Blind Alley Developments in Childrens’ Language Acquisition

Definition

A blind alley development (BAD) is a rarely occurring ephemeral development of young children that systematically deviates from parental input and is eventually abandoned due to persistent explicit and/or implicit correction by the children’s caregivers.

1. Introduction

Typically, young children’s language outputs successively approach their inputs (from their parents, peers, other caregivers and teachers), until they are identical or nearly so. But rarely, they create ephemeral Blind Alley Developments (BADs), which systematically deviate from their inputs in the course of their monolingual or simultaneous bilingual language acquisition. These developments in morphology and syntax have either no source in the target language and in their parental input (strong BADs: the examples come from Greek, Russian and Polish) or if they have one (weak BADs: the examples come from Greek, German, Croatian and French), they systematically develop their production in a wrong direction away from their parental inputs, in contrast to the typical developments where children’s outputs successively approach more and more parental inputs. In the case of simultaneous bilingual acquisition (since birth), children can produce a specific weak BAD of an overlay of the two languages’ target structures, so that the four Viennese children that are observed, form German noun plurals according to Croatian conditions and Croatian noun plurals according to German conditions. For their analysis, the conception of superposition in quantum physics can be used that Mattiello and Dressler [1] had already adapted to linguistics. Nobody else before has detected, analysed and explained these phenomena. Whereas no acquisition models other than the Natural Linguistic model can explain strong morphological BADs, except with fundamental changes in their models; weak morphological BADs and the Polish strong syntactic BAD discussed could be explained by other models, if they adopt argumentations described in this contribution.

BADs represent the best evidence that children do not simply imitate their parents, etc., but self-organise their language acquisition (autopoiesis). The explanation of such radical types of self-organisation may be considered to fall into the trap of Feyerabend’s principle of “Anything goes!”, which renders decisions between competing explanations impossible or difficult. We think that we have overcome this danger.

Another type of self-organisation occurs much earlier in the premorphological period, when children rather unsystematically create few examples of extragrammatical morphological patterns, especially reduplications, blends and onomatopoetic forms such as echo words. These unsystematic developments such as G. mapi, a blend of Mama ‘mumj’ and Pap+i ‘dadd+y’ or the hypocoristic Lis+i (which has become permanent for my elder daughter) from Elisabeth, are not discussed in this entry, which exclusively analyses and explains the systematic, albeit ephemeral developments of BADs.

This premorphological period is followed by the protomorphological period, when children start to acquire adult structures, until they acquire the core of adult morphology (cf. [2,3]).

The linguistic model espoused in this entry is that of Natural Linguistics [4,5]: it is a semiotic and cognitive model of universal parametrized preferences, e.g., for iconic relations between form and meaning and for expressing marked morphological and syntactic structures by more salience than their unmarked counterparts. Children can follow a universal preference in a production, even if they do not find an example of it in their input. In contrast, input-based acquisition models (incl. Constructional Morphology and Syntax) postulate that children can produce only what they have found in their language input. Generative nativist models rely for child acquisition on specific (not semiotically- or cognitively-based) linguistic parameters of Universal Grammar. Since cognitive and semiotic bases must be assumed for children’s maturation, this contradicts Occam’s Razor. Moreover, no respective parameters have been assumed so far for the Blind Alley Developments discussed in this contribution.

The language acquisition model on which this entry is based not only fits to the above characterised linguistic model, but conforms to the universally accepted methodology of MacWhinney [6] with specifications described in the appendix on methods, plus Popperian falsificationism in the interpretation of unclear cases according to [7].

2. Data Collection and Methodology of Analysis

All the data have been collected by recording spontaneous verbal interactions of young children with their parents (mainly mothers). This method of data gathering leads to ecologically much more valid and more reliable results than data gathered via experimental tests with children (Gallant et al. 2021, [8]); for example, 8-year-old German-acquiring children produce in formal plural tests errors that sociolinguistically and psycholinguistically comparable children cease to produce at 3 years of age or even much earlier. Data analysis followed the universally accepted principles of MacWhinney’s [6] CHILDES project (Materials and Methods section in Supplementary Materials).

