Monthly Archives: August 2011
Modeling Abnormal Priming in Alzheimer’s Patients with a Free Association Network
Alzheimer’s Disease irremediably alters the proficiency of word search and retrieval processes even at its early stages. Such disruption can sometimes be paradoxical in specific language tasks, for example semantic priming. Here we focus in the striking side-effect of hyperpriming in Alzheimer’s Disease patients, which has been well-established in the literature for a long time. Previous studies have evidenced that modern network theory can become a powerful complementary tool to gain insight in cognitive phenomena. Here, we first show that network modeling is an appropriate approach to account for semantic priming in normal subjects. Then we turn to priming in degraded cognition: hyperpriming can be readily understood in the scope of a progressive degradation of the semantic network structure. We compare our simulation results with previous empirical observations in diseased patients finding a qualitative agreement. The network approach presented here can be used to accommodate current theories about impaired cognition, and towards a better understanding of lexical organization in healthy and diseased patients.
from PLoS ONE
Evidence for Catch-up in Cognition and Receptive Vocabulary Among Adolescents Born Very Preterm
CONCLUSIONS: Significant catch-up in receptive vocabulary is observed by the age of 16 years among very preterm children compared to term peers. The absence of neurosensory impairment and residing in a favorable socioeconomic milieu are associated with the most optimal developmental trajectories.
from Pediatrics
Mode of Communication, Perceived Level of Understanding, and Perceived Quality of Life in Youth Who Are Deaf or Hard of Hearing
Given the important role of parent–youth communication in adolescent well-being and quality of life, we sought to examine the relationship between specific communication variables and youth perceived quality of life in general and as a deaf or hard-of-hearing (DHH) individual. A convenience sample of 230 youth (mean age = 14.1, standard deviation = 2.2; 24% used sign only, 40% speech only, and 36% sign + speech) was surveyed on communication-related issues, generic and DHH-specific quality of life, and depression symptoms. Higher youth perception of their ability to understand parents’ communication was significantly correlated with perceived quality of life as well as lower reported depressive symptoms and lower perceived stigma. Youth who use speech as their single mode of communication were more likely to report greater stigma associated with being DHH than youth who used both speech and sign. These findings demonstrate the importance of youths’ perceptions of communication with their parents on generic and DHH-specific youth quality of life.
Reading and Reading-Related Skills in Children Using Cochlear Implants: Prospects for the Influence of Cued Speech
We assessed the reading and reading-related skills (phonemic awareness and phonological short-term memory) of deaf children fitted with cochlear implants (CI), either exposed to cued speech early (before 2 years old) (CS+) or never (CS–). Their performance was compared to that of 2 hearing control groups, 1 matched for reading level (RL), and 1 matched for chronological age (CA). Phonemic awareness and phonological short-term memory were assessed respectively through a phonemic similarity judgment task and through a word span task measuring phonological similarity effects. To assess the use of sublexical and lexical reading procedures, children read pseudowords and irregular words aloud. Results showed that cued speech improved performance on both the phonemic awareness and the reading tasks but not on the phonological short-term memory task. In phonemic awareness and reading, CS+ children obtained accuracy and rapidity scores similar to CA controls, whereas CS– children obtained lower scores than hearing controls. Nevertheless, in phonological short-term memory task, the phonological similarity effect of both CI groups was similar. Overall, these results support the use of cued speech to improve phonemic awareness and reading skills in CI children.
Semantic and Pragmatic Factors Influencing Deaf and Hearing Students’ Comprehension of English Sentences Containing Numeral Quantifiers
This research contrasted deaf and hearing students’ interpretive knowledge of English sentences containing numeral quantifier phrases and indefinite noun phrases. A multiple-interpretation picture task methodology was used to assess 305 participants’ judgments of the compatibility of sentence meanings with depicted discourse contexts. Participants’ performance was assessed on the basis of hearing level (deaf, hearing) and grade level (middle school, high school, college). The deaf students were predicted to have differential access to specific sentence interpretations in accordance with the relative derivational complexity of the targeted sentence types. Hypotheses based on the pressures of derivational economy on acquisition were largely supported. The results also revealed that the deaf participants tended to overactivate pragmatic processes that yielded principled, though non-target, sentence interpretations. Collectively, the results not only contribute to the understanding of English acquisition under conditions of restricted access to spoken language input, they also suggest that pragmatic factors may play a broad role in influencing, and compromising, deaf students’ reading comprehension and written expression.
