What Do Second Language Listeners Know About Spoken Words? Effects of Experience and Attention in Spoken Word Processing

from the Journal of Psycholinguistic Research

Abstract With a goal of investigating psycholinguistic bases of spoken word processing in a second language (L2), this study examined L2 learners’ sensitivity to phonological information in spoken L2 words as a function of their L2 experience and attentional demands of a learning task. Fifty-two Chinese learners of English who differed in amount of L2 experience (longer vs. shorter residence in L2 environment) were tested in an auditory word priming experiment on well-known L2 words under two processing orientation conditions (semantic, control). Results revealed that, with more L2 experience, learners become more sensitive to phonological detail in spoken L2 words but that attention to word meaning might eliminate this sensitivity, even for learners with more L2 experience.

Simultaneous and Sequential Bilateral Sudden Sensorineural Hearing Loss: Are They Different from Unilateral Sudden Sensorineural Hearing Loss?

from ORL -Journal for Oto-Rhino-Laryngology and Its Related Specialties

Aim: To compare bilateral (BSSHL) with unilateral (USSHL) sudden sensorineural hearing loss. Methods and Subjects: Two hundred and thirty-two patients with USSHL, 11 with simultaneous BSSHL and 7 with sequential BSSHL, who were older than 15 years had onset of hearing loss <30 days, no head injuries or history of acoustic trauma. All patients received the same treatment (prednisolone). Results: Hearing loss was more severe in simultaneous BSSHL in comparison to sequential BSSHL (p = 0.01) or USSHL (p = 0.03). Autoimmune diseases were far more common in simultaneous BSSHL (36% of patients) than USSHL. Positive antinuclear antibody was found in half of BSSHL patients and in only 8% of unilateral cases (p = 0.01). The frequency of hearing improvement was much lower in simultaneous BSSHL than in USSHL (p = 0.001). Complete or partial improvement was noted in 74% of unilateral cases versus 27% in simultaneous bilateral cases. Patients with sequential BSSHL improved in a similar way to unilateral cases. Conclusions: Simultaneous BSSHL, sequential BSSHL and USSHL may have a completely different profile and should not be managed as one disease. Hearing loss, underlying autoimmune diseases, antinuclear antibodies, and improvement/recovery of hearing loss vary in a degree that implies different pathophysiology and prognosis.

Speaking with a single cerebral hemisphere: fMRI language organization after hemispherectomy in childhood

from Brain and Language

Speech-related fMRI activation was examined in six hemispherectomy patients (three left LX, three right RX, four with congenital and two with late-acquired hemiplegia) operated in childhood for the relief of drug-resistant epilepsy. Although the temporal and sensorimotor pattern of activation was similar to that found in neurologically intact control participants, activation in Broca’s area and its right homolog varied greatly. Involvement of pars triangularis and orbitalis was found in the three cases with best outcome (two RX, one LX), whereas pars opercularis alone was activated in the two remaining LX patients. The results suggest that distinct subregions of Broca’s area and their right homologs can subserve speech and language, and that this variability may determine functional outcome.

Bird Brains Suggest How Vocal Learning Evolved

from Medical News Today.com

Though they perch far apart on the avian family tree, birds with the ability to learn songs use similar brain structures to sing their tunes. Neurobiologists at Duke University Medical Center now have an explanation for this puzzling likeness.

Development of an instrument to evaluate audiologic counseling skills

from the Journal of the American Academy of Audiology

This study describes the development of an instrument designed to evaluate audiologic counseling skills. In simulated counseling sessions, a trained actor portrayed a parent, and ten graduate audiology students role-played counseling sessions as audiologists informing the “parent” that her infant has a hearing loss. The ten sessions were videotaped, and three raters viewed the taped sessions while evaluating counseling skills with a new evaluation tool, the Audiologic Counseling Evaluation (ACE). The ACE was found to have excellent internal reliability (alpha = .91) and moderate-to-good inter-rater reliability. Raters’ subjective evaluations of the tool were generally positive, and students’ evaluations of the simulated counseling experience were overwhelmingly so. This instrument can be used by audiology faculty and clinical instructors to help students improve their counseling skills before interacting with parents. It can also be used in clinical settings for professional development by way of self- and peer-evaluation.

