Individual differences in attention control and the processing of phonological contrasts in a second language.

This study investigated attention control in L2 phonological processing from a cognitive individual differences perspective, to determine its role in predicting phonological acquisition in adult L2 learning. Participants were 21 L1-Spanish learners of English, and 19 L1-English learners of Spanish. Attention control was measured through a novel speech-based attention-switching task. Phonological processing was assessed through a speeded ABX categorization task (perception) and a delayed sentence repetition task (production). Correlational analyses indicated that learners with more efficient attention switching skill and faster speed in correctly identifying the target phonetic features in the speech dimension under focus could perceptually discriminate L2 vowels at higher processing speed, but not at higher accuracy rates. Thus, attentional flexibility provided a processing advantage for difficult L2 contrasts but did not predict the extent to which precise representations for the target L2 vowels had been established. However, attention control was related to L2 learners' ability to distinguish the contrasting L2 vowels in production. In addition, L2 learners' accuracy in perceptually distinguishing between two contrasting vowels was significantly related to how much of a quality distinction between them they could make in production.

Vocabulary Size Is a Key Factor in Predicting Second Language Lexical Encoding Accuracy.

This study investigates the relationship between the accuracy of second language lexical representations and perception, phonological short-term memory, inhibitory control, attention control, and second language vocabulary size. English-speaking learners of Spanish were tested on their lexical encoding of the Spanish /ɾ-r/, /ɾ-d/, /r-d/, and /f-p/ contrasts through a lexical decision task. Perception ability was measured with an oddity task, phonological short-term memory with a serial non-word recognition task, attention control with a flanker task, inhibitory control with a retrieval-induced inhibition task, and vocabulary size with the X_Lex vocabulary test. Results revealed that differences in perception performance, inhibitory control, and attention control were not related to differences in lexical encoding accuracy. Phonological short-term memory was a significant factor, but only for the /r-ɾ/ contrast. This suggests that when representations contain sounds that are differentiated along a dimension not used in the native language, learners with higher phonological short-term memory have an advantage because they are better able to hold the relevant phonetic details in memory long enough to be transferred to long-term representations. Second language vocabulary size predicted lexical encoding across three of the four contrasts, such that a larger vocabulary predicted greater accuracy. This is likely because the acquisition of more phonologically similar words forces learners' phonological systems to create more detailed representations in order for such words to be differentiated. Overall, this study suggests that vocabulary size in the second language is the most important factor in the accuracy of lexical representations.

The Hoosier Vocal Emotions Corpus: A validated set of North American English pseudo-words for evaluating emotion processing.

This article presents the development of the "Hoosier Vocal Emotions Corpus," a stimulus set of recorded pseudo-words based on the pronunciation rules of English. The corpus contains 73 controlled audio pseudo-words uttered by two actresses in five different emotions (i.e., happiness, sadness, fear, anger, and disgust) and in a neutral tone, yielding 1,763 audio files. In this article, we describe the corpus as well as a validation study of the pseudo-words. A total of 96 native English speakers completed a forced choice emotion identification task. All emotions were recognized better than chance overall, with substantial variability among the different tokens. All of the recordings, including the ambiguous stimuli, are made freely available, and the recognition rates and the full confusion matrices for each stimulus are provided in order to assist researchers and clinicians in the selection of stimuli. The corpus has unique characteristics that can be useful for experimental paradigms that require controlled stimuli (e.g., electroencephalographic or fMRI studies). Stimuli from this corpus could be used by researchers and clinicians to answer a variety of questions, including investigations of emotion processing in individuals with certain temperamental or behavioral characteristics associated with difficulties in emotion recognition (e.g., individuals with psychopathic traits); in bilingual individuals or nonnative English speakers; in patients with aphasia, schizophrenia, or other mental health disorders (e.g., depression); or in training automatic emotion recognition algorithms. The Hoosier Vocal Emotions Corpus is available at https://psycholinguistics.indiana.edu/hoosiervocalemotions.htm.

