Temporal Dynamics of Adaptation to Natural Sounds in the Human Auditory Cortex
from Cerebral Cortex
We aimed at testing the cortical representation of complex natural sounds within auditory cortex by conducting 2 human magnetoencephalography experiments. To this end, we employed an adaptation paradigm and presented subjects with pairs of complex stimuli, namely, animal vocalizations and spectrally matched noise. In Experiment 1, we presented stimulus pairs of same or different animal vocalizations and same or different noise. Our results suggest a 2-step process of adaptation effects: first, we observed a general item-unspecific reduction of the N1m peak amplitude at 100 ms, followed by an item-specific amplitude reduction of the P2m component at 200 ms after stimulus onset for both animal vocalizations and noise. Multiple dipole source modeling revealed the right lateral Heschl’s gyrus and the bilateral superior temporal gyrus as sites of adaptation. In Experiment 2, we tested for cross-adaptation between animal vocalizations and spectrally matched noise sounds, by presenting pairs of an animal vocalization and its corresponding or a different noise sound. We observed cross-adaptation effects for the P2m component within bilateral superior temporal gyrus. Thus, our results suggest selectivity of the evoked magnetic field at 200 ms after stimulus onset in nonprimary auditory cortex for the spectral fine structure of complex sounds rather than their temporal dynamics.
What constrains sentence production in agrammatism?
from Brain and Language
No abstract available.
When the grammatical principle of agreement is itself restricted in agrammatism
from Brain and Language
No abstract available.
Who needs Broca’s area? Comparisons from lesion and fMRI methods
from Brain and Language
No abstract available.
Why RHD individuals have more difficulties with direct requests than indirect requests? A theory of mind hypothesis
from Brain and Language
No abstract available.
Verb production in sentences by patients with nonfluent progressive aphasia
from Brain and Language
No abstract available.
Verb argument structure encoding during sentence production in agrammatic aphasic speakers: An eye-tracking study
from Brain and Language
No abstract available.
The temporal analysis of semantic perseverations in blocked-cyclic naming
from Brain and Language
No abstract available.
The role of argument structure in the processing of nouns and verbs: An f-MRI study
from Brain and Language
No abstract available.
The representation of letter position: Evidence from dysgraphia
from Brain and Language
No abstract available.
The processing of compounds in bilingual aphasia
from Brain and Language
Discussion
Our main objective was to investigate whether the individual constituents of a compound are processed differentially across the two languages of bilingual aphasic patients. Both patients tested showed a similar behavioural pattern: a significantly reduced number of errors for the head (the first constituent) as compared to the second constituent in French and an equivalent number of errors for both constituents in English, pointing to the cumulative effects of headedness and first-position-in-the-string in French, and to the mutual cancelling out of these effects in English. In conclusion, our results from the performances of two bilingual aphasic participants, together with those of Jarema et al. (1999) on unimpaired individuals, reveal that headedness and position interact in the processing of compounds and that aphasic patients are sensitive to compound-internal structure. Furthermore, these findings underscore the importance of taking into account cross-linguistic variation in our understanding of the manner in which compound words are processed in both normal and pathological populations.
The neural systems underlying lexical competition in speech production: Evidence from Aphasia
from Brain and Language
Conclusion
The findings of this study address several issues relating to the functional architecture of the language system and the neural systems underlying this architecture. With respect to the functional architecture of the language system, they indicate that the statistical properties of words, as measured by lexical density, have consequences for speech production as well as word recognition and suggest that a common lexical system drives both production and processing streams. The basis for the density effect in production is likely due to the increased activation required to access a word with many phonological competitors and the cascading effects of those processes on articulatory implementation. With respect to the neural systems underlying this architecture, they suggest that the SMG is involved in phonological processing (Paulesu, Frith, & Frackowiak, 1993) and that there are greater processing requirements for words from phonologically similar neighborhoods. Such a deficit provides a potential explanation for conduction aphasics’ production of phonemic paraphasias. Finally, the results suggest that although damage to the IFG results in speech output deficits, lexical access processes remain intact.
The neural correlates of abstract versus concrete words: Evidence from an rTMS study
from Brain and Language
This experiment suggests that right hemisphere structures located in the ITG are involved in processing abstract terms, but are not critical for the processing of concrete words. Further studies need to be performed in order (i) to assess the role of additional sites, such as the left superior and inferior frontal gyri, as suggested by the neuroimaging literature, and (ii) to confirm these preliminary results.