Effect of frequency boundary assignment on speech recognition with the Nucleus 24 ACE speech coding strategy

from the Journal of the American Academy of Audiology

The choice of frequency boundaries for the analysis channels of cochlear implants has been shown to impact the speech perception performance of adult recipients (Skinner et al, 1995; Fourakis et al, 2004). While technological limitations heretofore have limited the clinical feasibility of investigating novel frequency assignments, the SPEAR3 research processor affords the opportunity to investigate an unlimited number of possibilities. Here, four different assignments are evaluated using a variety of speech stimuli. All participants accommodated to assignment changes, and no one assignment was significantly preferred. The results suggest that better performance can be achieved using a strategy whereby (1) there are at least 7-8 electrodes allocated below 1000 Hz, (2) the majority of remaining electrodes are allocated between 1100-3000 Hz, and (3) the region above 3 kHz is represented by relatively few electrodes (i.e., 1-3). The results suggest that such frequency assignment flexibility should be made clinically available.

Effects of cigarette smoking on distortion product otoacoustic emissions

from the Journal of the American Academy of Audiology

This study measured distortion product otoacoustic emissions (DPOAEs) and DPOAE input/output (I/O) curves to assess the effects of smoking on cochlear function. Twenty-four healthy adults, 12 smokers and 12 nonsmokers in the 20-30 years age range were selected based on self-reported histories of five to eight years of smoking or no smoking, respectively. All subjects received tympanometric screening to rule out middle ear pathology. Conventional (0.25-8 kHz) and ultra high frequency (UHF; 10-20 kHz) audiometry showed normal or age-appropriate thresholds across both groups. DPOAE results showed small, but significant, decline in DPOAE levels without concomitant changes in noise floors in smokers as compared to nonsmokers. I/O detection thresholds were also significantly elevated at high frequencies in smokers as compared to their nonsmoking counterparts. These findings indicate that smokers are at greater risk for cochlear damage than nonsmokers, and that DPOAE amplitudes and I/O detection thresholds may identify early changes in cochlear function in smokers.

Speech and music quality ratings for linear and nonlinear hearing aid circuitry

from the Journal of the American Academy of Audiology

This study evaluated quality ratings for speech and music stimuli processed using peak clipping (PC), compression limiting (CL), and wide-dynamic range compression (WDRC) hearing aid circuitry. Eighteen listeners with mild-to-moderate hearing loss were binaurally fitted with behind-the-ear (BTE) hearing aids and instructed to rate the quality of speech under various conditions in quiet and noise and two genres of music. Results for speech revealed a slight preference for WDRC at 80 dB SPL, and equivalent ratings for the three circuits under all other listening conditions. Music ratings revealed a marginally significant preference for WDRC and a preference for classical over popular music. For music, judgments on pleasantness were the most influential on overall circuit preference.

The objective and subjective evaluation of low-frequency expansion in wide dynamic range compression hearing instruments

from the Journal of the American Academy of Audiology

The effects of low-frequency expansion on the objective and subjective evaluation of four channel in-the-ear hearing instruments was investigated. Three expansion settings were programmed in each device: expansion off, expansion restricted to channel one, and expansion restricted to channels one and two. Objective evaluations were conducted in quiet (Connected Speech Test) and in noise (Hearing in Noise Test) with speech levels fixed at 40 dB SPL. Subjectively, each participant rated expansion satisfaction in quiet and listening to low-level speech in a sound-treated room then indicated the expansion condition preferred overall. Listeners performed significantly better in quiet and in noise for the Off and Channel 1 conditions than the Channels 1 and 2 condition; however, performance was similar between the Off and Channel 1 conditions. Expansion effects on listener satisfaction ratings depended on the listening environment. Overall, listeners preferred expansion in Channel 1 to expansion in Channels 1 and 2; however, preference was not significantly different between the Channel 1 and Off conditions. Results indicate restricting expansion to 1000 Hz overcomes speech-recognition deficits observed with expansion active across a broader spectrum without significantly reducing subjective benefit or preference.