3. Blind Alley Developments (BADs)

Blind Alley Developments (BADs) were first detected, analysed and explained by Dressler et al. [9]. These analyses have been further developed in Čamber and Dressler [10], Dressler and Payne [11] and Kononenko-Szoszkiewicz and Dressler [12]. Young children rarely develop such ephemeral paths of acquisition, which they have to give up soon because of consistently opposed explicit and/or implicit parental inputs.

3.1. Strong BADs

Strong BADs are paths of children’s output developments which have no source in any input (nor in the target structures of the respective languages). Strong morphological BADs cannot be explained by current theoretical acquisition models, except by that of Natural Linguistics.

3.1.1. Strong Morphological BADs

The most spectacular example found is the acquisition of the Greek subjunctive in two successive strong morphological BADs. Also, in Greek, the subjunctive is the marked syntactic and morphological category in opposition to its unmarked counterpart, the indicative. The subjunctive must be learned soon because it is generally used as a jussive and in secondary clauses, including uses which are expressed in other languages by infinitives, which Modern Greek lacks. It is formed from the indicative by preposing the unstressed particle, e.g., in kán+i ‘(she/he) makes’ ➔ na kán+i.

The boy’s first strong BAD was produced for more than two weeks systematically (from the end of 1;10 onwards): he always omitted the unstressed proclitic particle (which has parallels in most languages); instead, he lengthened the stressed verbal stem vowel and produced ká:n+i. A similar example of a different type is the aorist (=perfective) subjunctive na kóp+s+i ➔ kó:p+i ‘she should cut’; the boy produced more than 40 tokens of subjunctive lengthening. However, Modern Greek has neither long vowel phonemes nor non-emphatic phonetic vowel lengthening (in addition, consonant lengthening is also only emphatic). Thus, this subjunctive vowel lengthening has no source in the target structure nor in the boy’s inputs.

Obviously shocked by the parents’ opposition, the boy did not try to produce a subjunctive. Then he developed a second strong morphological BAD and used it for six weeks: verb-initial open-syllable reduplication, thus ka+kán+i, ko+kóp+i. However, Modern Greek has no morphological verbal reduplication, except in a few isolated fossils from Ancient Greek, which have neither subjunctive meaning nor a non-reduplicative counterpart.

Most acquisitionists use input-based models (i.e., their basic principle is that children’s outputs are based on parental inputs), so they cannot explain these two strong morphological BADs. A minority of acquisitionists adhere to nativist generative models, i.e., they postulate that children’s acquisition is based on inborn parameters. However, their models do not include inborn parameters for vowel lengthening or initial reduplication used for expressing marked categories.

In contrast, Natural Morphology (henceforth NM) assumes that early child language is very iconic and that marked categories have more meaning than unmarked categories. Therefore, it is an iconic operation to express more meaning by more form. Vowel lengthening of the marked subjunctive is therefore iconic. Morphological reduplication of an open syllable is still more iconic, because formal addition of two phonemes is more transparent than phonetic lengthening of a vowel. Moreover, it fits NM that the more iconic, and thus more natural operation, is adopted after a less natural operation and lasts for a longer time period.

The other BADs must be analysed in a less detailed manner, both in order to avoid unnecessary repetitions and to not exceed the allowed number of words.

The second strong morphological BAD of this entry concerns verb-initial open-syllable reduplication produced by seven Russian children (two girls and five boys) to express very iconically iterativity (thus, iconicity is very transparent, because it consists of repetition of both meaning and form) and less iconically, the durative aktionsart of the imperfective verbal aspect.

One of the few examples of iterativity from the premorphological period is onomatopoetic bax-bax (girl one, 1;2.7, while knocking on various objects around her) vs. bax (1;2.21, referring to one object that fell down).

