Posts Tagged ‘language’
Posted by Callier Library on November 7, 2009
Background: There is accumulating evidence that adolescents with specific language impairment (SLI) have impairments in domains beyond formal language that may affect academic and social outcomes. The findings of previous studies as well as parent reports of behavioural concerns suggest that they lag behind peers in functions such as self-regulation of verbal behaviour and strategic language use suggesting that executive function may be a potential domain worthy of study in adolescents with SLI. The evaluation of executive functions in daily living could provide critical information for intervention for adolescents with SLI, and also inform studies of the relationship between language and executive functioning in a developing system.
Aims: To compare ratings of executive function in adolescents with specific language impairment to those of their parents and typically developing peers.
Methods & Procedures: This study examined parent and self-ratings of executive function in adolescents with SLI and typically developing peers. Twenty-one adolescents with SLI and 21 age- and gender-matched peers (age range = 11-18 years) rated their executive functions in daily living using the Behavior Rating Inventory of Executive Function — Self-Report Form (BRIEF-SR), and their parents provided companion ratings.
Outcomes & Results: Adolescents in both groups rated themselves more positively than did their parents, and the presence of language impairment was associated with more negative ratings by both parents and adolescents. Fifty-seven per cent of the parents of adolescents with SLI rated their child’s executive function abilities as being in the clinically impaired range, compared with 10% in the typically developing group.
Conclusions & Implications: The results of this study suggest that many adolescents with SLI have perceived impairments in executive functions that affect their performance in daily living. What remains to be determined is whether language and executive function impairments are co-morbid conditions or causally linked. Few assessment tools address the unique characteristics of adolescent clinical populations, including those with SLI. These findings suggest that self- and parent ratings of executive function may offer useful information for treatment planning. A greater understanding of the relation of executive functions to language has important implications for the timing and content of therapeutic intervention.
from the International Journal of Language and Communication Disorders
Posted in Research | Tagged: adolescents, executive functions, language, parents, specific language impairment (SLI) | Leave a Comment »
Posted by Callier Library on November 3, 2009
In a prior study (Newman & Bernstein Ratner, 2007), we examined the effects of word frequency and phonological neighborhood characteristics on confrontation naming latency, accuracy and fluency in adults who stutter and typically-fluent speakers. A small difference in accuracy favoring fluent adults was noted, but no other patterns differentiated fluent speaker responses from those obtained from the adults who stutter. Because lexical organization or retrieval differences might be more easily observed in less mature language users, we replicated the experiment using 15 children who stutter (ages 4;10 16;2) and age-and gender-matched peers. Results replicated the earlier study: the two groups of participants showed strikingly similar patterns of responses based on word frequency and neighborhood characteristics. There were also no differences in naming accuracy overall between the two groups. Given our results and those of other researchers who have explored the impact of neighborhood variables on lexical retrieval in people who stutter, we suggest that differences between language production in PWS and fluent speakers are not likely to involve atypical phonological organization of lexical neighborhoods.
from Journal of Fluency Disorders
Posted in Research | Tagged: children, language, Lexical retrieval, phonology, stuttering | Leave a Comment »
Posted by Callier Library on October 28, 2009
Including children as research participants is an important new direction in early childhood research. However, it is rare for such studies to include the voices of children with significant communication impairment. This article suggests that drawing may be an appropriate non-verbal method for ‘listening’ to these children’s ideas and recording their perspectives. Three areas of inquiry are reviewed: (1) the use of drawings as a method of listening respectfully to children; (2) approaches to the analysis of children’s drawings; and (3) the analysis of drawings completed by children with communication impairment. We identify six aspects of children’s drawings — facial expressions, accentuation of body features (e.g. mouth and ears), portrayal of talking/listening, colours used, conversational partners, and sense of self — that are potentially pertinent for children with communication impairment.
from the Journal of Early Childhood Research
Posted in Research | Tagged: children, communication, drawing, language, speech | Leave a Comment »
Posted by Callier Library on October 21, 2009
Objectives: to examine the association of language (English vs Spanish), and commonly used measures of memory and word fluency among older adults.
Design: cross-sectional.
Setting: community-based settings in New York City, including senior centres and residential complexes.
Subjects: four hundred and twenty independently living adults aged 60 or older (mean 73.8 years).