The value of routine real ear measurement of the gain of digital hearing aids

from the Journal of the American Academy of Audiology

The main aims of this study were: (1) to determine whether routine real ear insertion gain (REIG) measurement is necessary in fitting digital hearing aids; and (2) to assess the extent to which modifying the frequency-gain response of an aid can lead to better matches to the target in cases where the target gain was not initially achieved. The target formula was selected as NAL-NL1 in the programming software of four types of digital hearing aids. REIG measurements on 42 ears showed that 64% of cases failed to come within +/-10 dB of the target at one or more of the following frequencies: 0.25, 0.5, 0.75, 1, 1.5, 2, and 4 kHz. After adjusting the frequency-gain response of the aids, based on the REIG results, 83% of cases came within +/-10 dB of the target. The target was met more often, both before and after adjustment, for aids with seven gain “handles” than for aids with four gain “handles”. The results indicate that REIG measurements can and should be used to achieve more accurate fittings but that accurate adjustments are difficult with some aids.

Identical neural risk factors predict cognitive deficit in dyslexia and schizophrenia

fromNeuropsychology

In previous work, the authors found that an anatomical risk index created from the combination of 7 neuroanatomical measures predicted reading and oral language skills in individuals with learning disabilities. Individuals with small auditory brain structures and reduced asymmetry had more deficits than those with large structures and exaggerated asymmetry. In the present study, the same anatomical index predicted reading and other cognitive abilities in 45 individuals with chronic schizophrenia. The anatomical risk index was significantly associated with broad cognitive ability (Pearson r = .53, p < .0001), reading comprehension (r = .58, p < .0001), and a measure of nonverbal reasoning (r = .39, p < .01), but not with age, parental socioeconomic status, symptom measures, alcohol use, or processing speed. These findings support the prediction that reduced size and asymmetry in temporal lobe auditory cortex and cerebellum may not be specific risk factors for schizophrenia but for cognitive deficits that characterize a broad spectrum of developmental disorders. (PsycINFO Database Record (c) 2008 APA, all rights reserved)

The effectiveness of N-acetyl-l-cysteine (l-NAC) in the prevention of severe noise-induced hearing loss

from Hearing Research

Three groups of chinchillas were exposed to a nonGaussian continuous broadband noise at an Leq = 105 dB SPL, 8 h/d for 5 d. One group (N = 6) received only the noise. A second group (N = 6) received the noise and was additionally treated with l-NAC (325 mg/kg, i.p.). Treatment was administered twice daily for 2 d prior to exposure and for 2 d following the exposure. During exposure the animals received the l-NAC just prior to and immediately after each daily exposure. The third group (N = 4) was exposed to the noise and received saline injections on the same schedule as the l-NAC treated animals. Auditory evoked potential recordings from the inferior colliculus were used to estimate pure tone thresholds and surface preparations of the organ of Corti quantified the sensory cell population. In all three groups PTS exceeded 50 dB at 2.0 kHz and above with severe sensory cell loss in the basal half of the cochlea. There was no statistically significant difference among the three groups in all measures of noise-induced trauma. Treatment with l-NAC did not reduce the trauma produced by a high-level, long duration, broadband noise exposure.

