaf. Studies in Linguistics Occasional Papers 8.
• Studdert-Kennedy, Michael; Lane, Harlan. 1980. The Structuring of Language: Clues from the Differences between Signed and Spoken Language. In: Bellugi, U. & Studdert-Kennedy, M. (Eds.) Signed and spoken language: Biological constraints on linguistic form Weinheim: Verlag Chemie
• Wilbur, Ronnie & Jones, Michael. 1974. Some Aspects of the Acquisition of American Sign Language and English by Three Hearing Children of Deaf Parents. Papers from the Regional Meetings, Chicago Linguistic Society 10:742-749