Monthly Archives: January 2009
Hearing preservation and intraoperative auditory brainstem response and cochlear nerve compound action potential monitoring in the removal of small acoustic neurinoma via the retrosigmoid approach
Objective: Hearing preservation is the main focus of small acoustic neurinoma (AN) removal. Refinement of intraoperative auditory monitoring may improve postoperative hearing. We have introduced a newly designed intracranial electrode enabling continuous monitoring of the cochlear nerve compound action potential (CNAP). We performed simultaneous monitoring of the auditory brainstem response (ABR) and CNAP during retrosigmoid small AN removal, and clarified the surgical outcome and the usefulness of CNAP monitoring.
Methods: Twenty-two consecutive patients with a small AN underwent retrosigmoid tumour removal with attempting hearing preservation. ABR and CNAP were simultaneously monitored during tumour removal.
Results: AN was totally removed in all patients without facial palsy. Preservation rate of useful and serviceable hearing was 82% and 91%, respectively. During microsurgical tumour removal, various surgical equipments and procedures intensified artefacts of ABR, and reliable ABR monitoring with distinct wave V was obtained in 9/22 patients. Unaffected by artefacts, reliable CNAP monitoring was obtained more frequently (in 20/22 patients) than ABR (p = 0.0005). CNAP on completion of tumour removal predicted hearing preservation with no false positive or negative (100% sensitivity and 100% specificity). CNAP changed dynamically and stepwise with surgical manipulations.
Conclusion: The retrosigmoid approach using auditory monitoring for a small AN can accomplish total tumour removal with an excellent hearing preservation rate. CNAP provides reliable auditory monitoring more frequently than ABR, reflects the intraoperative auditory function almost in real-time, predicts postoperative hearing with excellent sensitivity and specificity, and is more useful for monitoring in the removal of small AN with hearing preservation.
The spectrum of Susac’s syndrome
Abstract We report a series of four patients with Susac’s syndrome, which is characterized by the triad of visual loss due to branch retinal artery occlusions, sensorineural hearing loss due to cochlear involvement, and encephalopathy due to cerebral microangiopathy. However, as we describe in this series, the clinical triad may not be apparent for years, resulting in delays in diagnosis. We also report the variable cerebrospinal fluid and brain magnetic resonance imaging findings, and treatment using a combination of steroids and intravenous immunoglobulin, followed by mycophenolate mofetil.
Acquisition of singular-plural morphology.
A manual search paradigm explored the development of English singular-plural comprehension. After being shown a box into which they could reach but not see, infants heard verbal descriptions about the contents of the box (e.g., “There are some cars in the box” vs. “There is a car in the box)” and were then allowed to reach into the box. At 24 months of age, but not at 20 months, infants’ search patterns were influenced by verbal number markings. However, verbal number marking did not influence search behavior when plurality was signaled by noun morphology alone. These data converge with parental reports and preferential looking studies concerning the developmental course of mastery of English plural marking and show that infants can create a mental model of the number of objects on the basis of singular-plural morphology alone. (PsycINFO Database Record (c) 2009 APA, all rights reserved)
Gene × environment interactions in reading disability and attention-deficit/hyperactivity disorder.
This article examines Gene × Environment (G × E) interactions in two comorbid developmental disorders–reading disability (RD) and attention-deficit/hyperactivity disorder (ADHD)–as a window on broader issues on G × E interactions in developmental psychology. The authors first briefly review types of G × E interactions, methods for detecting them, and challenges researchers confront in interpreting such interactions. They then review previous evidence for G × E interactions in RD and ADHD, the directions of which are opposite to each other: bioecological for RD and diathesis stress for ADHD. Given these results, the authors formulate and test predictions about G × E interactions that would be expected at the favorable end of each symptom dimension (e.g., above-average reading or attention). Consistent with their prediction, the authors found initial evidence for a resilience interaction for above-average reading: higher heritability in the presence of lower parental education. However, they did not find a G × E interaction at the favorable end of the ADHD symptom dimension. The authors conclude with implications for future research. (PsycINFO Database Record (c) 2009 APA, all rights reserved)
Perception of vowel length by Japanese- and English-learning infants.
This study investigated vowel length discrimination in infants from 2 language backgrounds, Japanese and English, in which vowel length is either phonemic or nonphonemic. Experiment 1 revealed that English 18-month-olds discriminate short and long vowels although vowel length is not phonemically contrastive in English. Experiments 2 and 3 revealed that Japanese 18-month-olds also discriminate the pairs but in an asymmetric manner: They detected only the change from long to short vowel, but not the change in the opposite direction, although English infants in Experiment 1 detected the change in both directions. Experiment 4 tested Japanese 10-month-olds and revealed a symmetric pattern of discrimination similar to that of English 18-month-olds. Experiment 5 revealed that native adult Japanese speakers, unlike Japanese 18-month-old infants who are presumably still developing phonological perception, ultimately acquire a symmetrical discrimination pattern for the vowel contrasts. Taken together, our findings suggest that English 18-month-olds and Japanese 10-month-olds perceive vowel length using simple acoustic?phonetic cues, whereas Japanese 18-month-olds perceive it under the influence of the emerging native phonology, which leads to a transient asymmetric pattern in perception. (PsycINFO Database Record (c) 2009 APA, all rights reserved)
Studies of adults can inform accounts of theory of mind development.
