Monthly Archives: June 2009
Perception of Recorded Singing Voice Quality and Expertise: Cognitive Linguistics and Acoustic Approaches
The objective of the present pluridisciplinary study was to contribute to determine how a diversity of audience differently appreciates several versions resulting from different “restoration” treatments of one single original lyrical recording. We present here a joint analysis coupling psychological and linguistic analyses with acoustic descriptions on a unique research object: a Caruso’s piece of song diversely remastered on commercial CDs. Thirty-two subjects were selected contrasted on age (“younger than 30 years” and “older than 60 years”) related with their different experience of earlier technical recording devices (rendering through devices such as radio, 78 rpm records, CD…) and on expertise concerning musical acoustics (acousticians and/or musicians vs ordinary music lovers). Eleven excerpts of reediting of an opera record interpreted by Caruso were selected from what could found on the market. The listening protocol involved a free categorization task and the selection of excerpts on preference judgments. Each task involved subjects’ free commentaries about their choices as a joint output from psychological processing. A cluster analysis scaffold by a psycholinguistic processing of the verbal comments of the categories allowed to identify both commonalities and differences in groupings excerpts by the different groups of the subjects, along a diversity of criteria, varying according to age and expertise. Each excerpt can therefore be characterized both according to psychological and to acoustic criteria. This study has enabled us to develop the idea that a lyric voice is a multifaced object (cultural, esthetic, technical, physical), acoustic parameters being linked to the various sensory experiences and expertises of appraisers. Such pluridisciplinary research and the coupling of the correlated multiplicity of methodologies we developed acknowledge for a better understanding of listening practices and music-lover assessments here concerned with a specific musical style (opera), and a diversity of media technology (analogical or digital records, radio…) but that we expect to be generalized to a wide range of complex musical productions.
from the Journal of Voice
On the number of auditory filter outputs needed to understand speech: Further evidence for auditory channel independence1
The number of auditory filter outputs required to identify phonemes was estimated in two experiments. Stimuli were divided into 30 contiguous equivalent rectangular bandwidths (ERBN) spanning 80 to 7563 Hz. Normal-hearing listeners were presented with limited numbers of bands having frequency locations determined randomly from trial to trial to provide a general view, i.e., irrespective of specific band location, of the number of 1-ERBN-wide speech bands needed to identify phonemes. The first experiment demonstrated that 20 such bands are required to accurately identify vowels, and 16 are required to identify consonants. In the second experiment, speech-shaped noise or timereversed speech was introduced to the non-speech bands at various signal-to-noise ratios. Considerably elevated noise levels were necessary to substantially affect phoneme recognition, confirming a high degree of channel independence in the auditory system. The independence observed between auditory filter outputs supports current views of speech recognition in noise in which listeners extract and combine pieces of information randomly distributed both in time and frequency. These findings also suggest that the ability to partition incoming sounds into a large number of narrow bands, an ability often lost in cases of hearing impairment or cochlear implantation, is critical for speech recognition in noise.
from Hearing Research
Spatial hearing with a single cochlear implant in late-implanted adults
We assessed sound localisation abilities of late-implanted adults fitted with a single cochlear implant (CI) and examined whether these abilities are affected by the duration of implant use. Ten prelingually and four postlingually deafened adults who received a unilateral CI were tested in a sound-source identification task. Above chance performance was observed in those prelingual CI recipients who had worn their implant for longer time (9 years on average), revealing some monaural sound localization abilities in this population but only after extensive CI use. On the contrary, the four postlingual recipients performed equal or better with respect to the best prelingual participants despite shorter experience with the monaural implant (11 months on average). Our findings reveal that some sound localisation ability can emerge in prelingually deafened adults fitted with a single implant, at least in a controlled laboratory setting. This ability, however, appears to emerge only after several years of CI use. Furthermore, the results of four postlingually deafened adults suggest that early experience with auditory cues may result in more rapid acquisition of spatial hearing with a single CI.
from Hearing Research
ATP8B1 is essential for maintaining normal hearing
ATP8B1 deficiency is caused by autosomal recessive mutations in ATP8B1, which encodes the putative phospatidylserine flippase ATP8B1 (formerly called FIC1). ATP8B1 deficiency is primarily characterized by cholestasis, but extrahepatic symptoms are also found. Because patients sometimes report reduced hearing capability, we investigated the role of ATP8B1 in auditory function. Here we show that ATP8B1/Atp8b1 deficiency, both in patients and in Atp8b1G308V/G308V mutant mice, causes hearing loss, associated with progressive degeneration of cochlear hair cells. Atp8b1 is specifically localized in the stereocilia of these hair cells. This indicates that the mechanosensory function and integrity of the cochlear hair cells is critically dependent on ATP8B1 activity, possibly through maintaining lipid asymmetry in the cellular membranes of stereocilia.
Soft phonation index — a sensitive parameter?
Results The results of the study reveal that there was a statistically significant difference between the means of the SPI values between the control and the experimental groups.