More examples come from the protomorphological period. At 2;6, boy one created from the verb stuk+nu+t’ ‘to hammer’ the reduplicated verb root plus a correct 1.Sg.Pres. from a related verb: tuk-tuk, stuč+u ‘I’m hammering again and again, I’m hammering (imperfective aspect, which also can express iterativity)’. At 2;5, girl one created from the verb beg+a+t’ ‘to run’ in addition to the correct 3.Sg.Pres. a reduplication of the verb root in: oj, kak be-ž+it, tak: beg-beg ‘Oh how (the puddle) run+s: run-run (rather durative than iterative ‘forth and back’, with a phonological simplification of the word-initial consonant cluster and the/k/of the verb root)’.

A clearly durative example is as follows: at 1;4, boy 2’s (in reference to another boy’s running) premorphological verb-root reduplication gom-gom ‘run-run’ from adult beg+om ‘we are running’,

Also, Russian has, despite its very rich derivation system, no verb reduplication. Thus, this is another strong morphological BAD.

The strong morphological BADs, which all come from inflectional verb morphology, can so far only be explained within the model of NatMorph.

3.1.2. A Strong Syntactic BAD

The strong syntactic BAD occurring in the early stages of the acquisition of Polish negative sentences has been first observed but neither analysed nor explained by Sopata [13]. The presentation is based on Kononenko-Szoszkiewicz and Dressler (2025) [12]. The target structures of negation are as follows: sentence negation is signalled by preposing the unstressed negative particle nie not, e.g., Nie czek+a+m ‘I dont wait, lit. Not wait I;

The simplest target structure is the one-word answer Nie‚ No’ (stressed);

A much rarer subtype is ‚I say No‘, also with stressed negation;

A later acquisition is the unstressed negative prefix nie+‚ un+, non+, e.g., nie+delikat+ny ‘un+delicate+adj.suffix‘;

The latest acquisition is negative concord, where a negative submorpheme n-precedes the subject and possible objects and adverbs in addition to the unstressed particle (before the verb).

The phases in the acquisition of sentence negation are as follows:

(a) Holophrastic negation = isolated uses of nie; the first example was produced at 1;2;

(b) nie ma, there is not‘ emerges at 1;10: it looks only in orthography like a correct sentence negation. In reality it is a lexicalized phrase (lit., not has‘) with the normal Polish penultimate stress;

(c) The main BAD phase of producing a verb with the postposed and stressed negative (particle from 2,1 through 2;2), which shows that they are productively and systematically used, characterised by non-canonical post-predicate placement of stressed nie. In its first subphase the predicate is omitted, but the negative particle is stressed. Evidence of the status of a BAD is as follows: Kask nie, (I) do not (want) the helmet, lit. helmet nót‘. The first example with an overtly present verb is at 2;2: Idzie+my tutaj nie ‘We don’t go here, lit. go+we here nót’;

(d) A transitional phase (starting with 2;3), where BAD and emergent correct sentence negation co-occur. The first correct example is Nie mog+ę ‘I cannot, lit. Not can+I’;

(e) By approximately 30 months of age, children master correct sentence negation, i.e., they produce consistently only correct sentence negation in diverse syntactic contexts, without any occurrence of the BAD.

Our explanation of the Polish strong syntactic BAD, that has been found in all the six children observed, has the following stages:

(A) Also, in Polish, negative sentences are on the meaning level of the marked syntactic counterparts of the unmarked positive sentences. Therefore, positive sentences emerge and are mastered considerably more than negative sentences, cf. [4,14].

(B) A different degree of salience is one universal strategy for distinguishing marked from unmarked grammatical categories, i.e., marked categories are signalled by greater salience, cf. [15,16].

(C) Stressing the negation particle increases prosodic salience.

(D) Postposing it increases in children’s acquisition of positional salience, due to the recency effect in young childhood [17,18], i.e., ends of units are perceived and learnt earlier than initial and especially interior parts of units.