There is strong evidence that developments in children’s theory of mind (ToM) at 3?4 years are related to developments in language and executive function. However, these relationships might exist for 2 reasons. First, language and executive function might be necessary for the mature ToM abilities that children are in the process of developing. Second, language and executive function may be necessary for developing ToM but have no necessary role in mature ToM. It is difficult to distinguish between these possibilities if researchers only study young children. Studies of adults can provide direct evidence about the role of language and executive function in mature ToM. Recent work suggests that impaired executive function has multiple roles in adult ToM but that severely impaired grammar can leave ToM structurally intact. While studies of children report that ToM correlates with both language and executive function, findings from adults suggest that these relationships should be interpreted in importantly different ways. (PsycINFO Database Record (c) 2009 APA, all rights reserved)
Synesthesia: A new approach to understanding the development of perception.
In this article, the authors introduce a new theoretical framework for understanding intersensory development. Their approach is based upon insights gained from adults who experience synesthesia, in whom sensory stimuli induce extra cross-modal or intramodal percepts. Synesthesia appears to represent one way that typical developmental mechanisms can play out by magnifying connections present in early life that are pruned and/or inhibited during development but persist in muted form in all adults. As such, the study of synesthesia provides valuable insights into the nature of intersensory development. The authors review evidence on the perceptual reality and neural basis of synesthesia, then summarize developmental models and evidence that its underlying mechanisms are universal in adults. They illustrate how evidence for consistent sensory associations in adults leads to predictions about toddlers’ perception and present 3 bodies of work that have confirmed those hypotheses. They end by describing novel hypotheses about intersensory development that arise from this framework. Such intersensory associations appear to reflect intrinsic sensory cortical organization that influences the development of perception and of language and that may constrain the learning of environmentally based associations. (PsycINFO Database Record (c) 2009 APA, all rights reserved)
Aerodynamics of the Pseudo-Glottis
Objective: The aim of this work is to study the hitherto unclear aerodynamic parameters of the pseudo-glottis following total laryngectomy. These parameters include airflow rate, sub-pseudo-glottic pressure (SubPsG), efficiency and resistance, as well as sound pressure level (SPL). Patients and Methods: Eighteen male patients who have undergone total laryngectomy, with an age range from 54 to 72 years, were investigated in this study. All tested patients were fluent esophageal ‘voice’ speakers utilizing tracheo-esophageal prosthesis. The airflow rate, SubPsG and SPL were measured. Results: The results showed that the mean value of the airflow rate was 53 ml/s, the SubPsG pressure was 13 cm H2O, while the SPL was 66 dB. The normative data obtained from the true glottis in healthy age-matched subjects are 89 ml/s, 7.9 cm H2O and 70 dB, respectively. Other aerodynamic indices were calculated and compared to the data obtained from the true glottis. Conclusion: Such a comparison of the pseudo-glottic aerodynamic data to the data of the true glottis gives an insight into the mechanism of action of the pseudo-glottis. The data obtained suggests possible clinical applications in pseudo-voice training.
Socioeconomic status and the developing brain
Childhood socioeconomic status (SES) is associated with cognitive achievement throughout life. How does SES relate to brain development, and what are the mechanisms by which SES might exert its influence? We review studies in which behavioral, electrophysiological and neuroimaging methods have been used to characterize SES disparities in neurocognitive function. These studies indicate that SES is an important predictor of neurocognitive performance, particularly of language and executive function, and that SES differences are found in neural processing even when performance levels are equal. Implications for basic cognitive neuroscience and for understanding and ameliorating the problems related to childhood poverty are discussed.
Functional Outcomes and Reevaluation of Esophageal Speech After Free Jejunal Transfer in Two Hundred Thirty-Six Cases
Swallowing and communication are occasionally impaired after free jejunal transfer. Here, the relationship between surgical procedure and functional outcome was analyzed in 236 patients undergoing free jejunal transfer after total laryngopharyngectomy from 1992 through 2003. Swallowing and communication functions were also investigated with a questionnaire in 40 long-surviving patients. Although oral feeding could be resumed after surgery in most patients, anastomotic stricture and nasal regurgitation occurred in 12.7% and 29.7% of patients, respectively. Use of our standardized procedure, the tensed jejunal method, significantly reduced the incidence of stricture (P < 0.01) but increased the rate of nasal regurgitation; however, in most cases regurgitation gradually resolved. Of the 40 long-surviving patients, 17 attended a speech rehabilitation program at which 12 learned to perform esophageal speech without voice restoration procedures (11 of the 12 had received a tensed jejunal graft). Our standardized procedure helps prevent strictures and encourages esophageal speech.
