Rapid Learning of Morphological Paradigms.

Rapid Learning of Morphological Paradigms Sara Finley (sara.finley@waldorf.edu) Department of Psychology, Waldorf College Forest City, IA, 50436, USA Elizabeth Wiemers (wiemerse@net.elmhurst.edu) Department of Psychology, Elmhurst College Elmhurst, IL, 60126, USA This study specifically looks at learning of morphologically complex words. Morphemes are parts of words that do not break down into smaller segments with meanings. For example, the word flying contains two morphemes: fly and –ing. Morphology plays an important role in language learning (as well as in learning linguistic categories) because morphology involves both the form of the morpheme (e.g., -ing) as well as its meaning (i.e., progressive). Because morphological forms are often bound – attached to the stems of each word in the category, learners must be able to recognize morphemes within complex words. In order to learn the morphology of one’s language, the learner must be able to separate words in terms of their morphological parts. This ability is referred to as morpheme segmentation. Because all morphemes involve form and meaning, there is a question as to when both aspects of the morpheme are learned. Given that infants are exposed to complex words in speech before they know the meaning of many words, it is likely that infants are able to segment morphological information without semantics. Studies have shown that by 15 months, infants can use distributional cues to learn non- adjacent dependencies, which are necessary for learning syntactic categories (Gomez & Maye, 2005), and by 18 months, can begin to acquire categories (Mintz, Newport, & Bever, 2002). Gomez and Gerken (2000) suggest that some learning of categories occurs at the very earliest stages of life. These studies suggest that morpheme segmentation can occur without knowledge of the specific meaning of the words. In addition, these results also suggest the possibility that early learners are equipped with biases to learn linguistic systems using distributional cues. Because languages tend to show broad similarities with respect to the nature of complex morphological rules, it is possible that languages evolved to accommodate biases within the learner. The nature of learning biases in young infants raises the question as to why there are differences between child and adult language learners. Any theory of learning biases, innate or otherwise, must explain how biases change (and remain the same) over time, in order to explain why children and adults show differences in language learning strategies (Newport, 1990). One hypothesis is that adults have lost the abilities for acquisition that children have (MacWhinney, 1983), but in some cases of artificial language learning, adults outperform children. Specifically, Braine, Brody, and Brooks (1990) showed higher rates of learning for adults Abstract The present study presents a novel paradigm for testing the ability for adults to rapidly learn novel morphological categories in the wake of irrelevant information: specifically number markings intermixed with irrelevant gender cues. Using an artificial language learning paradigm, participants were exposed to picture-sound pairs in which pictures of animals varied by number (singular, dual and plural), but with irrelevant gender information intermixed with the exposure items (masculine, feminine and neuter). Auditory stimuli were presented in CVCVCV forms (e.g., [zovabu]) in which the first two syllables denoted the animal (e.g., [zova] for snail) and the final syllable denoted number. (e.g., [bu] for single). Results revealed that participants were able to learn which category the suffix endings referred to, based on a two-alternative forced-choice generalization task. Implications for the learning of complex paradigms are discussed. Keywords: statistical learning, number, morphology. Introduction Languages are governed by complex sets of rules in which sentences are formed through a systematic combination of words. The rule-governed nature of sentences relies heavily on the use of morphological rules and syntactic categories. Words of the same syntactic categories (e.g., nouns and verbs) share similarities beyond meaning. For example, while verbs typically describe actions, in English verbs frequently follow a noun and precede a prepositional phrase (as in The dog sat on the carpet). In addition, syntactic categories share morphological properties, such as tense, gender and number. These morphological indicators are often present as prefixes or suffixes. The specific phonological form of these morphemes appears to be arbitrary in many languages, as in the use of /-s/ as plural in English. However, there is some evidence that languages with complex systems of gender and number morphology such as French, German, and Hebrew may show signs of systematicity within subcategories (Brooks, Braine, Catalano, and Brody, 1993). In this paper we explore how adults are able to learn complex systems of morphology, and whether learners are sensitive to differences in the arbitrariness of morphological patterns.