Search Results
Results 251 - 300 of 1320
< 1 2 3 4 5 6 7 8 9 10 11 >
Gerstein Edmund - - 2008
A comprehensive series of underwater psychoacoustic tests was conducted to measure the hearing abilities of West Indian manatees. Pure tones, complex and real world sounds were presented to manatees under controlled acoustical conditions. The results from 30 000 threshold trials measured their audiogram, temporal integration, critical ratios, MMAs and directional ...
Gerstein Edmund - - 2008
Ultrasonic hearing thresholds above 46 kHz were first measured with a test-sophisticated manatee in 1997. Using staircase and method of constants paradigms, pure tones (38-96 kHz) were presented in force-choice two-alternative tests. Repeatable detection thresholds were measured at 38, 46, 56, 66, and 76 kHz. These extended ultrasonic hearing results ...
Keidser Gitte - - 2008
This study aimed to determine whether gain adaptation occurs, and at which frequency bands, among new hearing aid (HA) users. Fifty new and 26 experienced HA users were fitted with three listening programs (NAL-NL1 and NAL-NL1 with low- and high-frequency cuts) in the same hearing instrument family. Real-life gain preferences ...
Korhonen Petri - - 2008
PURPOSE: To demonstrate the usability of new acoustic cues provided by a commercial hearing aid using linear frequency transposition. The importance of auditory training in realizing the benefit was evaluated. RESEARCH DESIGN: Quasi-experimental study design. All subjects were tested both with conventional amplification and with linear frequency transposition before and ...
Pandol Stephen J - - 2008
The article presents a brief overview of the responses of the GI tract and its associated pancreatic and biliary systems to a meal. These responses are specifically regulated by complex and interacting neural, hormonal, and parcrine pathways. Stimuli for various responses are multiple and include anticipation, senses of olfaction, taste ...
Gaddam Anupa - - 2008
The objective of this study was to improve the sensitivity of ABR recordings in newborns via a procedure that utilizes the ear canal as a recording site. Conventional recordings were compared to ear canal recordings of the ABR in 45 normally-hearing newborns who passed their newborn hearing screening. Responses were ...
Nandi Subroto S - - 2008
Noise is the insidious of all industrial pollutants, involving every industry and causing severe hearing loss in every country in the world. Exposure to excessive noise is the major avoidable cause of permanent hearing impairment. Worldwide, 16% of the disabling hearing loss in adults is attributed to occupational noise, ranging ...
Gerostergiou E - - 2008
OBJECTIVE: To evaluate the clinical and audiometric characteristics of noise by an one-engine Cessna (1300-1750 RPM), by ultra light aircrafts and different types of air modeling products which induce hearing loss in air modeling members of Aviation club of Larissa in Greece. MATERIAL-METHODS: During the past 2 years members in ...
Heise Stephan J - - 2008
Audiograms measured with a high frequency resolution often show quasi-periodic ripples of up to 15 dB in normal-hearing listeners. This fine structure of the threshold in quiet is commonly associated with the active processes in the cochlea. Therefore its absence is discussed in the literature as an indicator of cochlear ...
Luts Heleen - - 2008
OBJECTIVES: The purpose of this study was to evaluate the risks of uncontrolled use of an objective detection criterion in recording auditory steady-state responses (ASSRs). The influence of decisions such as when to accept a response and stop the recording was assessed by analyzing the number of false- and true-detected ...
Clement C I - - 2009
AIM: Matrix perimetry uses frequency-doubling technology (FDT) incorporated into a 5 degrees test target. This permits testing of the same number of locations within a defined visual field as standard automated perimetry (SAP) and may improve performance compared with original FDT perimetry. This study investigates the performance of Humphrey Matrix ...
Stelmachowicz Patricia G PG Boys Town National Research Hospital, 555 N. 30th Street, Omaha, NE 68131, USA. - - 2008
Recent studies from the authors' laboratory have suggested that reduced audibility in the high frequencies (because of the bandwidth of hearing instruments) may play a role in the delays in phonological development often exhibited by children with hearing impairment. The goal of the current study was to extend previous findings ...