Intervention for children with language impairments: a model of evidence-based outcome research

from theJournal of Research in Special Educational Needs

Over the past 30 years successive governments in the UK have endeavoured to make the statutory framework suitable for children with special educational needs (SEN). More recently, efforts have been made to personalise children’s learning, making educational experience more innovative and responsive to the diversity of needs in schools. A drive is emerging in health and education to develop and evaluate intervention strategies for children with language impairments (LIs), which is both methodologically challenging and rewarding. The current review demonstrates difficulties encountered with using evidence-based (evidence-related) outcome research involving children with LIs. Many studies have inherent methodological problems such as small sample sizes, ill-matched groups and designs that are difficult to replicate or compare. Such approaches are unlikely to yield significant results, or if they do, it is difficult to devise clear guidance regarding choice of intervention strategies. In the light of these difficulties, theoretical, methodological and practical issues are discussed herein and a model is proposed to assist in enabling interventions to be identified, evaluated in a robust manner, and the results shared with educators. We suggest that the use of a process-driven model ensures a more rigorous approach when undertaking large-scale systematic, evidence-based research into the effective approaches to teaching children not only with LIs but across the field of special needs education.

Dyslexia in Greek higher education: a study of incidence, policy and provision

from theJournal of Research in Special Educational Needs

Dyslexia is defined as a disability that primarily affects reading and writing. Internationally, the number of dyslexic students entering higher education is on the rise. It is estimated that students with dyslexia represent a small but significant minority. Many English-speaking countries have developed support services and teaching practices to accommodate dyslexic students’ educational needs. In Greece, research on dyslexia is very limited. The purpose of this study is to define the incidence of dyslexia among the Greek student population and to examine dyslexic students’ age, gender and major field of study. Data were collected from a total of 406 departments at all Greek public institutions of higher education (n = 32). The existing practices for identifying and provisions for supporting dyslexic students were also examined. The incidence of dyslexia in Greek higher education was estimated to be 0.16%, which is far below the estimated incidence in the general population. Interesting results were yielded regarding the variability of higher education institutions’ responses to dyslexia. In almost all Greek institutions, provision takes place in the form of oral examinations and generic counseling. technological education institutions (TEIs) seem to be more aware of the educational needs of dyslexic students, possibly because they have three times more dyslexic students than higher education institutions (HEIs). All Greek universities deal with the needs of dyslexic students on an individual basis, making provision reactive rather than proactive. The results of the present study are discussed in the light of inclusive education and equality of opportunity for students who learn in a different way but do not differ from their counterparts in terms of intelligence or general abilities.

Metacognitive strategies applied during correcting text-related answers of three students with hearing loss

from theJournal of Research in Special Educational Needs

The purpose of this paper is to describe the metacognitive strategies applied during the controlling–correcting activities of three hearing-impaired youths’ written answers to text-related questions. The data have been derived from a pilot action research effort. The research journal, students’ portfolios, archival information, interviews, surveys and the videotaped data of this action research effort have been compiled based on the cyclical actions and analysed inductively. The metacognitive strategies the instructor applied seemed to create a supportive environment for the students to contribute to the activity, utilising some of their metacognitive strategies and skills. However, it is suggested that for their internalisation of those metacognitive strategies, they would need more practice and various experiences in meaningful learning environments.

Social engagement, attention and competence of preschoolers with hearing loss

from theJournal of Research in Special Educational Needs

The social engagement, social attention skills and social competence of 10 hearing preschoolers and 10 preschoolers with hearing loss were investigated during free play in inclusive oral kindergarten settings using a three-level hierarchical model. When comparing the types of opportunities, at the first level, the children with hearing loss created significantly fewer opportunities through visual regard and interaction. At the second level, for social attention skills, this group scored significantly higher on distractibility, and significantly lower on alert, sustained and focused attention. For the third level, social competence, no statistically significant differences were found between the two groups. Discriminant Function Analysis showed that the function that discriminated maximally between the two groups of participants was composed only of amount of interaction at Level 1. Children scoring highly on this function were also more likely to have the ability to focus their attention and manage divided attention, to be reciprocal, and to demonstrate mutuality and problem-solving skills with peers.

