Persistent stress 'deafness': the case of French learners of Spanish

Previous research by Dupoux et al. [Dupoux, E., Pallier, C., Sebastián, N., & Mehler, J. (1997). A destressing "deafness" in French? Journal of Memory Language 36, 406-421; Dupoux, E., Peperkamp, S., & Sebastián-Gallés (2001). A robust method to study stress' deafness. Journal of the Acoustical Society of America 110, 1608-1618.] found that French speakers, as opposed to Spanish ones, are impaired in discrimination tasks with stimuli that vary only in the position of stress. However, what was called stress 'deafness' was only found in tasks that used high phonetic variability and memory load, not in cognitively less demanding tasks such as single token AX discrimination. This raised the possibility that instead of a perceptual problem, monolingual French speakers might simply lack a metalinguistic representation of contrastive stress, which would impair them in memory tasks. We examined a sample of 39 native speakers of French who underwent formal teaching of Spanish after age 10, and varied in degree of practice in this language. Using a sequence recall task, we observed in all our groups of late learners of Spanish the same impairment in short-term memory encoding of stress contrasts that was previously found in French monolinguals. Furthermore, using a speeded lexical decision task with word-nonword minimal pairs that differ only in the position of stress, we found that all late learners had much difficulty in the use of stress to access the lexicon. Our results show that stress 'deafness' is better interpreted as a lasting processing problem resulting from the impossibility for French speakers to encode contrastive stress in their phonological representations. This affects their memory encoding as well as their lexical access in on-line tasks. The generality of such a persistent suprasegmental 'deafness' is discussed in relation to current findings and models on the perception of non-native phonological contrasts.     

The influence of personality and anxiety on the oral performance of Japanese speakers of English

This study investigated the relationship between personality and anxiety characteristics of Japanese students and their oral performance in English. The participants were 73 native‐speakers of Japanese who were studying English at various language schools in New Zealand. They were administered the Maudsley Personality Inventory, the Spielberger State Anxiety Inventory, and a story‐retelling task which was scored in terms of oral fluency, accuracy, complexity, and global impression. Significant correlations were found between extraversion and global impression scores, and state anxiety and clause accuracy scores. These findings suggest that participants who were more extraverted produced better global impressions during their oral performance, and those who were experiencing higher levels of state anxiety made more errors in their spoken use of clauses. Copyright © 2004 John Wiley & Sons, Ltd.     

Mother versus stranger: a triadic situation of imitation at the end of the first year of life

This study presents two experiments investigating 8‐ and 12‐month‐old infants' imitative behaviour. Seventy‐two 8‐month‐olds and seventy‐two 12‐month‐olds were observed in a triadic situation which included their mother and a stranger. Depending on the condition, either the mother or the stranger acted as the demonstrator and either stayed close or withdrew after the demonstration, during the response period. In addition to imitative acts, visual exploration and smiles addressed, respectively, to each partner were computed. Results showed that at both ages, neither the familiarity nor the position of the partner has an effect on the number of target gestures that are imitated. At 12 months, infants looked and smiled more at the stranger when he demonstrated target actions but no difference was found when the mother acted as demonstrator. Moreover, 12‐month‐old infants looked more at the demonstrating partner immediately after their first imitation. At 8 months, infants paid more attention to the stranger in all conditions except when the mother performed the target actions and moved away, a pattern that suggests a referencing to the mother. Results from the gaze and smile variables suggest that with age different motivations (social contact, exploration of objects) induce imitation. Copyright © 2003 John Wiley & Sons, Ltd.     

The acquisition of allophonic rules: statistical learning with linguistic constraints

Phonological rules relate surface phonetic word forms to abstract underlying forms that are stored in the lexicon. Infants must thus acquire these rules in order to infer the abstract representation of words. We implement a statistical learning algorithm for the acquisition of one type of rule, namely allophony, which introduces context-sensitive phonetic variants of phonemes. This algorithm is based on the observation that different realizations of a single phoneme typically do not appear in the same contexts (ideally, they have complementary distributions). In particular, it measures the discrepancies in context probabilities for each pair of phonetic segments. In Experiment 1, we test the algorithm's performances on a pseudo-language and show that it is robust to statistical noise due to sampling and coding errors, and to non-systematic rule application. In Experiment 2, we show that a natural corpus of semiphonetically transcribed child-directed speech in French presents a very large number of near-complementary distributions that do not correspond to existing allophonic rules. These spurious allophonic rules can be eliminated by a linguistically motivated filtering mechanism based on a phonetic representation of segments. We discuss the role of a priori linguistic knowledge in the statistical learning of phonology.     

Identifying lesions on structural brain images--validation of the method and application to neuropsychological patients

The study of neuropsychological disorders has been greatly facilitated by the localization of brain lesions on MRI scans. Current popular approaches for the assessment of MRI brain scans mostly depend on the successful segmentation of the brain into grey and white matter. These methods cannot be used effectively with large lesions because lesions usually impair segmentation. We propose a novel, fully automated approach for the delineation of brain lesions on MR scans. This method involves comparing a skull stripped, smoothed, unsegmented T1 images to a control group using the general linear model. We tested this method by using images with simulated lesions of different sizes and images containing real lesions from patients with language deficits. We also tested how varying the size of the Gaussian smoothing kernel affects detection. The simulation was informed by findings of a lesion morphological study also presented here. The proposed method detected simulated lesions effectively in the range of 30--90%相似文献   

CANTAB explicit memory is less impaired in addicted schizophrenia patients

It has been suggested that in order to sustain the lifestyle of substance abuse, addicted schizophrenia patients would have less negative symptoms, better social skills, and less cognitive impairments. Mounting evidence supports the first two assumptions, but data lack regarding cognition in dual diagnosis schizophrenia. Seventy-six schizophrenia outpatients (DSM-IV) were divided into two groups: with (n = 44) and without (n = 32) a substance use disorder. Motor speed and visuo-spatial explicit memory were investigated using CANTAB. As expected, dual diagnosis patients showed a better cognitive performance. Our results suggest either that substance abuse relieves the cognitive deficits of schizophrenia or that the patients with less cognitive deficits are more prone to substance abuse.     

Subliminal speech priming

We present a novel subliminal priming technique that operates in the auditory modality. Masking is achieved by hiding a spoken word within a stream of time-compressed speechlike sounds with similar spectral characteristics. Participants were unable to consciously identify the hidden words, yet reliable repetition priming was found. This effect was unaffected by a change in the speaker's voice and remained restricted to lexical processing. The results show that the speech modality, like the written modality, involves the automatic extraction of abstract word-form representations that do not include nonlinguistic details. In both cases, priming operates at the level of discrete and abstract lexical entries and is little influenced by overlap in form or semantics.     

What face inversion does to infants' counting abilities

Infants younger than 1 year do not correctly count the number of objects in a scene by using differences among their properties, unless these differences cross the broad category boundaries separating humans, animals, and artifacts. Here we show that face orientation influences whether 10- and 12-month-old infants count correctly or incorrectly. When infants saw two puppets appearing and disappearing behind an occluder successively and had no cues for numerosity other than differences among the puppets' properties, they correctly counted two puppets if one had an upright face and one an upside-down face. However, when the same puppets were both shown with faces upright, infants failed the task. Overall, this pattern of success and failure closely parallels the pattern of brain activations registered when adults and infants watch objects characterized by the same property contrasts.