Explaining color term typology with an evolutionary model

An expression-induction model was used to simulate the evolution of basic color terms to test Berlin and Kay's (1969) hypothesis that the typological patterns observed in basic color term systems are produced by a process of cultural evolution under the influence of biases resulting from the special properties of universal focal colors. Ten agents were simulated, each of which could learn color term denotations by generalizing from examples using Bayesian inference, and for which universal focal red, yellow, green, and blue were especially salient, but unevenly spaced in the perceptual color space. Conversations between these agents, in which agents would learn from one another, were simulated over several generations, and the languages emerging at the end of each simulation were investigated. The proportion of color terms of each type correlated closely with the equivalent frequencies found in the World Color Survey, and most of the emergent languages could be placed on one of the evolutionary trajectories proposed by Kay and Maffi (1999). The simulation therefore demonstrates how typological patterns can emerge as a result of learning biases acting over a period of time.     

Balancing Effort and Information Transmission During Language Acquisition: Evidence From Word Order and Case Marking

Across languages of the world, some grammatical patterns have been argued to be more common than expected by chance. These are sometimes referred to as (statistical) language universals. One such universal is the correlation between constituent order freedom and the presence of a case system in a language. Here, we explore whether this correlation can be explained by a bias to balance production effort and informativity of cues to grammatical function. Two groups of learners were presented with miniature artificial languages containing optional case marking and either flexible or fixed constituent order. Learners of the flexible order language used case marking significantly more often. This result parallels the typological correlation between constituent order flexibility and the presence of case marking in a language and provides a possible explanation for the historical development of Old English to Modern English, from flexible constituent order with case marking to relatively fixed order without case marking. In addition, learners of the flexible order language conditioned case marking on constituent order, using more case marking with the cross‐linguistically less frequent order, again mirroring typological data. These results suggest that some cross‐linguistic generalizations originate in functionally motivated biases operating during language learning.     

A Bayesian Model of Biases in Artificial Language Learning: The Case of a Word‐Order Universal

In this article, we develop a hierarchical Bayesian model of learning in a general type of artificial language‐learning experiment in which learners are exposed to a mixture of grammars representing the variation present in real learners’ input, particularly at times of language change. The modeling goal is to formalize and quantify hypothesized learning biases. The test case is an experiment ( Culbertson, Smolensky, & Legendre, 2012 ) targeting the learning of word‐order patterns in the nominal domain. The model identifies internal biases of the experimental participants, providing evidence that learners impose (possibly arbitrary) properties on the grammars they learn, potentially resulting in the cross‐linguistic regularities known as typological universals. Learners exposed to mixtures of artificial grammars tended to shift those mixtures in certain ways rather than others; the model reveals how learners’ inferences are systematically affected by specific prior biases. These biases are in line with a typological generalization—Greenberg's Universal 18—which bans a particular word‐order pattern relating nouns, adjectives, and numerals.     

Images to syntax: a neuropropositional model of language

This paper argues that language acquisition can be explained through the interactions of neural networks that represent images and words. Language development, according to the hypothesis to be presented, is largely a learning process in which grammatical rules are derived from the universal capability for recognizing, through spatial and temporal attributes of neural connectivity, case roles and propositions in perceived and imagined mental images. Neural patterns representing sounds and words are associated with image objects, and more abstract part-of-speech patterns form expectations that lead to syntactic rules. A conceptual model of the image-syntactic hypothesis is outlined in a series of steps to describe the transition from mental images to syntactic constructions.     

Relationships between language structure and language learning: the suffixing preference and grammatical categorization

It is a reasonable assumption that universal properties of natural languages are not accidental. They occur either because they are underwritten by genetic code, because they assist in language processing or language learning, or due to some combination of the two. In this paper we investigate one such language universal: the suffixing preference across the world's languages, whereby inflections tend to be added to the end of words. A corpus analysis of child-directed speech in English found that suffixes were more accurate at cuing the grammatical category of the root word than were prefixes. An artificial language experiment found that there was a learning advantage for suffixes over prefixes in terms of grammatical categorization within an artificial language. The results are consistent with an account of language universals that originate in general purpose learning mechanisms.     