Language affects patterns of brain activation associated with perceptual decision

from the Proceedings of the National Academy of Sciences of the United States of America

Well over half a century ago, Benjamin Lee Whorf [Carroll JB (1956) Language, Thought, and Reality: Selected Writings of Benjamin Lee Whorf (MIT Press, Cambridge, MA)] proposed that language affects perception and thought and is used to segment nature, a hypothesis that has since been tested by linguistic and behavioral studies. Although clear Whorfian effects have been found, it has not yet been demonstrated that language influences brain activity associated with perception and/or immediate postperceptual processes (referred hereafter as “perceptual decision”). Here, by using functional magnetic resonance imaging, we show that brain regions mediating language processes participate in neural networks activated by perceptual decision. When subjects performed a perceptual discrimination task on easy-to-name and hard-to-name colored squares, largely overlapping cortical regions were identified, which included areas of the occipital cortex critical for color vision and regions in the bilateral frontal gyrus. Crucially, however, in comparison with hard-to-name colored squares, perceptual discrimination of easy-to-name colors evoked stronger activation in the left posterior superior temporal gyrus and inferior parietal lobule, two regions responsible for word-finding processes, as demonstrated by a localizer experiment that uses an explicit color patch naming task. This finding suggests that the language-processing areas of the brain are directly involved in visual perceptual decision, thus providing neuroimaging support for the Whorf hypothesis.

A Common Neural Network for Cognitive Reserve in Verbal and Object Working Memory in Young but not Old

from Cerebral Cortex

Epidemiologic evidence suggests that cognitive reserve (CR) mitigates the effects of aging on cognitive function. The goal of this study was to see whether a common neural mechanism for CR could be demonstrated in brain imaging data acquired during the performance of 2 tasks with differing cognitive processing demands. Young and elder subjects were scanned with functional magnetic resonance imaging (fMRI) while performing a delayed item response task that used either letters (40 young, 18 old) or shapes (24 young, 21 old). Difficulty or load was manipulated by varying the number of stimuli that were presented for encoding. Load-dependent fMRI signal corresponding to each trial component (stimulus presentation, retention delay, and probe) and task (letter or shape) was regressed onto 2 putative CR variables. Canonical variates analysis was applied to the resulting maps of regression coefficients, separately for each trial component, to summarize the imaging data—CR relationships. There was a latent brain pattern noted in the stimulus presentation phase that manifested similar relationships between load-related encoding activation and CR variables across the letter and shape tasks in the young but not the elder age group. This spatial pattern could represent a general neural instantiation of CR that is affected by the aging process.

A Larynx Area in the Human Motor Cortex

from Cerebral Cortex

The map of the human motor cortex has lacked a representation for the intrinsic musculature of the larynx ever since the electrical stimulation studies of Penfield. In addition, there has been no attempt to localize this area using neuroimaging techniques. Because of the central importance of laryngeal function to vocalization, we sought to localize an area controlling the intrinsic muscles of the larynx by using functional magnetic resonance imaging and to place this area in a somatotopic context. We had subjects perform a series of oral tasks designed to isolate elementary components of phonation and articulation, including vocalization of a vowel, lip movement, and tongue movement. In addition, and for the first time in a neuroimaging study, we had subjects perform “glottal stops,” in other words forced closure of the glottis in the absence of vocalizing. The results demonstrated a larynx-specific area in the motor cortex that is activated comparably by vocal and nonvocal laryngeal tasks. Converging evidence suggests that this area is the principal vocal center of the human motor cortex. Finally, the location of this larynx area is strikingly different from that reported in the monkey. We discuss the implications of this observation for the evolution of vocal communication in humans.

