Sensitivity of human auditory cortex to rapid frequency modulation revealed by multivariate representational similarity analysis.

Functional Magnetic Resonance Imaging (fMRI) was used to investigate the extent, magnitude, and pattern of brain activity in response to rapid frequency-modulated sounds. We examined this by manipulating the direction (rise vs. fall) and the rate (fast vs. slow) of the apparent pitch of iterated rippled noise (IRN) bursts. Acoustic parameters were selected to capture features used in phoneme contrasts, however the stimuli themselves were not perceived as speech per se. Participants were scanned as they passively listened to sounds in an event-related paradigm. Univariate analyses revealed a greater level and extent of activation in bilateral auditory cortex in response to frequency-modulated sweeps compared to steady-state sounds. This effect was stronger in the left hemisphere. However, no regions showed selectivity for either rate or direction of frequency modulation. In contrast, multivoxel pattern analysis (MVPA) revealed feature-specific encoding for direction of modulation in auditory cortex bilaterally. Moreover, this effect was strongest when analyses were restricted to anatomical regions lying outside Heschl\u27s gyrus. We found no support for feature-specific encoding of frequency modulation rate. Differential findings of modulation rate and direction of modulation are discussed with respect to their relevance to phonetic discrimination

Eyetracking of coarticulatory cue responses in children and adults

Prior work suggests listeners are sensitive to coarticulatory cues during spoken word recognition; however, little is known about how this ability develops in children. In the present study, children and adults listened to words containing congruent and incongruent coarticulatory cues while looking at a two-picture display. We manipulated the congruency of the auditory-coarticulatory information such that the initial phoneme of the auditory cue matched the target, or contained an incongruent initial phoneme that instead matched the distractor picture. Accordingly, we observed both slower rates of looks to the target and higher rates of looks to the distractor on incongruent trials, indicating that both children and adults were sensitive to coarticulatory congruency. These findings suggest that children maintain detailed phonological representations of words, and may use coarticulatory information to facilitate spoken word recognition

Specific language impairment in children: Phonology, semantics and the English past tense

ABSTRACT-Theories of specific language impairment (SLI) in children turn on whether this deficit stems from a grammarspecific impairment or a more general speech-processing deficit. This issue parallels a more general question in cognitive neuroscience concerning the brain bases of linguistic rules. This more general debate frequently focuses on past-tense verbs, specifically, whether regular verbs (bake-baked) are encoded as rules, and whether irregular forms (take-took) are processed differently. Children with SLI have difficulties with past tenses, so SLI could represent an impairment to rules. An alternative theory explains past-tense deficits in SLI as resulting from a phonological deficit. Evidence for this theory has been obtained from connectionist models of past-tense impairments and from behavioral studies of language-and reading-impaired children. The data suggest that SLI is not an impairment to linguistic rules, that past-tense impairments can be explained as resulting from a perceptual deficit, and that a single processing mechanism is ideally suited to account for these children's difficulties. KEYWORDS-specific language impairment; connectionism; English past tense; speech perception A key question in cognitive neuroscience concerns the neural mechanism by which humans encode the rules of language. The English past tense represents an interesting case of rulelike processes: Although regular patterns (bake-baked, step-stepped) appear to be rulelike, English also has a number of irregular forms (take-took, sleep-slept) that conflict with the rule that the past tense is formed by adding -ed to the present tense. Irregular forms are problematic to a rule-based approach because they call into question whether rules alone are sufficient for explaining linguistic phenomena, and whether a secondary mechanism is required for encoding these irregular forms. In 1986, Rumelhart and McClelland proposed a connectionist model in which both regular past tenses and exceptions were encoded within a single type of neural mechanism. The connectionist approach to cognitive neuroscience explains cognitive processes as arising fro

Motor control and nonword repetition in specific working memory impairment and SLI

PURPOSE:: Debate around the underlying cognitive factors leading to poor performance in the repetition of nonwords by children with developmental impairments in language has centered around phonological short-term memory, lexical knowledge, and other factors. This study examines the impact of motor control demands on nonword repetition in groups of school children with specific impairments in language, working memory, or both. METHOD:: Children repeated two lists of nonwords matched for motoric complexity either without constraint or with a gummi bear bite block held between their teeth. The bite block required motoric compensation to reorganize the motor plan for speech production. RESULTS:: Overall, the effect of the biomechanical constraint was very small for all groups. When analyses focused only on the most complex nonwords, children with language impairment were found to be significantly more impaired in the motorically constrained nonword repetition task than the typically developing group. In contrast, working memory difficulties were not differentially linked to motor condition. CONCLUSIONS:: These findings add to the growing evidence that there is a motoric component to developmental language disorders. The results also suggest that the role of speech motor skill in nonword repetition is relatively modest. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins

Sign language ability in young deaf signers predicts comprehension of written sentences in English.