The nature of the processing distinction between regular and irregular verbs: Evidence from an English–German bilingual aphasic speaker
from Brain and Language
Discussion
The results in English and German showed an overall similar pattern: responses were less accurate for those verbs that required memory-based, retrieval processes. That is, performance was worse with irregular than for regular verbs. Furthermore, in German a striking difference was observed between stem-change and no-stem-change irregulars. This difference can be understood if we assume that irregulars differ in the extent to which they require memory-based, retrieval steps for their accurate production. These results support a distinction between memory-based, retrieval and rule-based, assembly processes that will yield different patterns of performance on regulars and irregular verbs within and across languages depending on the degree to which the verbs depend on these two process types.
The manifestation of agrammatic comprehension in a case of crossed aphasia
from Brain and Language
Like comprehension of declarative sentences, comprehension of wh-questions in agrammatism reveals aspects of linguistic architecture. We present an agrammatic speaker with crossed aphasia (CA). In CA the lesion is located in the right hemisphere in a right-handed individual. Unlike the classical and typical syndromes CA is a rare and controversial syndrome and theoretically interesting. Studies of CA have shown diverse and, in some cases, unusual neurobehavioral symptoms. It has been suggested that CA can be a mirror image of classical syndromes or anomalous (Alexander, Fischette, & Fischer, 1989). Our speaker exhibits a classic pattern between canonical (agent-patient) and non-canonical (patient-agent) declarative sentences and, contrary to other reported cases, the same pattern between canonical and non-canonical wh-questions.
The importance of verb form-regularity in agrammatism
from Brain and Language
Conclusion
The relatively greater errors for ser than for estar for the agrammatic participants, coupled with the greater likelihood of substituting estar for ser, rather than vice versa, argues for greater weight given to regularity than to frequency in determining agrammatic usage, consistent with de Diego Balaguer et al. (2004) and contra Ullman et al. (1997).
The electrophysiological correlates of Noun–Noun compounds
from Brain and Language
The “head” of a compound is the component determining the lexical category, the gender and the semantic traits of the whole compound. Despite its importance, the precise role of the “head” dimension has been almost missing from aphasiological investigations (Semenza & Mondini, 2006). The present study aims to better understand the processing of head- and non-head components in nominal compounds using ERPs (event-related potentials).
The decline of narrative discourse in Alzheimer’s disease
from Brain and Language
Objective
Patients with Alzheimer’s disease (AD) appear to have a disorder of discourse. However, the speech sample elicited by a picture description task is typically too brief to establish anything beyond the presence of a deficit. Likewise, the basis for a discourse deficit can be difficult to identify in a spontaneous speech sample where the intended target is not well specified. To characterize the nature of the deficits in discourse and identify the neuropsychological underpinnings of such deficits, we analyzed deviance in the accuracy and cohesiveness of a semi-structured speech sample in AD and healthy seniors elicited by a wordless children’s picture story.
The contribution of cognitive mechanisms to verb production in Dutch speaking Parkinson’s disease patients
from Brain and Language
There is a growing interest in the origin of language problems in Parkinson’s disease (PD). In PD sentence comprehension is influenced by cognitive functions, such as working memory, inhibition, and switching (e.g. [Caplan and Waters, 1999], [Grossman et al., 2002] and [Hochstadt et al., 2006]).
As for the production of verbs in sentences, the performance of Dutch and English Broca patients is influenced by linguistic complexity: transitivity (intransitive > transitive), position of the verb (base > derived), finiteness (infinitive > finite), reference time (present > past), and regularity of past tense (irregular > regular) ([Bastiaanse, in press], [Kim and Thompson, 2000], [Thompson, 2003] and [Ullman, 2001]).
The present study investigates the relation between verb production in sentences and linguistic and cognitive functioning in Dutch speaking PD-patients.
