Auditory Research Research Articles

In Search of Pronunciation Peculiarities Characteristic to Vilnians: Vowel Shortening Tendencies of Vilnians Aged 25–35

The article discusses the question of Vilnius variant exclusivity and covers one fragment of Vilnius as a complex microcosm: exclusivity of Vilnius variant is examined by analysing spontaneous speech among Vilnians aged 25–35. Empirical research units are variants of phonological variables /i·/ and /u·/ in unstressed positions. Applying two different research methods – one based on hearing (auditory) and an instrumental one – the parameter of duration of these long vowels was evaluated in the spontaneous speech of the interviewed Vilnians aged 25-35. The results of the auditory research and instrumental examination (instrumental checks of almost 800 variants of phonological variables /i·/ and /u·/ in unstressed positions and 384 variants in stressed positions have been carried out) demonstrate that shortened variants of variables /i·/ and /u·/ in unstressed positions are characteristic of the language of the research group. Unstressed variants of the variables under investigation cover the duration continuum range between 60 and 80 milliseconds. Duration range of the variants of variables /i·/ and /u·/ in stressed positions starts at approx. 90 ms. Duration data of variants /i·/ and /u·/ in stressed and unstressed positions was correlated and this correlation reveals that duration areas of these variants almost overlap. Transitional zone is between ~80 and 90 ms. Quantitative reduction is very apparent so it is possible to make an assumption that this tendency reflects this particular peculiarity of the language specific to Vilnians. However, it is essential to state that even after shortened variants of variables /i·/ and /u·/ in unstressed positions are present in the speech of people belonging to different generations or having different sociolinguistic portraits, this characteristic cannot be considered as a distinctive characterization of Vilnius language (Vilnius variant). Distinguishing features in variability analysis cannot be at the same time primary, i. e. distinctive, as well as tertiary, i. e. denoting, characteristic. In this research this would be the case. The value of tertiary features is characteristic of quantitative (shortened) variants of variables /i·/ and /u·/ in some dialects. Therefore, methodologically it is not accurate to evaluate vowel shortening tendency of Vilnians as distinctive characteristics specific to the people of Vilnius. These features are characteristic, but they do not have a clear single-plan dividing power.

Auditory Training: Consideration of Peripheral, Central-Auditory, and Cognitive Processes.

It has been 8 years since Seminars in Hearing published an issue devoted to auditory training (2007, issue no. 2). Much has happened in the research literature during this time. In 2005, Sweetow and Palmer wrote the first systematic review investigating the efficacy of auditory training in adults.1 The review included six studies with varying levels of evidence. Three were randomized controlled trials, two were nonrandomized controlled trials, and one used a repeated-measures design. Only one study assessed participants both immediately posttraining and at a later follow-up evaluation. Additionally, all of the studies used one-on-one in-person auditory training. This important review highlighted the need for high-quality auditory training research demonstrating efficacy, effectiveness, and efficiency

Physics underlying the physiology of the ear.

Physics underlying the physiology of the ear.

Israel Society for Auditory Research (ISAR) 2015 Annual Scientific Conference

Israel Society for Auditory Research (ISAR) 2015 Annual Scientific Conference

The Accent Differences of Some Word Endings in the Prienai Subdialect: Instrumental and Auditory Research

Atsižvelgiant į tai, kad empirinė medžiaga ir eksperimentiniai aukštaičių šnektų tyrimai rodo nevienodai tariant kai kurias skirtingos kilmės dvibalsinių galūnių priegaides, norėta nustatyti, ar rytinių vakarų aukštaičių kauniškių Prienų šnektoje taip pat yra skiriamos tokios fonemiškai vienodos formos kaip sakαĭ. ~ sakaĭ (daiktav. dgs. vard.) : sakaĭ. ~ sakaĭ (veiksmaž. es. l. 2 a.), laikαĭ. ~ laikaĭ (daiktav. dgs. vard.) : laikaĭ. ~ laikaĭ (veiksmaž. es. l. 2 a.), vilkαĭ. ~ vilkaĭ (daiktav. dgs. vard.) : vilkaĭ. ~ vilkaĭ (veiksmaž. būt. k. l. 2 a.) ir pan. Atliktas instrumentinis ir identifikacinis audicinis skirtingos (cirkumfleksinės vs. akūtinės) kilmės galūnių dvibalsių tyrimas parodė, kad Prienų šnektoje tirtosios formos išties nėra visiškai sutapusios: lyginamųjų daiktavardžių ir veiksmažodžių dvibalsinių galūnių priegaidžių skirtumus rodo ir akustiniai požymiai, ir empiriniai bei statistiniai garsinio suvokimo vertinimo rezultatai.