On the preservation of word order in aphasia: cross-linguistic evidence

Studies of language production in English-speaking aphasics (both fluent and nonfluent) generally lead to the conclusion that word order is preserved to a much greater degree than grammatical morphology and/or lexical retrieval. However, because word order is rigidly preserved even in normal English speech, this pattern might reflect nothing more than "the weak link in the chain." Using a constrained production paradigm, we provide evidence showing that canonical sentence order is well preserved in both fluent and nonfluent patients, in Italian and German (languages that permit much more pragmatic word-order variation) as well as English. Patients also retain the ability to order nouns around a preposition, and among Italian patients, access to a high-frequency form of pragmatic word-order variation is also retained. Syntactic difficulties seem to revolve not around loss of ordering principles, but (1) reduction in syntactic complexity, (2) overuse of canonical word order as a "safe harbor," (3) blend errors in which a form appears in legal but semantically incorrect position, and (4) abandonment of the effort to produce a complete sentence under stressful conditions. We offer a redefinition of syntactic impairment as a problem in the access of phrase structure types, resulting in a preference for higher frequency forms. Parallels between lexical retrieval and phrase structure retrieval suggest that similar mechanisms may be at work in both cases.     

Using latent class analysis to test developmental models

While psychology in general has moved away from using typologies and toward using continua to conceptualize dimensions of behavior, certain aspects of learning and development are still fruitfully considered in typological terms. One reason for the abandonment of typologies was that a small number of types seemed unable to explain the enormous diversity of behavior. The development of statistical models such as latent class analysis has allowed theories involving types to be tested, and the allowance for errors of measurement explains how a small number of types can result in a large number of observed patterns of behavior. This paper demonstrates the application of latent class analysis in several areas of interest to developmental psychologists.     

The distributional structure of grammatical categories in speech to young children

We present a series of three analyses of young children's linguistic input to determine the distributional information it could plausibly offer to the process of grammatical category learning. Each analysis was conducted on four separate corpora from the CHILDES database (MacWhinney, 2000) of speech directed to children under 2;5. We showthat, in accord with other findings, a distributional analysis which categorizeswords based on their co‐occurrence patterns with surroundingwords successfully categorizes the majority of nouns and verbs. In Analyses 2 and 3, we attempt to make our analyses more closely relevant to natural language acquisition by adopting more realistic assumptions about howyoung children represent their input. In Analysis 2, we limit the distributional context by imposing phrase structure boundaries, and find that categorization improves even beyond that obtained from less limited contexts. In Analysis 3, we reduce the representation of input elements which young children might not fully process and we find that categorization is not adversely affected: Although noun categorization is worse than in Analyses 1 and 2, it is still good; and verb categorization actually improves. Overall, successful categorization of nouns and verbs is maintained across all analyses. These results provide promising support for theories of grammatical category formation involving distributional analysis, as long as these analyses are combined with appropriate assumptions about the child learner's computational biases and capabilities.     

What we know about what we have never heard before: Beyond phonetics : Reply to Peperkamp

Berent, Steriade, Lennertz, and Vaknin (2007) [Berent, I., Steriade, D., Lennertz, T., & Vaknin, V. (2007). What we know about what we have never heard: evidence from perceptual illusions. Cognition, 104, 591-630] demonstrate that English speakers’ perception of onsets that are unattested in their language mirrors their typological markedness. We suggest that these findings might reflect the presence of universal grammatical constraints, a proposal challenged by Peperkamp’s commentary. Our reply exposes mischaracterizations of our claims and presents additional empirical arguments in their support.     

Code switching by bilinguals: Evidence against a third grammar

Bilingual code switching within sentences (as in “The towel roja was dirty”) is often observed in bilingual communities. The present study addressed two issues. First, what is the nature of the grammatical rules that underlie code switching? Second, how do bilingual speakers acquire such rules? We addressed the first issue by obtaining judgments of the grammaticality of four types of sentences containing code-switched words. Judgments of acceptability seemed to be based on two rules: (1) Code switching can occur only when the code-switched words are positioned in accord with the rules for which they are approriate lexical items; (2) code switching within word boundaries is considered ungrammatical. We addressed the second issue by exploring the effects of age and code switching experience on the grammatical judgments of bilingual children and adults. Extensive code-switching experience did not seem to be necessary for bilingual speakers to know the grammatical constraints of code switching. This suggests that the constraints of code switching are based on the integration of the grammars of the two code-switched languages rather than on the creation of a third grammar. There were developmental changes in the judgments made to the sentences. All aged subjects found sentences that violated the word-order rule (1 above) unacceptable. However, the youngest children (8- to 10-year-olds) found mixing within a word acceptable. This developmental change could be due to a change in the grammar of code switching, in the ability to make metalinguistic judgments, or in the child's general knowledge about the nature of languages.     