(D′) The recency effect shows not only in the BAD analysed here, but generally in young children’s production, including abbreviations, e.g., G. Schokolade ‚chocolate‘ is produced by children as lad+i (with the childish diminutive suffix +i), only much later as Schoko (due to the opposite adult primacy effect, which favours the beginning of units).

In contrast to the strong morphological BADs discussed, which presently can be explained only by NatLing, this strong syntactic BAD could be easily integrated into all other acquisition models if they analyse this BAD, provided that they include syntactic markedness into their explanation and choose to use positional and prosodic saliency as an explanatory principle. This could be achieved for other Slavic languages as well, such as Ukrainian and Croatian.

3.2. Weak BADs

Weak BADs have a source in children’s input but they develop against this input until they give it up due to constant explicit and/or implicit contradiction by their parents or older conversation participants, whereas normally children’s outputs more and more approach the structures of their inputs. The weak BADs discussed here come from different language areas.

Before I shall report the essentials of the Greek, German and French weak morphological BADs that have been investigated in Dressler et al. [9], I have to start with a BAD that occurs in many languages, namely the emergence and disappearance of fillers. It had been found and analysed within the corpora of two Swiss–French children in Dressler and Kilani-Schoch [5] but recognised as weak BADs only in [9]. French fillers, like those in other languages, originate by phonological reduction in a free, clitic or bound morpheme or a non-morphological non-salient part of a word to [a], e.g., in/atɔ/for encore ‘still’ at 1;7, and/a dɔr/for il dort/dɔr/‘is sleeping’ at 1;8.

Then a weak BAD developed by adding fillers before verbs where they cannot be derived from a non-salient reduced part of a preverbal morpheme: an example is the reduction in the preclitic unstressed first person singular pronoun je and the unstressed feminine definite article la to [a] in je vais chercher la petite assiette et la bavette et la cuillère pour manger, “I’m going to get the little plate and the spoon for eating” ➔ a va church+er a petite assiette li a cuillère pour mang+er ‘lit. filler is going to search the small plate for eat’ where li a contains both the two phonemes of the definite article la and the filler (with an unexplainable insertion of the vowel i). In the protomorphological period, fillers become even more grammatical, i.e., they acquire also a syntactic function: one girl frequently added filler/a/before a proper name (20 tokens), which can be analysed as corresponding to a deictic c’est ‘this is’ or to a cleft sentence c’est…qui, e.g., at 2;1 in a maman a donne ‘lit. filler mum filler gives’ for c’est maman qui donne ‘it’s Mum who gives’. Similar investigations of BADs developing from phonological fillers in other languages would be welcome.

The Greek diminutive suffixes can be combined but not repeated. However, the younger brother of the Greek boy who created two strong BADs (see above), produced for a short time the BAD of repeating the diminutive suffix -áki (neuter, being attached also to masculine and feminine nouns), as in skil+ak+áki from masc. skíl+os ‘dog’, pedh+ak+áki ← pedh+í‘child’ (neuter). He also produced when addressing his closest caregivers the vocatives bab-ák-aka from ‘dad’, mam-ák-aka from ‘mum’. Diminutive suffixes are typically repeated (expressing intensification of pragmatic or emotional meaning). Generally, diminutive suffixes (and only diminutive suffixes) can be and are often repeated in most European languages.

In French liaison, some word-final consonants morphonologically link to the initial vowel of a following word, as in partir en vacance ‘to leave for holidays’, which results in the third open syllable [rᾶ]. Another type of liaison is the overt appearance of an underlying word-final [z] before a word-initial vowel, as in faux ami [fozami] ‘false friend’ vs. faux document ‘false document’.

The younger of the two Swiss-French sisters combined both strategies for five months (2;2–2;7) into a weak BAD by inserting an unmotivated/r/between word-final and word-initial vowel, as in là-[r]-une vache ‘there (is) a cow’ at 2;4. Moreover, in analogy to infinitives ending in/+i+r/, she extended/r/-insertion to infinitives in/+e/, as in donner [=dɔne]-[r]-une bavette ‘give a bib’. Thus, she overextended liaison principles in a false direction away from the input, a weak BAD.