Methods: participants completed the Mini-Mental State Exam (MMSE), animal naming test (ANT) and Wechsler Memory Scale III (WMS) Story A immediate and delayed subtests. Scores were examined by strata of language, age or education and for different thresholds of the MMSE. We tested the association of language and cognitive test performance using multivariable linear regression.
Results: twenty-one per cent of subjects were interviewed in Spanish and 16.2% reported poor-fair English proficiency. The mean WMS scores were not statistically different between English and Spanish groups (immediate recall, 9.9 vs 9.5, P = 0.44; delayed recall, 8.0 vs 7.6, P = 0.36, respectively), whereas ANT scores did differ (16.6 vs 14.3, P < 0.0001). These associations were consistent across MMSE thresholds. The association of language and ANT score was not significant after accounting for education.
Conclusions: we found little difference in performance on the Story A subtests from the WMS suggesting that this test may be used for both English- and Spanish-speaking populations. Results suggest that variations in ANT performance may be accounted for by adjusting for the level of education. These results have important implications for the generalisability of test scores among diverse older populations.
from Age and Ageing
Posted in Research | Tagged: cognition, elderly, language, Spanish | Leave a Comment »
Posted by Callier Library on October 15, 2009
Modern lesion and imaging work in humans has been clarifying which brain regions are involved in the processing of speech and language. Concurrently, some of this work has aimed to bridge the gap to the seemingly incompatible evidence for multiple brain-processing pathways that first accumulated in nonhuman primates. For instance, the idea of a posterior temporal-parietal “Wernicke’s” territory, which is thought to be instrumental for speech comprehension, conflicts with this region of the brain belonging to a spatial “where” pathway. At the same time a posterior speech-comprehension region ignores the anterior temporal lobe and its “what” pathway for evaluating the complex features of sensory input. Recent language models confirm that the posterior or dorsal stream has an important role in human communication, by a reconceptualization of the “where” into a “how-to” pathway with a connection to the motor system for speech comprehension. Others have tried to directly implicate the “what” pathway for speech comprehension, relying on the growing evidence in humans for anterior-temporal involvement in speech and voice processing. Coming full circle, we find that the recent imaging of vocalization and voice preferring regions in nonhuman primates allows us to make direct links to the human imaging data involving the anterior-temporal regions. The authors describe how comparison of the structure and function of the vocal communication system of humans and other animals is clarifying evolutionary relationships and the extent to which different species can model human brain function.
from the Neuroscientist
Posted in Research | Tagged: animal, communication, Evolution, language, primate | Leave a Comment »
Posted by Callier Library on October 13, 2009
Abstract
Children with congenital left hemisphere damage due to perinatal stroke are capable of acquiring relatively normal language functions despite experiencing a cortical insult that in adults often leads to devastating lifetime disabilities. Although this observed phenomenon is accepted, its neurobiological mechanisms are not well characterized. In this paper we examined the functional neuroanatomy of lexical processing in 13 children/adolescents with perinatal left hemispheric damage. In contrast to many previous perinatal infarct fMRI studies, we used an event-related design, which allowed us to isolate trial-related activity and examine correct and error trials separately. Using both group and single subject analysis techniques we attempt to address several methodological factors that may contribute to some discrepancies in the perinatal lesion literature. These methodological factors include making direct statistical comparisons, using common stereotactic space, using both single subject and group analyses, and accounting for performance differences. Our group analysis, investigating correct trial-related activity (separately from error trials), showed very few statistical differences in the non-involved right hemisphere between patients and performance matched controls. The single subject analysis revealed atypical regional activation patterns in several patients; however, the location of these regions identified in individual patients often varied across subjects. These results are consistent with the idea that alternative functional organization of trial-related activity after left hemisphere lesions is in large part unique to the individual. In addition, reported differences between results obtained with event-related designs and blocked designs may suggest diverging organizing principles for sustained and trial-related activity after early childhood brain injuries.
