Over the course of the first year of life, infants develop from being generalized listeners, capable of discriminating both native and non-native speech contrasts, into specialized listeners whose discrimination patterns closely reflect the phonetic system of the native language(s). Recent work by Maye, Werker and Gerken (2002) has proposed a statistical account for this phenomenon, showing that infants may lose the ability to discriminate some foreign language contrasts on the basis of their sensitivity to the statistical distribution of sounds in the input language. In this paper we examine the process of enhancement in infant speech perception, whereby initially difficult phonetic contrasts become better discriminated when they define two categories that serve a functional role in the native language. In particular, we demonstrate that exposure to a bimodal statistical distribution in 8-month-old infants ’ phonetic input can lead to increased discrimination of difficult contrasts. In addition, this exposure also facilitates discrimination of an unfamiliar contrast sharing the same phonetic feature as the contrast presented during familiarization, suggesting that infants extract acoustic/phonetic information that is invariant across an abstract featural representation.

& Investigating the degree of similarity between infants ’ and adults ’ representation of speech is critical to our understanding of infants ’ ability to acquire language. Phoneme perception plays a crucial role in language processing, and numerous behavioral studies have demonstrated similar capacities in infants and adults, but are these subserved by the same neural substrates or networks? In this article, we review event-related potential (ERP) results obtained in infants during phoneme discrimination tasks and compare them to results from the adult literature. The striking similarities observed both in behavior and ERPs between initial and mature stages suggest a continuity in processing and neural structure. We argue that infants have access at the beginning of life to phonemic representations, which are modified without training or implicit instruction, but

Previous research has shown that native speakers of French, as opposed to those of Spanish, exhibit stress `deafness', i.e. have difficulties distinguishing stress contrasts. In French, stress is non-contrastive, while in Spanish, stress is used to make lexical distinctions. We examine three other languages with non-contrastive stress, Finnish, Hungarian and Polish. In two experiments with a short-term memory sequence repetition task, we find that speakers of Finnish and Hungarian are like French speakers (i.e. exhibit stress `deafness'), but not those of Polish. We interpret these findings in the light of an acquisition framework, that states that infants decide whether or not to keep stress in their phonological representation during the first two years of life, based on information extractable from utterance edges. In particular, we argue that Polish infants, unlike French, Finnish and Hungarian ones, cannot extract the stress regularity of their language on the basis of what they have already learned. As a consequence, they keep stress in their phonological representation, and as adults, they do not have difficulties in distinguishing stress contrasts.

The sound pattern of the language(s) we have heard as infants affects the way in which we perceive linguistic sounds as adults. Typically, some foreign sounds are very difficult to perceive accurately, even after extensive training. For instance, native speakers of French have troubles distinguishing foreign words that differ only in the position of main stress, French being a language in which stress is not contrastive.

itudinal studies in children have documented the process of attrition over several weeks or months. Nicoladis & Grabois (2002) studied the simultaneous loss of Cantonese and acquisition of English in a young Chinese girl adopted by an English-speaking family in Canada, at age 17 months. The interactions with native Cantonese speakers over the three months following the child's arrival in Canada, revealed a rapid loss in both production and comprehension of this language by the child. Kaufman & Aronoff (1991) studied a native Hebrewspeaking child having immigrated to the United States with her family at age 2 ;6. This child, contrary to the adoptees in the present study and the Chinese girl mentioned above, continued being exposed to her L1 while acquiring L2 in the school environment. Yet, despite this continued exposure, attrition of L1 (lexical and morphological) was once again observed after only a few months in the country of immigration. Turian & Altenberg's (1991) study focussed

presentations; language dominance; speed--accuracy tradeoff; semantic retrieval. How are lexical and conceptual information represented in memory for speakers of more than one language? Early approaches to this issue focused on the logical extremes, seeking to determine whether the languages of multilingual speakers are represented in a common store or in separate stores (see, McCormack, 1977). More recently, a consensus has emerged that languages have functionally separate stores for form-based, lexical (phonological and orthographic) representations but share a common set of conceptual representations (e.g., Durgunoglu & Roediger, 1987; Potter et al., 1984; Snodgrass, 1984; but see Van Heuven, Dijkstra, & Grainger, 1998). This hierarchical model of bilingual memory can be partly motivated by monolingual research indicating that linguistic information is represented in separable levels (Smith, 1997). However, its primary strength derives from its ability to provide a systematic acco

An ubiquitous phenomenon in psychology is the `repetition effect': a repeated stimulus is processed better on the second occurrence than on the first. Yet, what counts as a repetition? When a spoken word is repeated, is it the acoustic shape or the linguistic type that matters? In the present study, we contrasted the contribution of acoustic and phonological features by using participants with different linguistic backgrounds: they came from two populations sharing a common vocabulary (Catalan) yet possessing different phonemic systems [1]. They performed a lexical decision task with lists containing words that were repeated verbatim, as well as words that were repeated with one phonetic feature changed. The feature changes were phonemic, i.e. linguistically relevant, for one population, but not for the other. The results revealed that the repetition effect was modulated by linguistic, not acoustic, similarity: it depended on the subjects' phonemic system. 1. INTRODUCTION Are word for...

Under what format(s) are spoken words memorized by the brain? Are word forms stored as abstract phonological representations? Or rather, are they stored as detailed acoustic-phonetic representations? (For example as a set of acoustic exemplars associated with each word). We present a series of experiments whose results point to the existence of prelexical phonological processes in word recognition and suggest that spoken words are accessed using a phonological code. 1. INTRODUCTION Linguistics makes a strong case for the psychological reality of phonological representations. It is important to assess how and when phonological representations are used by the brain. Some have argued that phonological representations may be used in speech production but not in speech perception [1, 2, 3]. They propose, instead, that word recognition involves a "direct" mapping from an acoustic representation of the input to the lexical representations. The series of experiments presented in this paper a...

this paper, we focus on the effect of age of acquisition on the neuronal substrate of L2. By comparing the results of this study with the results of the previous investigations, we may be able to evaluate the role of proficiency per se.We report two studies with subjects who have learned L2 to a high degree of proficiency, but who differ in the age of acquisition of the second language. In the first study we investigated nine adult male Italian subjects who learned English after the age of 10 years, but who, nevertheless, achieved excellent English speaking skills (the HPLA---high proficiency, late acquisition---group). In the second study we investigated 12 Spanish-born subjects who learned Spanish and Catalan very early in life and spoke both languages for most of their lives (the HPEA---high proficiency, early acquisition---group). In both studies we explored the cortical activation while volunteers listened to stories in L1 and L2. The data were compared with the results reported by Perani et al. (1996) on low proficiency, late acquisition (LPLA) subjects

Do the neural circuits that subserve language acquisition lose plasticity as they become tuned to the maternal language? We tested adult subjects born in Korea and adopted by French families in childhood; they have become fluent in their second language and report no conscious recollection of their native language. In behavioral tests assessing their memory for Korean, we found that they do not perform better than a control group of native French subjects who have never been exposed to Korean. We also used event-related fMRI to monitor cortical activations while the Korean adoptees and native French listened to sentences spoken in the Korean, French, and in other unknown foreign languages. The adopted subjects did not show any specific activations to Korean stimuli relative to unknown languages.