Discussion It can be understood that SPI is a sensitive parameter to detect abnormalities in vocal fold approximation in the considered population of individuals with vocal nodules. This is in coherence with a study done on patients with vocal fold palsy and cordectomy, wherein SPI was found to be a good indicator of breathiness. The SPI mean obtained for participants in the control group was higher than the Western normative mean specified in MDVP, which highlights the importance of establishing normative values for Indian population.
Conclusion It can be concluded that SPI was sensitive to detect changes affecting vocal fold closure in unilateral vocal nodules. But this conclusion has to be generalized with caution keeping in mind that only one population with vocal pathology was studied. The factors of vocal fold physiology and mechanical properties of vocal tract, which may contribute to individual variations in SPI values, have to be considered for further research.
from the Indian Journal of Otolaryngology and Head and Neck Surgery
Speech Target Modulates Speaking Induced Suppression in Auditory Cortex
Results
The present MEG study investigated the effects of utterance rapidity and complexity on SIS: The greatest difference between speak and listen M100 amplitudes (i.e., most SIS) was found in the simple speech task. As the utterances became more rapid and complex, SIS was significantly reduced (p = 0.0003).
Conclusions
These findings are highly consistent with our model of how auditory feedback is processed during speaking, where incoming feedback is compared with an efference-copy derived prediction of expected feedback. Thus, the results provide further insights about how speech motor output is controlled, as well as the computational role of auditory cortex in transforming auditory feedback.
from BMC Neuroscience
A systematic review to determine the effectiveness of using amplification in conjunction with cochlear implantation
Method: RESEARCH DESIGN: A systematic review of the evidence that met the search criteria related to the use of amplification in adult implant users. All types of experiments were included with the exception of expert opinion. This systematic review ranked the levels of evidence related to these studies and distinguished the levels of evidence from judgments about the grade and strength of recommendations for the stated clinical question. STUDY SAMPLE: Fifty-two articles were initially reviewed with a final 11 articles meeting the search criteria and identified for in-depth analysis. DATA COLLECTION AND ANALYSIS: Several electronic databases and textbooks were searched to locate the evidence related to bimodal stimulation. Each article was reviewed using a check sheet and assigned a ranking for level of evidence (Levels 1-6) based on the type of research design that was used and a grade of evidence (A-D) based on the quality, relevance, and extensiveness of the study. Finally the level and grade were collapsed into only three categories to indicating the strength of the recommendations coming from each study and were classified as either strong (I), moderate (II), or weak (III).
Results: Several trends about bimodal stimulation were observed, which include (1) significantly better speech understanding in the bimodal condition for many participants; (2) in noise, the largest bimodal benefits in speech recognition; (3) variable findings on localization tasks; and (4) overall significant improvement in functional ability based on self-assessments. The preponderance of evidence received grades of B or C.
Antibiotics versus placebo or watchful waiting for acute otitis media: a meta-analysis of randomized controlled trials
Method: a meta-analysis of randomized controlled trials (RCTs) that were retrieved from searches performed in the PubMed and Cochrane databases, and compared antibiotic treatment with placebo or watchful waiting (delayed antibiotic treatment if clinically indicated) for patients with AOM.
Results: We identified seven trials comparing antibiotic treatment with placebo (all double-blinded) and four trials comparing antibiotic treatment with watchful waiting (two investigator-blinded and two open-label) trials, all of which involved children (6 months to 12 years). Clinical success was more likely with antibiotics than comparator treatment in: placebo-controlled trials [seven RCTs, 1405 patients, risk ratio (RR) = 1.11, 95% confidence interval (CI) = 1.05-1.18]; watchful waiting trials (four RCTs, 915 patients, RR = 1.18, 95% CI = 1.07-1.32); and all trials combined (11 RCTs, 2320 patients, RR = 1.13, 95% CI = 1.08-1.19). Similarly, persistence of symptoms 2-4 days after treatment initiation was less likely with antibiotics in: placebo-controlled trials (four RCTs, 1014 patients, RR = 0.75, 95% CI = 0.64-0.88) and all trials combined (five RCTs, 1299 patients, RR = 0.68, 95% CI = 0.54-0.85). Diarrhoea was more likely with antibiotics (seven RCTs, 1807 patients, RR = 1.50, 95% CI = 1.16-1.95). No differences between the compared treatments were found regarding other effectiveness and safety outcomes.
Nutritional factors in the pathogenesis of ear disease in children: a systematic review
Method: A systematic review was undertaken using Pubmed, SCOPUS, Cinahl on Ovid, the Cochrane Database and selected medical journals, with no language restriction. Nutritional mechanisms potentially related to ear disease and CSOM risks were reviewed. All studies (observational, case-control, cohort and clinical trials including randomised controlled trials) with nutrition-related information were included. The titles and/or abstracts of all retrieved studies were reviewed and full articles were obtained for relevant studies. Exclusion criteria were multiple publication or studies which did not report nutritional information.