from Brain and Language
Posted in Research | Tagged: stroke, brain, children, fMRI, language, development, congenital, imaging, Lesion, Perinatal | Leave a Comment »
Posted by Callier Library on October 12, 2009
Children with congenital left hemisphere damage due to perinatal stroke are capable of acquiring relatively normal language functions despite experiencing a cortical insult that in adults often leads to devastating lifetime disabilities. Although this observed phenomenon is accepted, its neurobiological mechanisms are not well characterized. In this paper we examined the functional neuroanatomy of lexical processing in 13 children/adolescents with perinatal left hemispheric damage. In contrast to many previous perinatal infarct fMRI studies, we used an event-related design, which allowed us to isolate trial-related activity and examine correct and error trials separately. Using both group and single subject analysis techniques we attempt to address several methodological factors that may contribute to some discrepancies in the perinatal lesion literature. These methodological factors include making direct statistical comparisons, using common stereotactic space, using both single subject and group analyses, and accounting for performance differences. Our group analysis, investigating correct trial-related activity (separately from error trials), showed very few statistical differences in the non-involved right hemisphere between patients and performance matched controls. The single subject analysis revealed atypical regional activation patterns in several patients; however, the location of these regions identified in individual patients often varied across subjects. These results are consistent with the idea that alternative functional organization of trial-related activity after left hemisphere lesions is in large part unique to the individual. In addition, reported differences between results obtained with event-related designs and blocked designs may suggest diverging organizing principles for sustained and trial-related activity after early childhood brain injuries.
from Brain and Language
Posted in Research | Tagged: stroke, brain, children, fMRI, language, development, congenital, imaging, Lesion, Perinatal | Leave a Comment »
Posted by Callier Library on October 12, 2009
Young children with typical fluency demonstrate a range of disfluencies, or speech disruptions. One type of disruption, revision, appears to increase in frequency as syntactic skills develop. To date, this phenomenon has not been studied in children who stutter (CWS). Rispoli and colleagues (2008) suggest a schema for categorizing speech disruptions in terms of revisions and stalls. The purpose of this exploratory study was to use this schema to evaluate whether CWS show a pattern over time in their production of stuttering, revisions, and stalls. Nine CWS, ages 2;1 to 4;11, participated in the study, producing language samples each month for 10 months. MLU and vocd analyses were performed for samples across three time periods. Active declarative sentences within these samples were examined for the presence of disruptions. Results indicated that the proportion of sentences containing revisions increased over time, but proportions for stalls and stuttering did not. Visual inspection revealed that more stuttering and stalls occurred on longer utterances than on shorter utterances. Upon examination of individual children’s language, it appears two-thirds of the children showed a pattern in which, as MLU increased, revisions increased as well. Findings are similar to studies of children with typical fluency, suggesting that, despite the fact that CWS display more (and different) disfluencies relative to typically fluent peers, revisions appear to increase over time and correspond to increases in MLU, just as is the case with peers.
from Journal of Fluency Disorders
Posted in Research | Tagged: children, disruptions, language, Longitudinal, stuttering | Leave a Comment »
Posted by Callier Library on October 9, 2009
The speech of patients with progressive non-fluent aphasia (PNFA) has often been described clinically, but these descriptions lack support from quantitative data. The clinical classification of the progressive aphasic syndromes is also debated. This study selected 15 patients with progressive aphasia on broad criteria, excluding only those with clear semantic dementia. It aimed to provide a detailed quantitative description of their conversational speech, along with cognitive testing and visual rating of structural brain imaging, and to examine which, if any features were consistently present throughout the group; as well as looking for sub-syndromic associations between these features. A consistent increase in grammatical and speech sound errors and a simplification of spoken syntax relative to age-matched controls were observed, though telegraphic speech was rare; slow speech was common but not universal. Almost all patients showed impairments in picture naming, syntactic comprehension and executive function. The degree to which speech was affected was independent of the severity of the other cognitive deficits. A partial dissociation was also observed between slow speech with simplified grammar on the one hand, and grammatical and speech sound errors on the other. Overlap between these sets of impairments was however, the rule rather than the exception, producing continuous variation within a single consistent syndrome. The distribution of atrophy was remarkably variable, with frontal, temporal and medial temporal areas affected, either symmetrically or asymmetrically. The study suggests that PNFA is a coherent, well-defined syndrome and that varieties such as logopaenic progressive aphasia and progressive apraxia of speech may be seen as points in a space of continuous variation within progressive non-fluent aphasia.