Syntactic and thematic constraint effects on BOLD signal correlates of comprehension of relative clausesstar, open
from Brain and Language
Increases in neurovascular responses associated with object- compared to subject-extracted relative clauses have been interpreted as providing evidence regarding the localization of the neural structures that support the memory and computational demands associated with assigning the object-extracted structure. However, recent studies have shown an interaction of syntactic structure and the order of animate and inanimate nouns on BOLD signal ([Caplan and Chen, 2006], [Caplan, in press] and [Chen et al., 2006]). Studies that use sentences containing only animate nouns that are not constrained to play particular thematic roles around the verbs in the sentences have been used to avoid these semantic influences ([Fiebach et al., 2001], [Fiebach et al., 2005] and [Just et al., 1996]) but eye tracking data shows that there is a late review of structure in pragmatically unconstrained object-extracted relative clauses (Traxler, Morris, & Seely, 2002). This review, rather than initial parsing, may account for the BOLD effects of the object/subject extraction contrast in these studies. The present study explores the BOLD signal correlates of assigning the structure and meaning of sentences with subject- and object-extracted relative clauses and unconstrained and constrained thematic roles.
Disorders of cognitive and affective development in cerebellar malformations
from Brain
Acquired cerebellar lesions in adults and children can lead to the development of a complex behavioural pattern termed ‘Cerebellar Cognitive Affective Syndrome’ (Schmahmann and Sherman, Brain, 1998; 121: 561–79), which is characterized by reduced cognitive efficiency associated with specific neuropsychological deficits (executive and visuospatial disorders), expressive language disorders (mild agrammatism and anomia) and affective disorders with blunting of affect. It is not known whether a symptomatological picture such as this can also be found in congenital cerebellar malformations. We studied the behavioural developmental profile of 27 patients including children and adults with congenital malformations confined to the cerebellum, the largest studied sample to date. Extensive clinical and neuropsychological investigations highlight the presence of a wide range of disorders supporting the important role played by the cerebellum in the acquisition of higher-order cognitive and affective skills. The type and extent of cerebral reorganization processes in the presence of malformative lesions are difficult to predict and may possibly account for the variability of clinical phenotypes. It is, therefore, more difficult to identify a syndromic picture defined as exactly as is the case with acquired lesions. However, the pattern of deficits that we document is in remarkable agreement with the general profile of the Cerebellar Cognitive Affective Syndrome. Malformations affecting the cerebellar vermis induce affective and social disorders and evolve towards more unfavourable pictures often associated with an autistic symptomatology. Malformations of cerebellar hemispheres are more frequently associated with selective neuropsychological deficits involving mainly executive functions and visuospatial and linguistic abilities. Motor deficits are generally less severe, and tend to improve slowly and progressively, in some cases reaching almost complete functionality. Finally, the overall favourable evolution with an onset of skills in advanced age in a consistent subset of subjects suggests that individual follow-ups should be performed in order to monitor the quality and stability of impairments and acquired abilities over time.
Thiomersal in vaccines is not associated with neurodevelopmental disorders
from the National electronic Library for Medicines (NeLM)
A major US study has found no significant association between childhood exposure to thiomersal in vaccines and neurodevelopment between the ages of seven to ten.
Nigeria: Group Highlights Plight of Children With Autism
from All Africa.com
The majority of children with behaviour, attention, language, communication and learning disabilities such as autism in our country are not being identified early enough, an expert has said.