Social Participation of Children and Adolescents With Cochlear Implants: A Qualitative Analysis of Parent, Teacher, and Child Interviews
Psychosocial factors, including socioemotional well-being, peer relationships, and social inclusion with hearing and deaf peers, are increasingly becoming a focus of research investigating children with cochlear implants. The study reported here extends the largely quantitative findings of previous research through a qualitative analysis of interviews with parents, teachers, and pediatric cochlear implant users themselves in three eastern states of Australia. We interviewed 24 parents, 15 teachers, and 11 children and adolescents. The findings displayed commonalities across the three groups of participants, indicating positive experiences around the children’s psychosocial development with their cochlear implants, but also ongoing difficulties communicating in groups of people and problems related to social skills. Some children had little contact with other deaf children (with or without cochlear implants) despite parents and teachers perceiving such contact beneficial. Children attending schools where there were other deaf children valued friendships with both deaf and hearing peers. Adolescence was a particularly difficult time for some as they struggled with feelings of self-consciousness about their deafness and external cochlear implant equipment and worries around friendships, dating, and their future place in the world. Recommendations for practice and further research are made.
Strategies for Teaching Writing to Deaf College Students
The teaching of X-Word Grammar will appeal to writing instructors and tutors who work with deaf college students. Livingston, the author, created an engaging instructional handbook that aims to make teaching English simple and less complicated. X-Word Grammar is a revising technique that derives from the work of Allen (1967). Allen’s original system was Sector Analysis and was adapted into X-Word Grammar. The letter “X” stands for auXiliary as in auxiliary verbs (“be,” “do,” “have,” and all the modals). Livingston has taught developmental writing for many years in the Program for Deaf Adults at LaGuardia Community College. Eight years ago, she was introduced to X-Word Grammar through a colleague and had seen positive development in her students’ working texts.
An Investigation to Validate the Grammar and Phonology Screening (GAPS) Test to Identify Children with Specific Language Impairment
Conclusions
The findings reveal that the GAPS is highly accurate in identifying impaired vs. non-impaired children up to 6;8 years, and has moderate-to-high accuracy up to 9 years. The results indicate that GAPS is a realistic tool for the early identification of grammatical abilities and impairment in young children. A larger investigation is warranted in children with SLI and other developmental disorders.
from PLoS ONE
Deleterious sucking habits and atypical swallowing in children with otitis media with effusion
Conclusions
Our data suggest a correlation between otitis media with effusion, deleterious sucking habits and prevalence of atypical swallowing.
from the International Journal of Pediatric Otorhinolaryngology
Performance of two hearing screening protocols in NICU in Shanghai
Conclusion
Our study demonstrates the use of a combination of DPOAE and AABR testing ensures high sensitivity and acceptable specificity, and predict the AN profile in NICU babies. Our efforts identified 22 NICU babies with auditory neuropathy who hopefully will benefit from early remediation of their hearing deficit.
from the International Journal of Pediatric Otorhinolaryngology
Vestibular information is necessary for maintaining metric properties of representational space: Evidence from mental imagery
The vestibular system contributes to a wide range of functions, from postural and oculomotor reflexes to spatial representation and cognition. Vestibular signals are important to maintain an internal, updated representation of the body position and movement in space. However, it is not clear to what extent they are also necessary to mentally simulate movement in situations that do not involve displacements of the body, as in mental imagery. The present study assessed how vestibular loss can affect object-based mental transformations (OMTs), i.e., imagined rotations or translations of objects relative to the environment. Participants performed one task of mental rotation of 3D-objects and two mental scanning tasks dealing with the ability to build and manipulate mental images that have metric properties. Menière’s disease patients were tested before unilateral vestibular neurotomy and during the recovery period (1 week and 1 month). They were compared to healthy participants tested at similar time intervals and to bilateral vestibular-defective patients tested after the recovery period. Vestibular loss impaired all mental imagery tasks. Performance varied according to the extent of vestibular loss (bilateral patients were frequently the most impaired) and according to the time elapsed after unilateral vestibular neurotomy (deficits were stronger at the early stage after neurotomy and then gradually compensated). These findings indicate that vestibular signals are necessary to perform OMTs and provide the first demonstration of the critical role of vestibular signals in processing metric properties of mental representations. They suggest that vestibular loss disorganizes brain structures commonly involved in mental imagery, and more generally in mental representation.