German compounds either simply concatenate their constituents (the unmarked morphological option) or also insert an interfix (or linking element) between the two constituents (the marked and therefore later acquired option, see [19]). The normal interfixes (except in many Latinate compounds, but these are irrelevant for young children) are unstressed -e-, -(e)n-, -(e)s-, -er-, -(e)ns. In respect to (non-)interfixation, a Viennese girl produced from 1;9 to 2;9 and a Viennese boy from 1;9 to 2;4 (an isolated example at 3;8), a weak morphological BAD of having a predominantly unstressed e at the boundary between the morphological constituents of compounds. This represents a conspiracy between (often wrong) interfixation and (often wrong) non-interfixation in order to arrive at an identical result. The boy produced many fewer BAD examples than the girl.

For example, at 1;9, the girl produced Hase+mama ‘rabbit mum’ without the correct -n-interfix, at 2;2 Kinn+e+sette instead of Kind+er+kassette ‘child-cassette’, at 2;11 Luft+e+bon+e for Luft+ballon+e ’air balloons’.

The boy produced, at 2;5, Platte+spieler ‘record-player’ without the correct -n-interfix, at 2;9 the novel compound Zwerg+e+spiel ’dwarf play’ with an added interfix, similarly, already at 2;4, Mickey+mäus+e+baby ‘mickey+mice+baby’ with an interfix/e/which is homophonous with the correct plural suffix.

Among the types of weak BADs observed there is a special type (or more precisely, there are two simultaneous, connected and analogical BADs) first observed, detected and analysed by Čamber and Dressler [10] in the course of acquisition of Croatian and German noun plurals by four Viennese children (one girl and three boys) in their simultaneous bilingual acquisition of both languages and then analysed and explained by them. In contrast to all the other BADs, the period of this BAD started much later, at 3;3. In contrast to simultaneous bilingual acquisition, no BADs have occurred in the thirty cases of successive bilingual acquisition of first Turkish at home, then of German in kindergarten analysed in Vienna, cf. [20].

Both languages have three genders, but the acquisition of Croatian noun plurals is because of several reasons much easier than of German plurals, whereas Croatian has no zero plurals (i.e., plural and singular being identical). German has productive zero plurals, which makes plural formation less distinctive; German has much more plural suffixes with a much less transparent distribution than Croatian; Croatian has, in contrast to German, a gender-distinctive plural agreement of attributive and predicative adjectives with the governing noun; Croatian has, again in contrast to German, gender-sensitive plural cases, and more cases than German, which incites children to devote more attention to the acquisition of inflections (cf. [21]); as to morphonological changes in the plural which can slow down acquisition, German has much more umlaut (metaphony) than Croatian palatalisation. Croatian and German have just one homophonous suffix, unstressed +e. But where this suffix is restricted to nouns ending in -a (mostly feminines, but also masculines, similar to Latin, the more frequent masculine nouns ending in consonants have +i-plurals, all neuters have +a-plurals), +e-plural formation is much more complex: it is very productive with masculine nouns, less productive with neuter nouns and completely unproductive with feminine nouns. As a result, Croatian plurals emerged and were mastered earlier than German plurals.

But this presentation is limited to overproduction and overgeneralisation of the homophonous suffix +e and the impact of the mutual overlay of the target structures of both languages. Due to the exclusive homophony of only this suffix, its token frequency is much higher than that of all other suffixes of both languages, which explains their overgeneralization.

The suffix +e was overgeneralised in German, e.g., Bild+e instead of correct, but unproductive Bild+er ‘pictures (girl at 3;3, boy 1 4;9), Mantel+e ‘coats’ instead of the unproductive umlaut plural Mäntel (Filip 4;0). All four children produced in Croatian instead of masc. krevet+i ‘beds’ krevet+e, which is more incorrect (i.e., more distant from the target) than the German examples above; the boy 2 also used vake instead of masc. vlak+i ‘trains’ (with simplification of the word-initial consonant cluster). Even the obligatory Croatian neuter plurals in +a were replaced by +e in two instances: sel+e ‘villages’, djec+e ‘children’, because German has moderately productive neuter plurals in +e.