The Relationship between Study Processing and the Effects of Cue Congruency at Retrieval: fMRI Support for Transfer Appropriate Processing

from Cerebral Cortex

Using functional magnetic resonance imaging, the present study investigated whether the enhanced memory performance associated with congruent relative to incongruent retrieval cues is modulated by how items are encoded. Subjects studied a list of visually presented words and pictures and attempted to recognize these items in a later memory test. Half of the studied items were tested with a congruent cue (word–word and picture–picture), whereas the remainders were tested with an incongruent cue (word–picture and picture–word). For both words and pictures, regions where study activity was greater for congruently than incongruently cued items overlapped regions where activity differentiated the 2 classes of study material. Thus, word congruency effects overlapped regions where activity elicited by study words exceeded the activity elicited by pictures. Similarly, picture congruency effects overlapped regions demonstrating enhanced activity for pictures relative to words. In addition, several regions, including dorsolateral prefrontal cortex and intraparietal sulcus, demonstrated material-nonspecific congruency effects. The findings suggest that items benefit from a congruent retrieval cue when their study processing resembles the processing later engaged by the retrieval cue. Consistent with the principle of transfer appropriate processing, the benefit of a congruent retrieval cue derives from the interaction between study and retrieval processing.

Visual Scenes Trigger Immediate Syntactic Reanalysis: Evidence from ERPs during Situated Spoken Comprehension

from Cerebral Cortex

A central topic in sentence comprehension research is the kinds of information and mechanisms involved in resolving temporary ambiguity regarding the syntactic structure of a sentence. Gaze patterns in scenes during spoken sentence comprehension have provided strong evidence that visual scenes trigger rapid syntactic reanalysis. However, they have also been interpreted as reflecting nonlinguistic, visual processes. Furthermore, little is known as to whether similar processes of syntactic revision are triggered by linguistic versus scene cues. To better understand how scenes influence comprehension and its time course, we recorded event-related potentials (ERPs) during the comprehension of spoken sentences that relate to depicted events. Prior electrophysiological research has observed a P600 when structural disambiguation toward a noncanonical structure occurred during reading and in the absence of scenes. We observed an ERP component with a similar latency, polarity, and distribution when depicted events disambiguated toward a noncanonical structure. The distributional similarities further suggest that scenes are on a par with linguistic contexts in triggering syntactic revision. Our findings confirm the interpretation of previous eye movement studies and highlight the benefits of combining ERP and eye-tracking measures to ascertain the neuronal processes enabled by, and the locus of attention in, visual contexts.

Volume of Left Heschl’s Gyrus and Linguistic Pitch Learning

from Cerebral Cortex

Research on the contributions of the human nervous system to language processing and learning has generally been focused on the association regions of the brain without considering the possible contribution of primary and adjacent sensory areas. We report a study examining the relationship between the anatomy of Heschl’s Gyrus (HG), which includes predominately primary auditory areas and is often found to be associated with nonlinguistic pitch processing and language learning. Unlike English, most languages of the world use pitch patterns to signal word meaning. In the present study, native English-speaking adult subjects learned to incorporate foreign pitch patterns in word identification. Subjects who were less successful in learning showed a smaller HG volume on the left (especially gray matter volume), but not on the right, relative to learners who were successful. These results suggest that HG, typically shown to be associated with the processing of acoustic cues in nonspeech processing, is also involved in speech learning. These results also suggest that primary auditory regions may be important for encoding basic acoustic cues during the course of spoken language learning.

Grappling with grammar

from EurekAlert.org

Researchers at UCL (University College London) have discovered that a system in the brain for processing grammar is impaired in some children with specific language impairment (SLI), but that these children compensate with a different brain area. The findings offer new hope for sufferers of SLI, which affects seven per cent of children and is a major cause of many not reaching their educational potential. To date, it has not been clear whether these children generally struggle to process language, or whether they have specific problems with grammar. The UCL findings reveal the latter for a sub-group (G-SLI), and suggest that educational methods that enhance these compensatory mechanisms may help such children overcome their difficulties.