Clarifying Differences in Definitions Between ASHA Policy Documents and the Authors in “The Critical Shortage of Speech-Language Pathologists in the Public School Setting: Features of the Work Environment That Affect Recruitment and Retention
from Language, Speech, and Hearing Services in Schools
Purpose: The January 2007 issue of Language, Speech, and Hearing Services in Schools includes an article by D. Edgar and L. Rosa-Lugo entitled “The Critical Shortage of Speech-Language Pathologists in the Public School Setting: Features of the Work Environment That Affect Recruitment and Retention.” In their article, the authors cite the American Speech- Language-Hearing Association (ASHA) policy document “A Workload Analysis Approach for Establishing Speech-Language Caseload Standards in Schools: Guidelines” (ASHA, 2002) and include the term workload in their survey instrument and study results. However, their definition of workload differs from the definition in ASHA policy documents. In addition, they provide some information from the ASHA Technical Report on workload (ASHA, 2002) that may be misconstrued out of context. The purpose of this letter is to reduce the possibility of any misunderstanding on the part of readers by highlighting the differences in definitions between the authors’ work and ASHA policy documents and by providing context for information from the policy document. Conclusion: D. Edgar and L. Rosa-Lugo should be commended for conducting research related to the successful recruitment and retention of qualified speech-language pathologists in schools. Hopefully, these comments will contribute to those discussions by clarifying important points. [ABSTRACT FROM AUTHOR]
Comparison of Language Skills of Adjudicated and Nonadjudicated Adolescent Males and Females
from Language, Speech, and Hearing Services in Schools
Purpose: This study attempted to determine whether there were any differences or similarities in the basic cognitive and language skills of 4 groups of adolescents: adjudicated (a judge’s decision to establish responsibility for a delinquent act) and nonadjudicated male and females. Method: The 4 groups of adolescents were 18 adjudicated females, 18 nonadjudicated females, 14 adjudicated males, and 14 nonadjudicated males. They were evaluated using the Kaufman Brief Intelligence Test (K-BIT; A. S. Kaufman & N. L. Kaufman, 1990) as a screener for intelligence and the Clinical Evaluation of Language Fundamentals–3 (CELF-3; E. Semel, E. Wiig, & W. Secord, 1995) as a screener for language skills. Results: No gender differences were found between the groups for either the K-BIT or the CELF-3. All groups scored within normal limits on the K-BIT subtests, but lower on the vocabulary portion of the K-BIT compared to the matrices (nonverbal) portion. There were differences found between adjudicated and nonadjudicated groups on the CELF-3, with the adjudicated groups having lower scores. Implications: As the majority of adjudicated adolescents had not been previously identified as having difficulties with language abilities, this population could benefit from early assessment. Also, children who are at risk for incarceration should be screened for possible language deficits that could contribute to the many difficulties experienced by adolescents. [ABSTRACT FROM AUTHOR]
Complexities of Expressive Word Learning Over Time
from Language, Speech, and Hearing Services in Schools
Purpose: The purpose of this study was to examine semantic and lexical aspects of word learning over time. Method: Thirty-four 8-year-olds participated in vocabulary lessons for 2 weeks. Frequency of exposure and informativeness of semantic context were manipulated. A definition task assessed semantic learning and a naming task assessed lexical learning. Results: Semantic and lexical knowledge accrued over time and were maintained after a 1-month interval. Higher frequency of exposure had an immediate effect on semantic learning and a more gradual effect on lexical learning. Frequency of exposure coupled with informative context promoted semantic learning. Clinical Implications: Speech-language pathologists should be mindful of the richness of the learning context and the redundancy of massed and distributed exposures. Learning at the semantic and lexical levels can dissociate so both should be addressed. [ABSTRACT FROM AUTHOR]
Electroacoustic Evaluation of Frequency-Modulated Receivers Interfaced With Personal Hearing Aids
from Language, Speech, and Hearing Services in Schools
Purpose: The purpose of this study was to compare the electroacoustic outputs of frequency-modulated (FM) systems coupled to hearing aids. Method: Electroacoustic performance of FM systems coupled to hearing aids was determined for 3 FM receivers: body-worn with neck loop, ear-level nonprogrammable, and ear-level programmable. Systems were evaluated using the FM-advantage approach suggested by the American Speech-Language-Hearing Association’s “Guidelines for Fitting and Monitoring FM Systems” (2002). Output differences between the hearing aid and FM system were examined for typical input levels with a complex signal to verify an FM advantage and for high-input levels with a pure-tone signal to confirm similarity in maximum output. Results: Measurements from the FM receivers with neck loops showed significant low-frequency reduction and the most variable performance of the 3 types of systems. Less variable measurements were obtained with the ear-level FM receivers, and programmable FM receivers allowed for the most flexibility in obtaining an FM advantage. Findings of variability may be related to the type of system and the compression characteristics of the devices. Conclusion: Findings of great variability in electroacoustic performance of all systems support the need for electroacoustic evaluation, particularly when observing the effects of various settings on new technology. [ABSTRACT FROM AUTHOR]
Exploration of Lexical-Semantic Factors Affecting Stress Production in Derived Words
from Language, Speech, and Hearing Services in Schools