Results: Supplementation studies using single micronutrients and vitamins to determine efficacy in reducing acute or chronic otitis media provided some evidence for an association of middle-ear pathology with deficiencies of zinc or vitamin A. Multi-micronutrient supplementation studies provided further support for a beneficial effect, although the number of studies was small and they were heterogeneous and uncontrolled. No human study was identified which specifically examined the association between copper, selenium or vitamin D status and middle-ear disease or infection.
Effectiveness of multi-channel unilateral cochlear implants for profoundly deaf children: a systematic review
Method: This examined 16 electronic data bases, plus bibliographies and references for published and unpublished studies. Abstracts were independently assessed against inclusion criteria by two researchers, results were compared and disagreements resolved. Included papers were then retrieved and further independently assessed in a similar way. Remaining studies had their data independently extracted by one of five reviewers and checked by another reviewer.
Results: From 1,580 abstracts and titles 15 studies were included. These were of moderate to poor quality. The large amount of heterogeneity in design and outcomes precluded meta-analysis. However, all studies reported that unilateral cochlear implants improved scores on all outcome measures. Additionally five economic evaluations found unilateral cochlear implants to be cost-effective for profoundly deaf children at UK implant centres.
From recording linguistic competence to supporting inferences about language acquisition in context
Student models for Intelligent Computer Assisted Language Learning (ICALL) have largely focused on the acquisition of grammatical structures. In this paper, we motivate a broader perspective of student models for ICALL that incorporates insights from current research on second language acquisition and language testing. We argue for a student model that includes a representation of the learner’s ability to use language in context and to perform tasks, as well as for an explicit activity model that provides information on the language tasks and the inferences for the student model they support. The student model architecture we present is being developed as part of the TAGARELA system, an intelligent workbook supporting the instruction of Portuguese.
The effectiveness of computer assisted pronunciation training for foreign language learning by children
This study investigates whether a computer assisted pronunciation training (CAPT) system can help young learners improve word-level pronunciation skills in English as a foreign language at a level comparable to that achieved through traditional teacher-led training. The pronunciation improvement of a group of learners of 11 years of age receiving teacher-fronted instruction was compared to that of a group receiving computer assisted pronunciation training by means of a system including an automatic speech recognition component. Results show that 1) pronunciation quality of isolated words improved significantly for both groups of subjects, and 2) both groups significantly improved in pronunciation quality of words that were considered particularly difficult to pronounce and that were likely to have been unknown to them prior to the training. Training with a computer-assisted pronunciation training system with a simple automatic speech recognition component can thus lead to short-term improvements in pronunciation that are comparable to those achieved by means of more traditional, teacher-led pronunciation training.
Evaluation of Inner Hair Cell and Nerve Fiber Loss as Sufficient Pathologies Underlying Auditory Neuropathy
Auditory neuropathy is a hearing disorder characterized by normal function of outer hair cells, evidenced by intact cochlear microphonic (CM) potentials and otoacoustic emissions (OAEs), with absent or severely dys-synchronized auditory brainstem responses (ABRs). To determine if selective lesions of inner hair cells (IHCs) and auditory nerve fibers (ANFs) can account for these primary clinical features of auditory neuropathy, we measured physiological responses from chinchillas with large lesions of ANFs (about 85%) and IHCs (45% loss in the apical half of the cochlea; 73% in the basal half). Distortion product OAEs and CM potentials were significantly enhanced, whereas summating potentials and compound action potentials (CAPs) were significantly reduced. CAP threshold was elevated by 7.5 dB, but response synchrony was well preserved down to threshold levels of stimulation. Similarly, ABR threshold was elevated by 5.6 dB, but all waves were present and well synchronized down to threshold levels in all animals. Thus, large lesions of IHCs and ANFs reduced response amplitudes but did not abolish or severely dys-synchronize CAPs or ABRs. Pathologies other than or in addition to ANF and IHC loss are likely to account for the evoked potential dys-synchrony that is a clinical hallmark of auditory neuropathy in humans.
from Hearing Research
Sex hormones and hearing: A pioneering area of enquiry
Our last contribution comes from a researcher with a long history of investigating behavioral and neural aspects of age-related hearing loss in mouse models. In this special issue, Willott (2009) summarizes the interactions that aging, special acoustic environments and hormonal changes can have on hearing, with special emphasis on male/female differences and central auditory plasticity in the C57BL/6J mouse strain. In a series of coordinated experiments, Willott and colleagues have uncovered some sex differences in hearing sensitivities and responses to augmented acoustic environments that generally delay the onset and progression of rapid, age-linked hearing loss in inbred mouse strains that have one or more copies of the ahl gene. For instance, changes in neuron numbers at the level of the cochlear nucleus were discovered.
In closing, this special edition of Hearing Research provides a unique exposition where the main findings in a youthful but burgeoning subfield of hearing science and auditory neuroscience are put forth in one issue. Each contribution provides key references for the topic, rather than listing exhaustive bibliographies, giving the reader an opportunity to rapidly obtain most of the essence of what is known about how sex hormones can influence how and what we hear.
from Human Brain Mapping