We investigated the robust correlation between American Sign Language (ASL) and English reading ability in 51 young deaf signers ages 7;3 to 19;0. Signers were divided into \u27skilled\u27 and \u27less-skilled\u27 signer groups based on their performance on three measures of ASL. We next assessed reading comprehension of four English sentence structures (actives, passives, pronouns, reflexive pronouns) using a sentence-to-picture-matching task. Of interest was the extent to which ASL proficiency provided a foundation for lexical and syntactic processes of English. Skilled signers outperformed less-skilled signers overall. Error analyses further indicated greater single-word recognition difficulties in less-skilled signers marked by a higher rate of errors reflecting an inability to identify the actors and actions described in the sentence. Our findings provide evidence that increased ASL ability supports English sentence comprehension both at the levels of individual words and syntax. This is consistent with the theory that first language learning promotes second language through transference of linguistic elements irrespective of the transparency of mapping of grammatical structures between the two languages

Reading skill related to left ventral occipitotemporal cortex during a phonological awareness task in 5–6-year old children

The left ventral occipitotemporal cortex (vOT) is important in visual word recognition. Studies have shown that the left vOT is generally observed to be involved in spoken language processing in skilled readers, suggesting automatic access to corresponding orthographic information. However, little is known about where and how the left vOT is involved in the spoken language processing of young children with emerging reading ability. In order to answer this question, we examined the relation of reading ability in 5–6-year-old kindergarteners to the activation of vOT during an auditory phonological awareness task. Two experimental conditions: onset word pairs that shared the first phoneme and rhyme word pairs that shared the final biphone/triphone, were compared to allow a measurement of vOT\u27s activation to small (i.e., onsets) and large grain sizes (i.e., rhymes). We found that higher reading ability was associated with better accuracy of the onset, but not the rhyme, condition. In addition, higher reading ability was only associated with greater sensitivity in the posterior left vOT for the contrast of the onset versus rhyme condition. These results suggest that acquisition of reading results in greater specialization of the posterior vOT to smaller rather than larger grain sizes in young children

Mathematical Abilities in Children with Developmental Language Disorder

Purpose. The present paper provides a scoping review of the literature on mathematical abilities in developmental language disorder (DLD). Children with DLD typically struggle with learning in school, however the mechanism by which DLD impacts academic success is unclear. Mathematics involves demands in the multiple domains, and therefore holds potential for examining the relationship between language and academic performance on tasks mediated by verbal and non-verbal demands. Methods. A scoping review was performed via computerized database searching to examine literature on mathematics and DLD. The 21 papers meeting inclusion criteria compared children with typical development or DLD on various tasks measuring numerical cognition. Results. Children with DLD consistently performed below peers with typical development on number transcoding, counting, arithmetic, and story problem tasks. However, performance was similar to peers with typical development on most number line, magnitude comparison, and conceptual mathematics tasks. Conclusions. The findings suggest a relationship between DLD and mathematics was characterized by more detrimental performance on tasks with higher verbal demands. Results are discussed with respect to typical academic curricula and demonstrate a need for early identification and intervention in DLD to optimize academic outcomes

No statistical learning advantage in children over adults: Evidence from behaviour and neural entrainment.

Explicit recognition measures of statistical learning (SL) suggest that children and adults have similar linguistic SL abilities. However, explicit tasks recruit additional cognitive processes that are not directly relevant for SL and may thus underestimate children\u27s true SL capacities. In contrast, implicit tasks and neural measures of SL should be less influenced by explicit, higher-level cognitive abilities and thus may be better suited to capturing developmental differences in SL. Here, we assessed SL to six minutes of an artificial language in English-speaking children (n = 56, 24 females, M = 9.98 years) and adults (n = 44; 31 females, M = 22.97 years), using explicit and implicit behavioural measures and an EEG measure of neural entrainment. With few exceptions, children and adults showed largely similar performance on the behavioural explicit and implicit tasks, replicating prior work. Children and adults also demonstrated robust neural entrainment to both words and syllables, with a similar time course of word-level entrainment, reflecting learning of the hidden word structure. These results demonstrate that children and adults have similar linguistic SL abilities, even when learning is assessed through implicit performance-based and neural measures