Grammatical pattern learning by human infants and cotton-top tamarin monkeys

There is a surprising degree of overlapping structure evident across the languages of the world. One factor leading to cross-linguistic similarities may be constraints on human learning abilities. Linguistic structures that are easier for infants to learn should predominate in human languages. If correct, then (a) human infants should more readily acquire structures that are consistent with the form of natural language, whereas (b) non-human primates' patterns of learning should be less tightly linked to the structure of human languages. Prior experiments have not directly compared laboratory-based learning of grammatical structures by human infants and non-human primates, especially under comparable testing conditions and with similar materials. Five experiments with 12-month-old human infants and adult cotton-top tamarin monkeys addressed these predictions, employing comparable methods (familiarization-discrimination) and materials. Infants rapidly acquired complex grammatical structures by using statistically predictive patterns, failing to learn structures that lacked such patterns. In contrast, the tamarins only exploited predictive patterns when learning relatively simple grammatical structures. Infant learning abilities may serve both to facilitate natural language acquisition and to impose constraints on the structure of human languages.     

Grammatical properties of sentences as a basis for concept formation

A concept-formation study was run using sets of sentences in eight different syntactic patterns as target categories. These were based on all possible combinations of voice (active or passive), mood (declarative or interrogative), and modality (affirmative or negative). Subjects were 32 senior high school students who participated as volunteers in the computer-controlled experiment. Subjects were able to categorize sentences based solely on sentence types rather than semantic content, but an analysis of the errors committed in the course of learning showed that it was the semantic significance of different types rather than pattern differences as such to which a subject responded. The implications of this for grammatical formulations and the interpretation of psychological research were discussed.     

Syntactic processing of Hebrew sentences in normal and dyslexic readers: electrophysiological evidence

The authors examined differences in brain activity as measured by amplitudes and latencies of event-related potential (ERP) components in Hebrew-speaking adult dyslexic and normal readers. The participants were measured while processing words' syntactic functions during reading of sentences with subject-verb-object syntactic order. The results suggested that among dyslexic and normal readers, N100 and P300 ERP components were sensitive to certain constituents of syntactic analysis for target words in accordance with their grammatical roles. The findings further demonstrated significant differences in ERP measures between dyslexic and normal readers. Compared with normal readers, dyslexic readers exhibited consistently higher amplitudes and longer latencies in both ERP components for the subject of the sentence. Significant, though less consistent, ERP variations were observed for other sentence elements. In addition, dyslexic readers differed from normal readers in their processing strategies. For normal readers, the verb-oriented, morphologically based strategy was found to be the most efficient for sentence processing in Hebrew, whereas the dyslexic readers demonstrated a more primitive mode of identification of words' grammatical roles, namely, the word-order strategy. The results support the hypothesis that there is a syntactic processing "weakness" in dyslexics.     

Quantitative Standards for Absolute Linguistic Universals

Absolute linguistic universals are often justified by cross‐linguistic analysis: If all observed languages exhibit a property, the property is taken to be a likely universal, perhaps specified in the cognitive or linguistic systems of language learners and users. In many cases, these patterns are then taken to motivate linguistic theory. Here, we show that cross‐linguistic analysis will very rarely be able to statistically justify absolute, inviolable patterns in language. We formalize two statistical methods—frequentist and Bayesian—and show that in both it is possible to find strict linguistic universals, but that the numbers of independent languages necessary to do so is generally unachievable. This suggests that methods other than typological statistics are necessary to establish absolute properties of human language, and thus that many of the purported universals in linguistics have not received sufficient empirical justification.     

Lexically restricted utterances in Russian, german, and english child-directed speech

This study investigates the child-directed speech (CDS) of four Russian-, six German, and six English-speaking mothers to their 2-year-old children. Typologically Russian has considerably less restricted word order than either German or English, with German showing more word-order variants than English. This could lead to the prediction that the lexical restrictiveness previously found in the initial strings of English CDS by Cameron-Faulkner, Lieven, and Tomasello (2003 ) would not be found in Russian or German CDS. However, despite differences between the three corpora that clearly derive from typological differences between the languages, the most significant finding of this study is a high degree of lexical restrictiveness at the beginnings of CDS utterances in all three languages.     