Diminished Neural Responses to Emotionally Valenced Facial Stimuli: A Potential Biomarker for Unemotional Traits in Early Childhood.

Callous-unemotional (CU) traits are characterized by deficits in guilt/empathy, shallow affect, and the callous and manipulative use of others. Individuals showing CU traits have increased risk for behavior problems and reduced responses to displays of distress in others. To explore how deficits in emotion-processing are associated with CU traits, the current study examined the association between callous-unemotionality and a neural index of facial emotion processing, using the event-related potential technique in a group of 3-5 year olds. Children viewed a series of static emotional faces, depicting either fear or happiness, while electroencephalography data were collected. The N170 component, thought to index the neural processes associated with face perception, was examined along with CU traits. Findings suggest that the unemotional dimension of CU traits is associated with diminished emotion-processing responses to fearful faces. Reduced neural responses to facial depictions of fear could be a biomarker for unemotional traits in early childhood.

The Effect of Orthography on the Lexical Encoding of Palatalized Consonants in L2 Russian.

The current study investigated the potential facilitative or inhibiting effects of orthography on the lexical encoding of palatalized consonants in L2 Russian. We hypothesized that learners with stable knowledge of orthographic and metalinguistic representations of palatalized consonants would display more accurate lexical encoding of the plain/palatalized contrast. The participants of the study were 40 American learners of Russian. Ten Russian native speakers served as a control group. The materials of the study comprised 20 real words, familiar to the participants, with target coronal consonants alternating in word-final and intervocalic positions. The participants performed three tasks: written picture naming, metalinguistic, and auditory word-picture matching. Results showed that learners were not entirely familiar with the grapheme-phoneme correspondences in L2 Russian. Even though they spelled almost all of these familiar Russian words accurately, they were able to identify the plain/palatalized status of the target consonants in these words with about 80% accuracy on a metalinguistic task. The effect of orthography on the lexical encoding was found to be dependent on the syllable position of the target consonants. In intervocalic position, learners erroneously relied on vowels following the target consonants rather than the consonants themselves to encode words with plain/palatalized consonants. In word-final position, although learners possessed the orthographic and metalinguistic knowledge of the difference in the palatalization status of the target consonants-and hence had established some aspects of the lexical representations for the words-those representations appeared to lack in phonological granularity and detail, perhaps due to the lack of perceptual salience.

Reduced neural responses to vocal fear: a potential biomarker for callous-uncaring traits in early childhood.

OBJECTIVE: Callous-unemotional (CU) traits are characterized by a lack of guilt and empathy, and low responsiveness to distress and fear in others. Children with CU traits are at-risk for engaging in early and persistent conduct problems. Individuals showing CU traits have been shown to have reduced neural responses to others' distress (e.g., fear). However, the neural components of distress responses in children with CU traits have not been investigated in early childhood. In the current study, we examined neural responses that underlie the processing of emotionally valenced vocal stimuli using the event-related potential technique in a group of preschoolers. METHOD: Participants between 2 and 5 years old took part in an auditory oddball task containing English-based pseudowords spoken with either a fearful, happy, or a neutral prosody while electroencephalography data were collected. The mismatch negativity (MMN) component, an index of the automatic detection of deviant stimuli within a series of stimuli, was examined in association with two dimensions of CU traits (i.e., callousness-uncaring and unemotional dimensions) reported by primary caregivers. RESULTS: Findings suggest that the callousness-uncaring dimension of CU traits in early childhood is associated with reduced responses to fearful vocal stimuli. CONCLUSIONS: Reduced neural responses to vocal fear could be a biomarker for callous-uncaring traits in early childhood. These findings are relevant for clinicians and researchers attempting to identify risk factors for early callous-uncaring traits.

Modality-specific processing precedes amodal linguistic processing during L2 sign language acquisition: A longitudinal study.