from Neuropsychologia
Narrow noise band detection in a complex masker: Masking level difference due to harmonicity
Three experiments investigated listeners’ ability to detect a narrow band of noise, centered on one partial of a random phase complex tone, as a function of inharmonicity. Inharmonicity was generated by randomly mistuning the partial frequencies from a 100-Hz fundamental frequency (F0). In experiment 1, masked detection thresholds were lower when the masker was harmonic than when it was inharmonic for target bands in the range 0.5-2.5 kHz. The presence of this masking level difference due to harmonicity (HMLD) in regions of resolved partials and the reduction of the HMLD with increasing center frequency did not support the idea that HMLD was primarily caused by the envelope modulations produced by the beating of unresolved partials within an auditory filter. In experiment 2, masker mistunings ranging beyond 12% of the F0 disrupted the HMLD while smaller mistunings gave thresholds similar to a harmonic masker. In experiment 3, all partials contributed to some extent to the HMLD, but the harmonicity of partials neighboring the target had a greater influence than distant partials. The observed HMLDs can best be accounted for by a mechanism of harmonic cancellation.
from Hearing Research
Competition between word order and case-marking in interpreting grammatical relations: a case study in multilingual acquisition
The study examines strategies multilingual children use to interpret grammatical relations, focusing on their two primary languages, Lajamanu Warlpiri and Light Warlpiri. Both languages use mixed systems for indicating grammatical relations. In both languages ergative–absolutive case-marking indicates core arguments, but to different extents in each language. In Lajamanu Warlpiri, pronominal clitics in a nominative–accusative pattern also indicate core arguments, and in Light Warlpiri word order in a nominative–accusative pattern partially does so. The study asks which sentence interpretation strategies children rely on most, when they learn to rely on them and whether cross-linguistic influences are seen. Children aged 5 ; 0, 7 ; 0 and 9 ; 0 and adults saw paired, animated events simultaneously on video and heard a transitive sentence spoken. The participants pointed to the event depicted by the sentence heard. Adults used a case-marking strategy consistently in both languages. Children initially used both case-marking and word order strategies, but used case-marking more often as age increased.
from the Journal of Child Language
Do newly formed word representations encode non-criterial information?
Lexical stress is useful for a number of language learning tasks. In particular, it helps infants segment the speech stream and identify phonetic contrasts. Recent work has demonstrated that infants aged 1 ; 0 can learn two novel words differing only in their stress pattern. In the current study, we ask whether infants aged 1 ; 0 store stress information in their representations of words even when it not required for the task. To this end, we taught infants novel, three-syllable word–object pairings. At test, we manipulated the word by presenting infants with forms that shared the stress pattern of the familiar words but differed in the segments, and forms that shared the segments of the familiar word but differed in the stress pattern. Our findings reveal that infants’ representations of new words include word-level stress information and do not simply contain the information critical for distinguishing between different forms.
from the Journal of Child Language
Information tracking and encoding in early L1: linguistic competence vs. cognitive limitations
This study provides experimental evidence for preschool children’s competence in basic information structure, with particular attention to the notions of topic and focus. It investigates their mastery of structural and definiteness distinctions to encode the information status of discourse referents, and seeks to distinguish linguistic competence from cognitive development as the source for children’s ‘errors’. Evidence comes from a story-telling experiment performed on 45 children acquiring French (between the ages of 2 ; 6·22 and 5 ; 6·15). The article demonstrates continuity between the child and adult systems of basic discourse representation. It further argues that children’s definiteness errors are not due to a lack of knowledge of the adult rules of information encoding. Rather, such errors stem from cognitive limitations and from assuming a wider common ground than adults would.
from the Journal of Child Language