Cochleotopy of human cochlear nucleus

IntroductionThe human peripheral auditory pathway in infants is a relatively less explored domain in auditory research. In the present study, the cochlea, auditory nerve (AN) and the cochlear nucleus (CN) were examined using immunohistochemistry and light and electron-microscopy. MethodsThe study was performed on specimens retrieved from a 40-day-old infant who could not survive after corrective surgery for congenital cyanotic heart disease. The donation was done in accordance with the protocol approved by the Human Ethics Committee, All India Institute of Medical Sciences (AIIMS), New Delhi, India. ResultsThe AN revealed degeneration of nerve fascicles originating from the spiral ganglion neurons of the middle and basal turns of the cochlea. The proximal and middle segments of the nerve showed varying degrees of degenerating fibers with macrophages whereas the most distal part of the nerve showed dilated endoneurial capillaries without any degeneration. On electron-microscopy, the nerve revealed features of acute myelinopathy. The differential perisomatic synaptophysin immunoreactivity was observed in the CN. The unaffected neurons showed strong microtubule-associated protein 2 (MAP-2) immunoreactivity, while those denervated revealed decreased staining. The VCN showed varying degree of parvalbumin (PV) and calbindin (CB) immunostaining with AN fibers and terminals showing strong immunoreactivity for PV. The AN revealed strong immunoreactivity for CB on the affected side. The spiral ganglion neurons did not reveal any pathological changes. DiscussionThe results provide a cochleotopic map of the human CN that maybe relevant in better understanding of the tonotopic organization and will be helpful during auditory implants in children.

Aminoglycoside ototoxicity and hair cell ablation in the adult gerbil: A simple model to study hair cell loss and regeneration

The Mongolian gerbil, Meriones unguiculatus, has been widely employed as a model for studies of the inner ear. In spite of its established use for auditory research, no robust protocols to induce ototoxic hair cell damage have been developed for this species. In this paper, we demonstrate the development of an aminoglycoside-induced model of hair cell loss, using kanamycin potentiated by the loop diuretic furosemide. Interestingly, we show that the gerbil is relatively insensitive to gentamicin compared to kanamycin, and that bumetanide is ineffective in potentiating the ototoxicity of the drug.We also examine the pathology of the spiral ganglion after chronic, long-term hair cell damage. Remarkably, there is little or no neuronal loss following the ototoxic insult, even at 8 months post-damage. This is similar to the situation often seen in the human, where functioning neurons can persist even decades after hair cell loss, contrasting with the rapid, secondary degeneration found in rats, mice and other small mammals. We propose that the combination of these factors makes the gerbil a good model for ototoxic damage by induced hair cell loss.

Meaning in the avian auditory cortex: neural representation of communication calls.

Understanding how the brain extracts the behavioral meaning carried by specific vocalization types that can be emitted by various vocalizers and in different conditions is a central question in auditory research. This semantic categorization is a fundamental process required for acoustic communication, and presupposes discriminative and invariance properties of the auditory system for conspecific vocalizations. Songbirds have been used extensively to study vocal learning, but the communicative function of all their vocalizations and their neural representation has yet to be examined. In this study, we first generated a library containing almost the entire zebra finch vocal repertoire, and organised communication calls along nine different categories according to their behavioral meaning. We then investigated the neural representations of these semantic categories in the primary and secondary auditory areas of six anesthetised zebra finches. To analyse how single units encode these call categories, we described neural responses in terms of their discrimination, selectivity and invariance properties. Quantitative measures for these neural properties were obtained with an optimal decoder using both spike counts and spike patterns. Information theoretic metrics show that almost half of the single units encode semantic information. Neurons achieve higher discrimination of these semantic categories by being more selective and more invariant. These results demonstrate that computations necessary for semantic categorization of meaningful vocalizations are already present in the auditory cortex, and emphasise the value of a neuro-ethological approach to understand vocal communication.