Syntactic Processing of Hebrew Sentences in Normal and Dyslexic Readers: Electrophysiological Evidence

The authors examined differences in brain activity as measured by amplitudes and latencies of event-related potential (ERP) components in Hebrew-speaking adult dyslexic and normal readers. The participants were measured while processing words' syntactic functions during reading of sentences with subject-verb-object syntactic order. The results suggested that among dyslexic and normal readers, N100 and P300 ERP components were sensitive to certain constituents of syntactic analysis for target words in accordance with their grammatical roles. The findings further demonstrated significant differences in ERP measures between dyslexic and normal readers. Compared with normal readers, dyslexic readers exhibited consistently higher amplitudes and longer latencies in both ERP components for the subject of the sentence. Significant, though less consistent, ERP variations were observed for other sentence elements. In addition, dyslexic readers differed from normal readers in their processing strategies. For normal readers, the verb-oriented, morphologically based strategy was found to be the most efficient for sentence processing in Hebrew, whereas the dyslexic readers demonstrated a more primitive mode of identification of words' grammatical roles, namely, the word-order strategy. The results support the hypothesis that there is a syntactic processing “weakness” in dyslexics.     

Processing typology and why psychologists need to know about it

This paper illustrates an interdisciplinary research program based on cross-linguistic comparison that is of relevance for psychologists working on language processing, so-called “processing typology” [Hawkins, J. A. (1994). A performance theory of order and constituency. Cambridge: Cambridge University Press; (2004). Efficiency and complexity in grammars. Oxford: Oxford University Press]. Its most original feature is the hypothesis that patterns and preferences found in performance in languages with several structures of a given type (e.g. preferences among alternative word orders) are the same patterns and preferences one finds across languages in the fixed conventions of grammars that permit less variation (i.e. in fixed word orders). Data supporting this “performance-grammar correspondence hypothesis” are summarized. One of its consequences is that principles of performance can be used to make predictions for patterns of grammatical variation, while preferences in grammars become relevant for the testing of psycholinguistic ideas. Two proposed principles of ordering in performance, in terms of “end weight” and “memory cost”, are criticized on the basis of cross-linguistic data. Both predict an asymmetry in ordering, whereby some category A precedes B. But end weight is not a valid cross-linguistic asymmetry, and memory cost cannot explain certain asymmetries for which it has been invoked when different language types are considered. The paper argues for greater mutual awareness between processing theorists and language typologists, for more consideration of non-European grammars and language types in psycholinguistics, and for a greater appeal to processing in the explanation of typological variation.     

Language Reflects “Core” Cognition: A New Theory About the Origin of Cross‐Linguistic Regularities

The underlying structures that are common to the world's languages bear an intriguing connection with early emerging forms of “core knowledge” (Spelke & Kinzler, 2007), which are frequently studied by infant researchers. In particular, grammatical systems often incorporate distinctions (e.g., the mass/count distinction) that reflect those made in core knowledge (e.g., the non‐verbal distinction between an object and a substance). Here, I argue that this connection occurs because non‐verbal core knowledge systematically biases processes of language evolution. This account potentially explains a wide range of cross‐linguistic grammatical phenomena that currently lack an adequate explanation. Second, I suggest that developmental researchers and cognitive scientists interested in (non‐verbal) knowledge representation can exploit this connection to language by using observations about cross‐linguistic grammatical tendencies to inspire hypotheses about core knowledge.     

Processing relative clauses in Chinese

This paper reports results from a self-paced reading study in Chinese that demonstrates that object-extracted relative clause structures are less complex than corresponding subject-extracted structures. These results contrast with results from processing other Subject-Verb-Object languages like English, in which object-extracted structures are more complex than subject-extracted structures. A key word-order difference between Chinese and other Subject-Verb-Object languages is that Chinese relative clauses precede their head nouns. Because of this word order difference, the results follow from a resource-based theory of sentence complexity, according to which there is a storage cost associated with predicting syntactic heads in order to form a grammatical sentence. The results are also consistent with a theory according to which people have less difficulty processing embedded clauses whose word order matches the word order in main clauses. Some corpus analyses of Chinese texts provide results that constrain the classes of possible frequency-based theories. Critically, these results demonstrate that there is nothing intrinsically easy about extracting from subject position: depending on the word order in the main clause and in a relative clause, extraction from object position can be easier to process in some circumstances.