The present study tracked activation pattern differences in response to sign language processing by late hearing second language learners of American Sign Language. Learners were scanned before the start of their language courses. They were scanned again after their first semester of instruction and their second, for a total of 10 months of instruction. The study aimed to characterize modality-specific to modality-general processing throughout the acquisition of sign language. Results indicated that before the acquisition of sign language, neural substrates related to modality-specific processing were present. After approximately 45 h of instruction, the learners transitioned into processing signs on a phonological basis (e.g., supramarginal gyrus, putamen). After one more semester of input, learners transitioned once more to a lexico-semantic processing stage (e.g., left inferior frontal gyrus) at which language control mechanisms (e.g., left caudate, cingulate gyrus) were activated. During these transitional steps right hemispheric recruitment was observed, with increasing left-lateralization, which is similar to other native signers and L2 learners of spoken language; however, specialization for sign language processing with activation in the inferior parietal lobule (i.e., angular gyrus), even for late learners, was observed. As such, the present study is the first to track L2 acquisition of sign language learners in order to characterize modality-independent and modality-specific mechanisms for bilingual language processing.

Bimodal bilingualism as multisensory training?: Evidence for improved audiovisual speech perception after sign language exposure.

The aim of the present study was to characterize effects of learning a sign language on the processing of a spoken language. Specifically, audiovisual phoneme comprehension was assessed before and after 13 weeks of sign language exposure. L2 ASL learners performed this task in the fMRI scanner. Results indicated that L2 American Sign Language (ASL) learners' behavioral classification of the speech sounds improved with time compared to hearing nonsigners. Results indicated increased activation in the supramarginal gyrus (SMG) after sign language exposure, which suggests concomitant increased phonological processing of speech. A multiple regression analysis indicated that learner's rating on co-sign speech use and lipreading ability was correlated with SMG activation. This pattern of results indicates that the increased use of mouthing and possibly lipreading during sign language acquisition may concurrently improve audiovisual speech processing in budding hearing bimodal bilinguals.

Modality-independent neural mechanisms for novel phonetic processing.

The present study investigates whether the inferior frontal gyrus is activated for phonetic segmentation of both speech and sign. Early adult second language learners of Spanish and American Sign Language at the very beginning of instruction were tested on their ability to classify lexical items in each language based on their phonetic categories (i.e., initial segments or location parameter, respectively). Conjunction analyses indicated that left-lateralized inferior frontal gyrus (IFG), superior parietal lobule (SPL), and precuneus were activated for both languages. Common activation in the left IFG suggests a modality-independent mechanism for phonetic segmentation. Additionally, common activation in parietal regions suggests spatial preprocessing of audiovisual and manuovisual information for subsequent frontal recoding and mapping. Taken together, we propose that this frontoparietal network is involved in domain-general segmentation of either acoustic or visual signal that is important to novel phonetic segmentation.

The role of the striatum in phonological processing: evidence from early stages of Huntington's disease.

The linguistic role of subcortical structures such as the striatum is still controversial. According to the claim that language processing is subdivided into a lexical memory store and a computational rule system (Pinker, 1999) several studies on word morphology (e.g., Ullman et al., 1997) and on syntax (e.g., Teichmann et al., 2005) have suggested that the striatum is specifically dedicated to the latter component. However, little is known about whether the striatum is involved in phonological operations and whether its role in linguistic rule application generalizes to phonological processing. We investigated this issue by assessing perceptual compensation for assimilation rules in a model of striatal disorders, namely in the early stages of Huntington's disease (HD). In Experiment 1 we used a same-different task with isolated words to evaluate whether phoneme perception is intact in HD. In Experiment 2 a word detection task in phrasal contexts allowed for assessing both phoneme perception and perceptual compensation for the French regressive assimilation rule. Results showed that HD patients have normal performance with both phoneme perception in isolated words and regressive assimilation rules. However, in phrasal contexts they display reduced abilities of phoneme discrimination. These findings challenge the striatum-rule claim and suggest a more fine-grained function of striatal structures in linguistic rule processing. Alternative explanatory frameworks of the striatum-language link are discussed.