Formative evaluation of a multimedia self-administered computerized hearing loss prevention program

Objective: To determine which features make a computer-based hearing health education intervention effective, easy to use, and enjoyable. The study examined which features of a multimedia self-administered computerized hearing loss prevention program, developed by the National Center for Rehabilitative Auditory Research (referred to as the NCRAR-HLPP), users liked and disliked, and the reasons why. Design: A formative evaluation was conducted in which participants completed a questionnaire to assess knowledge and attitudes towards hearing and hearing loss prevention, used the NCRAR-HLPP, completed the questionnaire for a second time, and were interviewed to learn their opinions about the NCRAR-HLPP. Study sample: Twenty-five male and four female Veterans recruited from the Portland VA Medical Center who were aged between 25 and 65 years. Results: Participants reported that using the NCRAR-HLPP was a positive experience. Ease of use, multimedia content, personal relevance, and use of emotion were positive features of the program. The questionnaire showed increased knowledge and improved attitude scores following use of the program. Conclusion: This formative evaluation showed changes designed to target user preferences and improve user instructions will be made in future versions of the program.

A Bayesian perspective on tinnitus pitch matching.

New tinnitus therapies are being developed and marketed that target the patient's tinnitus frequency. This frequency is estimated clinically by pitch matching, which has the patient identify the pure tone that is closest to the perceived tinnitus frequency. Though widely used, pitch matching is heavily criticized as unreliable, and the degree of reliability varies among patients. At the very least, it is recommended that multiple pitch matches be used to identify the patient's tinnitus frequency. Even so, it is not clear how many pitch matches to collect, how they should be combined, or how doing so will enhance the audiologist's certainty about the true tinnitus frequency. In this article, we describe a simple Bayesian method of sequentially combining pitch matches until acceptable precision is achieved and illustrate the method in 10 patients with chronic tinnitus. Subjects were recruited from previous study participants and support group attendees at the National Center for Rehabilitative Auditory Research. Thirty tinnitus pitch matches were elicited from 10 patients with chronic, monotonal tinnitus. A Bayesian sequential analysis yielded estimated tinnitus frequencies for 7 patients that were within one-quarter octave of their true value with 90% certainty. Between four and twenty pitch matches were required to achieve acceptable results in these seven patients. Despite criticism, pitch matching is widely used to estimate tinnitus frequency. We address reliability concerns with a Bayesian sequential analysis to jointly estimate tinnitus frequency and reliability. The method is easily applied.

Zebrafish in auditory research: are fish better than mice?

Sensory inner and outer hair cells (IHCs and OHCs) in the mammalian organ of Corti mediate the perception of sound, and hair cells (HCs) in the vestibular system detect head movements. Their characteristic feature is the ‘hair bundle’ of actin-based stereocilia that are arranged in three rows, with increasing length toward the apical cell pole. Sound- or movement-induced deflection towards the longest row opens mechanoelectrical transduction (MET) channels, whereas movement in the opposite direction closes these ion channels. Accordingly, opening and closing of the MET channels transduce sound information and movement of the head into receptor potentials in auditory and vestibular hair cells, respectively. Depolarization induces calcium-dependent neurotransmitter release from specialized presynaptic structures in IHCs and vestibular HCs; the resultant EPSP modulates action potential firing in afferent nerves. In OHCs, receptor potentials produce somatic length changes that comprise the cochlear amplifier and underlie the high sensitivity and frequency selectivity of mammals. The response of the HC membrane potential to MET channel activation is tuned and characterized by a distinct profile of K+ channels in the basolateral membrane (Schwander et al. 2010).

Disparities in auditory physiology and pathology between C57BL/6J and C57BL/6N substrains

C57BL/6 inbred mice are frequently used as models in auditory research, mostly the C57BL/6J and C57BL/6N substrains. Genetic variation and phenotypic disparities between these two substrains have been extensively investigated, but conflicting information exists about differences in their auditory and vestibular phenotypes. Literature-based comparisons are rendered difficult or impossible because most auditory publications do not designate the substrain used. We therefore evaluated commercial C57BL/6N and C57BL/6J mice for their baseline auditory brainstem response (ABR) thresholds at 3 months of age as well as their susceptibility to noise exposure and aminoglycoside antibiotics. Both substrains have similar thresholds at 4 and 12 kHz, but C57BL/6N show significantly higher baseline thresholds at 24 and 32 kHz. Because of these elevated thresholds, the N substrain is unsuitable as a model for drug ototoxicity, which primarily affects high frequencies. Exposure to 2–20 kHz broadband noise for 2 h at 110 dB produced significantly higher threshold shifts in the J substrain. These results suggest caution in the selection of C57BL/6 substrains for auditory research and indicate the need to specify substrains, age and the breeding source in all publications.