Valentine Susie - - 2008
PURPOSE: To investigate the effects of hearing loss on auditory stream segregation of broadband inharmonic sounds. METHOD: Auditory stream segregation by listeners with normal and impaired hearing was measured for 6-component inharmonic sounds ("A" and "B") using objective and subjective methods. Components in the A stimuli ranged between 1000 and ...
Zhou Jiangfeng - - 2008
We propose a simple and effective way to reduce the losses in left-handed metamaterials by manipulating the values of the effective parameters R, L, and C. We investigate the role of losses of the short-wire pairs and the fishnet structures. Increasing the effective inductance to capacitance ratio, L/C, reduces the ...
Jonas Brannstrom K - - 2008
The purpose of this study was to measure changes in intensity and pitch matches to better assess disease activity in fluctuating hearing loss. Long-term suprathreshold audiometry was carried out at home on a subject with a unilateral fluctuating low-frequency hearing loss during a period when the subject demonstrated no symptoms ...
Swanepoel DeWet - - 2009
The inclusion of the auditory steady-state response (ASSR) into test-batteries for objective audiometry has allowed for clinical comparisons with the most widely used procedure, the auditory brainstem response (ABR). The current study describes ASSR and ABR thresholds for a group of infants and young children with various types and degrees ...
Wong Lena L N - - 2008
CONCLUSION: Speech thresholds measured using Cantonese Hearing in Noise Test (CHINT) and cortical evoked response audiometry (CERA) thresholds were highly correlated with pure-tone behavioral results. Both tests are considered to provide good estimates of hearing thresholds and can be employed to confirm the degree of hearing loss in Cantonese-speaking communities. ...
Horwitz Amy R - - 2008
PURPOSE: This study was designed to determine the extent to which high-frequency amplification helped or hindered speech recognition as a function of hearing loss, gain-frequency response, and background noise. METHOD: Speech recognition was measured monaurally under headphones for nonsense syllables low-pass filtered in one-third-octave steps between 2.2 and 5.6 kHz. ...
Kulesza Randy J RJ - - 2008
The superior olivary complex (SOC) is a cluster of nuclei situated in the caudal brainstem tegmentum that forms an essential component of the auditory pathway. The SOC includes two principal nuclei, the medial and lateral superior olives (MSO and LSO respectively), that have clear roles in sound source localization. Surrounding ...
Shrivastav Mini N - - 2008
For a single stimulus such as shaped broadband noise, spectral-shape discrimination can vary based on the nature of the spectral feature that is being detected. For example, Shrivastav et al. (2006) found a significant difference in thresholds for broadband noise with a narrow localized spectral peak and those with a ...
Suzuki Yo Iti - - 2008
Sensorineural hearing-impaired people have difficulty in hearing sounds not only because of the increased hearing threshold, but also because of their reduced dynamic range of hearing (loudness recruitment), as well as the large and extensive masking resulting from the reduced frequency selectivity, especially masking by which middle-frequency and high-frequency components ...
Seidler Hannes - - 2008
All hearing aids and cochlea implants have algorithm to improve the speech intelligibility. The idea is to share human speech and noise to find different ratings. The result should be easier to understand by impaired people. On the market there are big efforts to recognize speech and to separate it ...
Lin Y-H YH Department of Otolaryngology, Buddhist Dalin Tzu Chi General Hospital, Chiayi, - - 2009
For various medico-legal and financial reasons, some patients may clinically demonstrate an exaggerated hearing loss that varies in degree, nature and laterality. The purpose of this study was to evaluate whether multi-channel auditory steady-state response measurement can be used as an objective test of auditory thresholds in adults with sensorineural ...
Kim Keehoon - - 2008
Active noise reduction (ANR) for aircrew hearing protection in harsh noise environments such as military and civilian flight operations requires a high-performance, microsized driver that provides not only high acoustic power, at least 130 dB SPL, but also high fidelity sound quality, especially in low-frequency ranges below 100 Hz. A ...