from Brain
Posted in Research | Tagged: neuropsychology, frontotemporal dementia, language, progressive aphasia, cortical atrophy | Leave a Comment »
Posted by Callier Library on October 7, 2009
Five nonfluent aphasia patients participated in a picture-naming treatment that used an intention manipulation (opening a box and pressing a button on a device in the box with the left hand) to initiate naming trials and was designed to re-lateralize word production mechanisms from the left to the right frontal lobe. To test the underlying assumption regarding re-lateralization, patients participated in fMRI of category-member generation before and after treatment. Generally, the four patients who improved during treatment showed reduced frontal activity from pre- to post-treatment fMRI with increasing concentration of activity in the right posterior frontal lobe (motor/premotor cortex, pars opercularis), demonstrating a significant shift in lateraliity toward the right lateral frontal lobe, as predicted. Three of these four patients showed no left frontal activity by completion of treatment, indicating that right posterior lateral frontal activity supported category-member generation. Patients who improved in treatment showed no difference in lateralization of lateral frontal activity from normal controls pre-treatment, but post-treatment, their lateral frontal activity during category-member generation was significantly more right lateralized than that of controls. Patterns of activity pre- and post-treatment suggested increasing efficiency of cortical processing as a result of treatment in the four patients who improved. The one patient who did not improve during treatment showed a leftward shift in lateral frontal lateralization that was significantly different from the four patients who did improve. Neither medial frontal nor posterior perisylvian re-lateralization from immediately pre- to immediately post-treatment images was a necessary condition for significant treatment gains or shift in lateral frontal lateralization. Of the three patients who improved and in whom posterior perisylvian activity could be measured at post-treatment fMRI, all maintained equal or greater amounts of left-hemisphere perisylvian activity as compared to right. This finding is consistent with reviews suggesting both hemispheres are involved in recovery of language in aphasia patients.
from the Journal of Voice
Posted in Research | Tagged: aphasia, attention, fMRI, intention, language, neuroimaging, neuroplasticity, rehabilitation | Leave a Comment »
Posted by Callier Library on September 30, 2009
The relationship between nonword repetition ability and vocabulary size and vocabulary learning has been a topic of intense research interest and investigation over the last two decades, following the demonstration that nonword repetition accuracy is predictive of vocabulary size (Gathercole & Baddeley, 1989). However, the nature of this relationship is not well understood. One prominent account posits that phonological short-term memory (PSTM) is a causal determinant both of nonword repetition ability and of phonological vocabulary learning, with the observed correlation between the two reflecting the effect of this underlying third variable (e.g., Baddeley, Gathercole, & Papagno, 1998). An alternative account proposes the opposite causality: that it is phonological vocabulary size that causally determines nonword repetition ability (e.g., Snowling, Chiat, & Hulme, 1991). We present a theory of phonological vocabulary learning, instantiated as a computational model. The model offers a precise account of the construct of PSTM, of performance in the nonword repetition task, of novel word form learning, and of the relationship between all of these. We show through simulation not only that PSTM causally affects both nonword repetition accuracy and phonological vocabulary size, but also that phonological vocabulary size causally affects nonword repetition ability. The plausibility of the model is supported by the fact that its nonword repetition accuracy displays effects of phonotactic probability and of nonword length, which have been taken as evidence for causal effects on nonword repetition accuracy of phonological vocabulary knowledge and PSTM, respectively. Thus the model makes explicit how the causal links posited by the two theoretical perspectives are both valid, in the process reconciling the two perspectives, and indicating that an opposition between them is unnecessary.
from the Journal of Memory and Language
Posted in Research | Tagged: Computational modeling, language, nonword repetition, Phonological memory, short-term memory, vocabulary learning, word learning | Leave a Comment »
Posted by Callier Library on September 30, 2009
This study investigated metaphor comprehension in the broader context of task-difference effects and manipulation of processing difficulty. We predicted that right hemisphere recruitment would show greater specificity to processing difficulty rather than metaphor comprehension. Previous metaphor processing studies have established that the left inferior frontal gyrus strongly correlates with metaphor comprehension but there has been controversy about whether right hemisphere (RH) involvement is specific for metaphor comprehension. Functional MRI data were recorded from healthy subjects who read novel metaphors, conventional metaphors, definition-like sentences, or literal sentences. We investigated metaphor processing in contexts where semantic judgment or imagery modulates linguistic judgment. Our findings support the position that the type of task rather than figurative language processing per se modulates the left inferior gyrus (LIFG). RH involvement was more influenced by processing difficulty and less by the novelty or figurativity of linguistic expressions. Our results suggest that figurative language processing depends upon the effects of task-type and processing difficulty on imaging results.