Menu Navigation With In-Vehicle Technologies: Auditory Menu Cues Improve Dual Task Performance, Preference, and Workload

Auditory display research for driving has mainly examined a limited range of tasks (e.g., collision warnings, cell phone tasks). In contrast, the goal of this project was to evaluate the effectiveness of enhanced auditory menu cues in a simulated driving context. The advanced auditory cues of “spearcons” (compressed speech cues) and “spindex” (a speech-based index cue) were predicted to improve both menu navigation and driving. Two experiments used a dual task paradigm in which users selected songs on the vehicle’s infotainment system. In Experiment 1, 24 undergraduates played a simple, perceptual-motor ball-catching game (the primary task; a surrogate for driving), and navigated through an alphabetized list of 150 song titles—rendered as an auditory menu—as a secondary task. The menu was presented either in the typical visual-only manner, or enhanced with text-to-speech (TTS), or TTS plus one of three types of additional auditory cues. In Experiment 2, 34 undergraduates conducted the same secondary task while driving in a simulator. In both experiments, performance on both the primary task (success rate of the game or driving performance) and the secondary task (menu search time) was better with the auditory menus than with no sound. Perceived workload scores as well as user preferences favored the enhanced auditory cue types. These results show that adding audio, and enhanced auditory cues in particular, can allow a driver to operate the menus of in-vehicle technologies more efficiently while driving more safely. Results are discussed with multiple resources theory.

Did you hear that? The role of stimulus similarity and uncertainty in auditory change deafness

Change deafness, the auditory analog to change blindness, occurs when salient, and behaviorally relevant changes to sound sources are missed. Missing significant changes in the environment can have serious consequences, however, this effect, has remained little more than a lab phenomenon and a party trick. It is only recently that researchers have begun to explore the nature of these profound errors in change perception. Despite a wealth of examples of the change blindness phenomenon, work on change deafness remains fairly limited. The purpose of the current paper is to review the state of the literature on change deafness and propose an explanation of change deafness that relies on factors related to stimulus information rather than attentional or memory limits. To achieve this, work on across several auditory research domains, including environmental sound classification, informational masking, and change deafness are synthesized to present a unified perspective on the perception of change errors in complex, dynamic sound environments. We hope to extend previous research by describing how it may be possible to predict specific patters of change perception errors based on varying degrees of similarity in stimulus features and uncertainty about which stimuli and features are important for a given perceptual decision.

Probing auditory scene analysis.

Probing auditory scene analysis.

Transcriptionist saturation: knowing too much about sensitive health and social data

The paper describes and interprets the experiences of transcriptionists employed to translate recorded auditory research, medical, court data into text and specifically when the research is sensitive and the audio source material may be traumatic to hear. This study highlights the ongoing need for transcriptionists to be recognized in the ethics process as a potentially vulnerable group who need greater support and debriefing when transcribing sensitive health and social data. Qualitative research. Telephone interviews were conducted with 12 transcriptionists in Australia and New Zealand during 2012, who had transcribed sensitive material and reported issues with transcribing certain topics. Accuracy and confidentiality were paramount in this work. Seven participants reported negative emotional and physical effects from transcribing sensitive material On the other hand six participants found the work enjoyable. The majority of the transcriptionists did not receive any debriefing after transcribing sensitive material. The participants developed their own strategies to deal with the effects of transcribing sensitive materials such as online support groups, relaxation activities and unofficial debriefing with friends and family.

Israel Society for Auditory Research (ISAR) 2014 Annual Scientific Conference

Article Israel Society for Auditory Research (ISAR) 2014 Annual Scientific Conference was published on September 1, 2014 in the journal Journal of Basic and Clinical Physiology and Pharmacology (volume 25, issue 3).