Contextual integration the unusual way: a magnetoencephalographic study of responses to semantic violation in individuals with autism spectrum disorders

from the European Journal of Neuroscience

Autism is a neurodevelopmental disorder associated with deficits in language and social communication. Behavioural studies indicate abnormal semantic organization in individuals with autism, but little is known about the neural mechanism underlying the processing of language in context. Magnetoencephalography was used to record neural responses in 11 able adults with autism spectrum disorders reading meaningful sentences and sentences ending with a semantically incongruous word (e.g. ‘He sent a photo to the trumpet’). Spatially extended evoked signals at 400 ms (N4) and 750 ms (LPC), as well as synchronized gamma-oscillations, provided clear evidence for specific neuronal processes sensitive to sentence context that differed in individuals with autism compared with typically developing individuals (11 healthy volunteers). Amongst other differences, N4 responses following incongruous words were weaker over left temporal cortices, whereas LPC responses to incongruous words and long-latency gamma-oscillations following congruous words were stronger over central and prefrontal regions in individuals with autism compared with the control group. Also, incongruous words elicited long-lasting gamma-oscillations above 40 Hz in the clinical group, but not in typically developing subjects. These findings may indicate unusual strategies for resolving semantic ambiguity in autism. Moreover, the observed gamma-band responses provide evidence for sustained cortical synchronization across segregated areas in individuals with autism, contrary to claims that a general deficit in either temporal binding or long-range connectivity may explain autism.

Atypical neural functions underlying phonological processing and silent rehearsal in children who stutter

from Developmental Science

Phonological processing was examined in school-age children who stutter (CWS) by assessing their performance and recording event-related brain potentials (ERPs) in a visual rhyming task. CWS had lower accuracy on rhyming judgments, but the cognitive processes that mediate the comparisons of the phonological representations of words, as indexed by the rhyming effect (RE) ERP, were similar for the stuttering and normally fluent groups. Thus the lower behavioral accuracy of rhyming judgments by the CWS could not be attributed to that particular stage of processing. Instead, the neural functions for processes preceding the RE, indexed by the N400 and CNV elicited by the primes and the N400 elicited by the targets, suggest atypical processing that may have resulted in less efficient, less accurate rhyming judgment for the CWS. Based on the present results, it seems likely that the neural processes related to phonological rehearsal and target word anticipation, as indexed by the CNV, are distinctive for CWS at this age. Further, it is likely that the relative contributions of the left and right hemispheres differ in CWS in the stage of processing when linguistic integration occurs, as indexed by the N400. Taken together, these results suggest that CWS may be less able to form and retain a stable neural representation of the prime onset and rime as they anticipate the target presentation, which may lead to lower rhyming judgment accuracy.

Plasma antidiuretic hormone in cases with the early onset of profound unilateral deafness

from Auris Nasus Larynx

OBJECTIVE: The p-ADH level in cases of juvenile unilateral profound deafness (JUPD) and the timecourse of the level were examined to investigate whether or not an increase of p-ADH is involved in the development of delayed endolymphatic hydrops (DEH) in JUPD. MATERIALS AND METHODS: In 90 consecutive patients with unilateral profound or total sensorineural deafness with the onset in early childhood, pure-tone audiometric examination and the measurement of p-ADH and plasma osmolality (p-OSM) were followed up once or twice a year as far as possible. At every testing, we performed careful history-taking about episodic vertigo/dizziness, fluctuant hearing loss, and tinnitus in order to find out whether patients had experienced these clinical signs of the development of DEH. RESULTS: Means and standard deviation (S.D.) of p-ADH level and osmolality in all samples tested (n=368) were 7.3+/-7.0pg/mL (0.7-52.0pg/mL), and 288.6+/-4.4mOsm/L (273-306mOsm/L), respectively. The mean of p-ADH level was much higher than those previously reported in children and adolescents. High levels of p-ADH (over 5.0pg/mL) were often observed in subjects between 6 and 19 years of age, but not so frequently in subjects of 20 years of age or older. Long-term follow-up of p-ADH levels revealed that DEH frequently developed in cases with persistent elevation of p-ADH. CONCLUSIONS: The elevation of p-ADH is likely to promote the development of DEH in cases of JUPD, although the underlying mechanism remains to be elucidated.