from the Annals of Plastic Surgery
Symptoms of detachment from the self or from the environment in patients with an acquired deficiency of the special senses
To compare the frequency of symptoms of detachment from the self or from the environment (DD) in patients with an acquired deficiency of the special senses, a questionnaire for DD symptoms [12] and the GHQ12 questionnaire for common mental disorders [16] were auto-administered to patients with hearing-loss (N = 40), peripheral vestibular disease (N = 40) or bilateral retinal disease (N = 40), and to 80 healthy subjects. Patients with retinal disease and patients with vestibular disease reported DD symptoms more frequently & severe than patients with hearing loss and healthy subjects. DD scores were related to the GHQ12 scores and to the type of sensory dysfunction. DD symptoms are more frequent & severe in patients with an acquired deficiency of the special senses, associated to symptoms of common mental disorders.
from Vestibular Research
Time course of the change in subjective straight-ahead after vestibular stimulation
We measured the change in subjective straight-ahead (SSA) as a function of time after vestibular stimulation. Blindfolded subjects were exposed to sudden stops after constant velocity (72°/s) z-axis rotation. They were then asked to open their eyes and continuously adjust the position of a laser spot to the position perceived as straight ahead (visual localization of SSA) immediately, or after a 10 s or 20 s delay following the sudden stop. The deviation of SSA increased to 20 s in the opposite direction of acceleration and then decreased gradually when the visual localization task was started immediately after sudden stops. The time courses changed systematically when the task was started after a delay of 10 s or 20 s following sudden stops: the initial increase component and maximum magnitude of the SSA deviation fell off with delay length, but the increase-decrease pattern was preserved. These delay effects on the time course of the SSA deviation might reflect that the velocity-to-orientation/position integrator for perception of body orientation in vestibular system might be inactivated temporarily during the delay period after vestibular stimulation without visual input.
from Vestibular Research
Vestibulo-ocular (oVEMP) responses produced by bone-conducted sound stimuli applied to the mid-sagittal plane of the head
Recently several studies have yielded evidence that impulses of bone-conducted (BC) sound can produce short-latency myogenic responses in the extraocular muscles, which are probably mediated by otolithic afferents. These responses, although miniscule, can be recorded with surface electrodes and are termed ocular vestibular evoked myogenic potentials (oVEMP). It is assumed that in response to low-frequency BC-sound stimuli the head moves predominantly along the axis from the site of the applied stimulus to the opposite side. Thus, oppositely-directed accelerations along a particular axis would produce oppositely-directed compensatory vestibulo-ocular responses (VOR) and oVEMPs. The aim of this study was to investigate whether the oVEMPs would reflect these direction-dependent VOR responses. Single cycles of 125 and 250 Hz BC tones were applied to opposite sides of two approximately orthogonal, naso-occipital (x) and vertical (z) axes of the head. oVEMP responses were recorded with standard bilateral vertical EOG montages. The responses in all twelve healthy subjects showed consistent differences with regard to the latency and/or shape of the response to stimuli applied to opposite sides of the head. These differences likely reflect different patterns of electro-myographic activity of the extraocular muscles, which may be mediated by groups of vestibular (probably otolithic) afferents with differently-orientated spatial polarization vectors.
from Vestibular Research
Comparing auditory perception and speech production outcomes: Non-language specific assessment of auditory perception and speech production in children with cochlear implants
Language-independent assessment tools evaluate the progress of children who receive a cochlear implant, allowing large pooling of data for better access to insurers and other health care professionals. One hundred and seventeen children from centres in the United Kingdom, Iran and Turkey were assessed on two measures over a five-year test interval. There is a significant improvement over time for the Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) measures. There was a significant difference between scores for different language groups: accounted for by the differences in age at implantation. There was a significant effect of age at implantation up to three years of device use. There were high correlations between the CAP and SIR scores. A longer duration of deafness resulted in a higher score for both scales; however, there was no relationship when correlated for age. Finally, the CAP pre-operative score allows us to predict the post-operative SIR scores. The scales are validated; reliable measures which can be used across countries and languages. This allows greater ability to pool data allowing data to be generalised across population groups, providing more power to prove that cochlear implantation is a viable treatment for children with bilateral severe-to-profound hearing loss. Copyright © 2009 John Wiley & Sons, Ltd.
HiRes with Fidelity 120 benefit in native speakers of Korean
In HiRes 120 sound processing, the spectral bands are created by precisely varying the proportion of current delivered simultaneously to adjacent electrodes through active current steering. The purpose of this study was to examine performance of native Korean speakers with HiRes 120. Eleven adults with postlinguial hearing loss participated in the study. The difference between baseline and three-month HiRes 120 performance was significant for all tests (p < 0.05). For monosyllabic words, eight subjects obtained higher scores with HiRes 120. For the Hearing in Noise Test (HINT), ten subjects obtained higher scores with standard HiRes. These results show Korean speakers exhibit improved speech understanding in quiet and in noise with HiRes 120. All subjects preferred the new HiRes 120 sound processing option. Copyright © 2009 John Wiley & Sons, Ltd.