Behavioral responses of deafened guinea pigs to intracochlear electrical stimulation: a new rapid psychophysical procedure

In auditory research the guinea pig is often preferred above rats and mice because of the easily accessible cochlea and because the frequency range of its hearing is more comparable to that of humans. Studies of the guinea-pig auditory system primarily apply histological and electrophysiological measures. Behavioral animal paradigms, in particular in combination with these histological and electrophysiological methods, are necessary in the development of new therapeutic interventions. However, the guinea pig is not considered an attractive animal for behavioral experiments. Therefore, the purpose of this study was to develop a behavioral task suitable for guinea pigs, that can be utilized in cochlear-implant related research. Guinea pigs were trained in a modified shuttle-box in which a stream of air was used as unconditioned stimulus (UCS). A stream of air was preferred over conventionally used methods as electric foot-shocks since it produces less stress, which is a confounding factor in behavioral experiments. Hearing guinea pigs were trained to respond to acoustic stimuli. They responded correctly within only five sessions of ten minutes. The animals maintained their performance four weeks after the right cochlea was implanted with an electrode array. After systemic deafening, the animals responded in the first session immediately to intracochlear electrical stimulation. These responses were not affected by daily chronic electrical stimulation (CES). In conclusion, the present study demonstrates that guinea pigs can be trained relatively fast to respond to acoustic stimuli, and that the training has a lasting effect, which generalizes to intracochlear electrical stimulation after deafening. Furthermore, it demonstrates that bilaterally deafened guinea pigs with substantial (∼50%) loss of spiral ganglion cells (SGCs), detect intracochlear electrical stimulation.

Anatomy of the auditory thalamocortical system in the mongolian gerbil: Nuclear origins and cortical field‐, layer‐, and frequency‐specificities

Knowledge of the anatomical organization of the auditory thalamocortical (TC) system is fundamental for the understanding of auditory information processing in the brain. In the Mongolian gerbil (Meriones unguiculatus), a valuable model species in auditory research, the detailed anatomy of this system has not yet been worked out in detail. Here, we investigated the projections from the three subnuclei of the medial geniculate body (MGB), namely, its ventral (MGv), dorsal (MGd), and medial (MGm) divisions, as well as from several of their subdivisions (MGv: pars lateralis [LV], pars ovoidea [OV], rostral pole [RP]; MGd: deep dorsal nucleus [DD]), to the auditory cortex (AC) by stereotaxic pressure injections and electrophysiologically guided iontophoretic injections of the anterograde tract tracer biocytin. Our data reveal highly specific features of the TC connections regarding their nuclear origin in the subdivisions of the MGB and their termination patterns in the auditory cortical fields and layers. In addition to tonotopically organized projections, primarily of the LV, OV, and DD to the AC, a large number of axons diverge across the tonotopic gradient. These originate mainly from the RP, MGd (proper), and MGm. In particular, neurons of the MGm project in a columnar fashion to several auditory fields, forming small- and medium-sized boutons, and also hitherto unknown giant terminals. The distinctive layer-specific distribution of axonal endings within the AC indicates that each of the TC connectivity systems has a specific function in auditory cortical processing.

The unknown effects of amplitude envelope: A survey of Hearing Research

In auditory research, the use of amplitude-steady tones with abrupt onsets and offsets is quite common. While these types of “flat” tones offer a great deal of control, they are not representative of the types of sounds we hear outside the laboratory. In everyday listening we are much more likely to encounter “percussive” (i.e., exponentially decaying) sounds, with offsets conveying detailed information such as the materials and force used to produce the sounds—information that is absent in abruptly ending flat tones. Given that differences in perception have been reported when using different amplitude envelopes (Grassi and Pavan, 2012; Neuhoff, 1998; Schutz, 2009), we became interested in determining the prevalence of flat and percussive tones in auditory research publications. Here, we surveyed the journal Hearing Research and classified the temporal structure of sounds used into five categories: flat, percussive, click train, other, and undefined. We found 42.5% of sounds were flat (approximately 13% were click trains, 4% other, and 40% undefined). This finding is consistent with our previous surveys of Music Perception and Attention, Perception, and Psychophysics, suggesting that flat tones dominate auditory research, and the perceptual effects of more naturalistic sounds are relatively unknown and ripe for future exploration.