The overlay of the target structures of both languages had several results: the production of totally illegal Croatian zero plurals, whereas there occurred much less zero plurals in German than in the production of children who acquired only German; less German umlaut plurals than were produced by monolinguals; the occurrence of the above cited examples krevet+e and vak+e have also a second cause: German +e-plurals are most productive with masculine nouns ending in a consonant.

For the explanation of this overlay, the concept of superposition that Mattiello and Dressler [1] had already adapted from modern quantum physics was used: there, the paradigmatic example is light which has been proven to function simultaneously and under the same conditions as waves and particles, which contradict each other in classical epistemological perspective. Analogically, most conditions of plural formation in Croatian and German contradict each other, but they must be simultaneously present in the production of the BAD.

4. Conclusions

Strong morphological BADs cannot be explained on the one hand by current usage-based acquisition models insofar as these insist that children‘s language acquisition is always based on children‘s input from child-directed speech, including construction models (see [22,23]).

On the other hand, current nativist acquisition models cannot explain strong morphological BADs, because there is in generative Universal Grammar no principle or parameter (including parameter setting principles) which could be the base for such BADs or restrict conceivable BADs. Even in the most recent morphology-theoretical publications of Yang ([24,25]; cf. [26,27]) there is no pertinent explanatory principle on how strong BADs originate, although they contribute to the topic how children cease to produce BADs, cf. [11]. Clearly, adherents of such models could be able to introduce and justify new pertinent parameters.

Weak BADs and the Polish strong syntactic BAD can be fitted into other acquisition models, if they adopt the respective methodological principles of applying concepts of markedness and salience followed here, because there is no mutual incompatibility between our and other models in this respect.

Children finish their BADs due to constant explicit and/or implicit opposition of their communication partners to their BADs. But this concept can be refined by the adaptation of Yang’s Tolerance Principle ([28]), which is a model of how linguistic generalisations are formed by children beyond a finite sample of data in their inputs. According to this principle, children must receive (and I add: also interpret correctly) enough evidence of correct usage in their inputs, cf. [11]. Obviously, some children may have more resilience in resisting environmental influence and thus persist in their BADs for a longer time.

Labov [29] (p. 416) pointed out that “children must learn to talk differently from their mothers” and considers this an important source of language change. In contrast, BADs cannot lead to language change, because children must give them up too early.

The use of the concept of superposition in human sciences has a historical antecedent in the famous philosopher Georg Wilhelm Friedrich Hegel’s conception of synthesis of thesis and antithesis, which is at least implicitly followed in historical studies, including diachronic linguistics, cf. [1].

Strong BADs as the most radical instances of self-organisation (autopoiesis, cf. [11] and for exaptation as another type [30]) and therefore they are rare. Children’s self-organisation of their language acquisition without influence by children’s inputs (as in the case of strong BADs) is in danger of being subject to the epistemological scandal of Paul Feyerabend’s “Anything goes!”. However, due to its foundation in semiotics and cognition, NatMorph can avoid this danger for BADs and we think we have already found the most important types of strong morphological BADs. As to syntactic BADs, children’s overuse of bare (also called root) infinitives has typical generative theoretical interpretations. These are probably illusionary, because they could be reinterpreted as weak BADs in languages where present infinitives are a base form of verbs and where infinitives often occur clause- or sentence-final positions, which are positionally salient for children (cf. for Dutch Gillis [31], for German and French [32] and for Russian [33].

Weak BADs could be construed as analogical developments, but all analogical developments in the course of language acquisition assumed in recent work include a much closer link between children’s outputs and inputs. Drastic and systematic developments away from the input targets, as they occur in BADs, have not been assumed in studies on the acquisition of morphology except in our work on BADs.