Purpose: This study examined whether lexical frequency, semantic knowledge, or sentence context affect children’s production of primary stress in derived words with stress-changing suffixes (e.g., -ity ). Method: Thirty children (M<sub>age</sub> = 9;1 [years;months]) produced a limited set of high-frequency (HF) and low-frequency (LF) derived words formed with stress-changing suffixes (e.g., -ity ). Half of the children produced the derived words in a sentence context. The other half produced words in isolation. Semantic knowledge of the derived words was also assessed. Results: Primary stress was produced more accurately in HF words than in LF words. HF words produced in a sentence context were more accurate than all LF words and HF words produced in isolation. Both knowing a word’s meaning and accurately producing stress was more likely for HF words than for LF words. A substantial minority of derived words (36%) was either known semantically or produced correctly, but not both. Conclusion: Accurate morphophonological production may involve semantic and frequency factors, but those factors alone do not explain all of the results. This study isolates several important factors that may be useful when choosing derived word stimuli. [ABSTRACT FROM AUTHOR]
Longitudinal Effects of Phonological Awareness Intervention on Morphological Awareness in Children With Speech Impairment
from Language, Speech, and Hearing Services in Schools
Purpose: This study examined reading performance and morphological awareness development in 2 groups of children with speech impairment who had received differing types of intervention during their preschool years. Method: The children were aged between 7;6 and 9;5 (years; months) at the time of the study. Group 1 (n = 
had received preschool intervention to facilitate phonological awareness and letter knowledge in addition to improving speech production. Group 2 (n = 9) had received preschool intervention that focused solely on improving speech intelligibility. A third group of children with typical development (Group 3, n = 24) also participated in the study. Two reading tests were administered, one that assessed word recognition and another that assessed nonword decoding. Two tests of morphological awareness were also administered, one that tested the spelling of morphologically complex words and another that tested the oral generation of the base form of derived words. Results: Children with a history of speech impairment who had received phonological awareness intervention (Group 1) performed significantly better on nonword decoding and on the spelling of morphologically complex words than did children with a history of speech impairment whose intervention focused on speech only (Group 2). The typically developing children (Group 3) were not significantly different from Group 1 on the spelling of morphologically complex words, and like Group 1, they outperformed Group 2 on this measure. However, Group 3 did not perform significantly better than Group 2 on nonword decoding, and both of these groups performed significantly more poorly than Group 1 on this measure. There were no group differences in the ability to orally generate base words. Conclusion: Children with a history of speech impairment who had received phonological awareness intervention and who became proficient readers demonstrated an ability to use morphological awareness in the spelling… [ABSTRACT FROM AUTHOR]
Phonological Processing Skills of Adolescents With Residual Speech Sound Errors
from Language, Speech, and Hearing Services in Schools
Purpose: Research has shown that young children with speech sound disorders may have weaknesses in phonological processing. However, such skills have not been thoroughly examined in adolescents with residual speech sound errors. Therefore, this study compared the phonological processing abilities of adolescents with residual speech sound errors to those of normally speaking peers. Method: Two nonword repetition tasks, multisyllabic word repetition, spoonerisms, phoneme reversals, and an elision task were used to compare the phonological processing skills of 10-14-year-olds with residual speech sound errors that include rhotic phonemes (RE, n = 13) to those of normally speaking (NS, n = 14) adolescents of similar age and receptive vocabulary abilities. Results: The 2 groups were found to differ on 5 of the 6 phonological processing tasks. Discriminant analysis showed that 85% of the participants could be correctly classified into the RE and NS groups based solely on phonological processing skills. Conclusion: The possible nature of the phonological processing impairment is discussed in the context of current theoretical understanding. It is recommended that when planning assessment and intervention for adolescents with residual speech sound errors, clinicians be cognizant of the fact that the adolescents may also have weaknesses in phonological processing. [ABSTRACT FROM AUTHOR]
About the Callier Library
Callier Library is a satellite facility of The University of Texas at Dallas, McDermott Library. It is located at the Dallas, Texas campus of the Callier Center for Communication Disorders. The library supports the graduate-level programs and faculty in communications sciences which are located at the center. It also supports the work of clinicians in hearing and speech disorders who work at both campuses of the Callier Center. One of the missions of Callier Library is to be a useful source of information to the international community of researchers and clinicians in communication disorders. To that end, this web log of citations and news in the field has been built and maintained by Allen Clayton, the Callier Center Librarian.
Note: These news items are gleaned from over 400 sources on the Internet and are provided as a service to our patrons. The University of Texas at Dallas does not guarantee the veracity, reliability or completeness of any information provided on this page, or in any hyperlink appearing on this page