from Brain and Language
Posted in Research | Tagged: fMRI, language, left inferior frontal gyrus, Processing difficulty, semantic | Leave a Comment »
Posted by Callier Library on September 30, 2009
Everyday conversation is both an auditory and a visual phenomenon. While visual speech information enhances comprehension for the listener, evidence suggests that the ability to benefit from this information improves with development. A number of brain regions have been implicated in audiovisual speech comprehension, but the extent to which the neurobiological substrate in the child compares to the adult is unknown. In particular, developmental differences in the network for audiovisual speech comprehension could manifest through the incorporation of additional brain regions, or through different patterns of effective connectivity. In the present study we used functional magnetic resonance imaging and structural equation modeling (SEM) to characterize the developmental changes in network interactions for audiovisual speech comprehension. The brain response was recorded while children 8- to 11-years-old and adults passively listened to stories under audiovisual (AV) and auditory-only (A) conditions. Results showed that in children and adults, AV comprehension activated the same fronto-temporo-parietal network of regions known for their contribution to speech production and perception. However, the SEM network analysis revealed age-related differences in the functional interactions among these regions. In particular, the influence of the posterior inferior frontal gyrus/ventral premotor cortex on supramarginal gyrus differed across age groups during AV, but not A speech. This functional pathway might be important for relating motor and sensory information used by the listener to identify speech sounds. Further, its development might reflect changes in the mechanisms that relate visual speech information to articulatory speech representations through experience producing and perceiving speech.
from Brain and Language
Posted in Research | Tagged: fMRI, language, development, supramarginal gyrus, Pars opercularis, inferior frontal gyrus, audiovisual speech, Posterior superior temporal sulcus, Structural equation models, Ventral premotor | Leave a Comment »
Posted by Callier Library on September 29, 2009
Results: Parent-reported prevalence: 25.2% had concerns about how their child talked and made speech sounds (11.8% “concerned”; 13.4% “a little concerned”), and 9.5% had concerns about how their child understood language (4.4% “concerned”; 5.1% “a little concerned”). Parents who reported concerns identified “speech not clear to others” as the most frequent area of difficulty (12.0%). Teacher-reported prevalence: 22.3% of children were considered to be less competent than others in their expressive language ability (6.7% “much less competent”; 15.6% “less competent”); 16.9% were considered to be less competent than others in their receptive language ability (4.0% “much less competent”; 12.9% “less competent”). The match between parent and teacher identification was higher for expressive speech and language concern than for receptive language. Direct assessment: 13.0% of children were 1–2 SDs below the mean on the Adapted Peabody Picture Vocabulary Test–III (S. Rothman, 2003), and a further 1.7% were > 2 SDs below the mean. Parent and teacher reports were significantly correlated with scores obtained via direct assessment. Period prevalence: Parents and teachers reported that 14.5% of children had accessed speech-language pathologist (SLP) services. 2.2% indicated that they needed but could not access an SLP.
Conclusion: Multiple indicators of speech and language impairment in diverse contexts confirmed the high prevalence of this condition in early childhood and a concomitant need for SLP services.
from the Journal of Speech, Language, and Hearing Research
Posted in Research | Tagged: children, communication, epidemiology, language, prevalence, speech | Leave a Comment »
Posted by Callier Library on September 29, 2009
Speech comprehension involves processing at different levels of analysis, such as acoustic, phonetic, and lexical. We investigated neural responses to manipulating the difficulty of processing at two of these levels. Twelve subjects underwent positron emission tomographic scanning while making decisions based upon the semantic relatedness between heard nouns. We manipulated perceptual difficulty by presenting either clear or acoustically degraded speech, and semantic difficulty by varying the degree of semantic relatedness between words. Increasing perceptual difficulty was associated with greater activation of the left superior temporal gyrus, an auditory-perceptual region involved in speech processing. Increasing semantic difficulty was associated with reduced activity in both superior temporal gyri and increased activity within the left angular gyrus, a heteromodal region involved in accessing word meaning. Comparing across all the conditions, we also observed increased activation within the left inferior prefrontal cortex as the complexity of language processing increased. These results demonstrate a flexible system for language processing, where activity within distinct parts of the network is modulated as processing demands change. Hum Brain Mapp, 2009. © 2009 Wiley-Liss, Inc.
from Human Brain Mapping
Posted in Research | Tagged: language, perception, PET, prefrontal, semantic | Leave a Comment »