Strelcyk Olaf - - 2008
Hearing-impaired people often experience great difficulty with speech communication when background noise is present, even if reduced audibility has been compensated for. Other impairment factors must be involved. In order to minimize confounding effects, the subjects participating in this study consisted of groups with homogeneous, symmetric audiograms. The perceptual listening ...
Lechner Walter - - 2008
Otophysine fish possess Weberian ossicles, which connect the swimbladder to the inner ear and improve hearing ability. There is a high diversity in the morphology of the swimbladder and Weberian apparatus in catfishes, which might affect hearing. We have examined these structures in representatives of six families with large, single ...
Jurado Carlos A - - 2008
In order to evaluate loudness or audibility of complex sounds, knowledge of the auditory filter characteristics is necessary. At low frequencies, where both the threshold of hearing and dynamic range become considerably frequency dependent, care must be taken to account for this both in the psycho-acoustical model and the methodological ...
Narins Peter - - 2008
Among the vertebrates, only microchiropteran bats, cetaceans and some rodents are known to produce and detect ultrasonic (US) frequencies for the purpose of communication andor echolocation, suggesting that this capacity may be restricted to mammals. We have recently provided the first evidence of ultrasonic communication in an amphibian - the ...
Green Tim - - 2008
For some cochlear implant (CI) users a contralateral hearing aid provides significantly improved speech perception. Important factors in the bimodal transmission of speech spectral information are likely to include the extent to which the frequency selectivity of residual hearing allows additional place-coded channels, and mismatches between frequency-to-place maps across modalities. ...
Tan Chin-Tuan CT Department of Otolaryngology, New York University School of Medicine, New York, NY 10016, USA. - - 2008
All hearing aids and communication devices introduce nonlinear distortion. The perception of distortion by hearing-impaired subjects was studied using artificial controlled distortions of various amounts and types. Subjects were asked to rate the perceived quality of distorted speech and music. Stimuli were subjected to frequency-dependent amplification as prescribed by the ...
Finneran James J - - 2008
Auditory evoked potentials are being increasingly applied to more advanced studies of marine mammal hearing, such as frequency selectivity, temporal processing, and temporary threshold shift (TTS). In this study, both behavioral and electrophysiological techniques were used to measure TTS in a bottlenose dolphin exposed to 20-kHz tones. Behavioral hearing thresholds ...
Jansen E J M - - 2009
OBJECTIVES: An investigation of the hearing status of musicians of professional symphony orchestras. Main questions are: (1) Should musicians be treated as a special group with regard to hearing, noise, and noise related hearing problems (2) Do patterns of hearing damage differ for different instrument types (3) Do OAE have ...
Chung King - - 2008
As advanced signal processing algorithms have been proposed to enhance hearing protective device (HPD) performance, it is important to determine how directional microphones might affect the localization ability of users and whether they might cause safety hazards. The effect of in-the-ear microphone directivity was assessed by measuring sound source identification ...
Hatzopoulos Stavros - - 2008
BACKGROUND: The objective of the study was to evaluate hearing threshold errors induced by the use of a new acoustical protocol (Cochlea-Scan). MATERIAL/METHODS: Thirty-five normally hearing and 30 hearing-impaired adults were used in the study. Hearing threshold levels were assessed by pure tone audiometry (PTA) and the Cochlea-Scan (Fischer-Zoth/Natus) DPOAE ...
Mrena Roderik - - 2008
Conclusion. Hearing protection regulations have improved the hearing test results of soldiers in the Finnish Defense Forces. Objectives. To investigate the effect of revised regulations regarding usage of hearing protectors of professional soldiers in the Finnish Defense Forces. Subjects and methods. The medical records of non-commissioned officers and officers examined ...
Nachtigall P E - - 2008
This is the first report of an underwater audiogram from a dolphin in a capture-and-release scenario. Two bow-riding white-beaked dolphins Lagenorhynchus albirostris (a female and a male) were captured using the hoop-net technique in Faxaflói Bay, Iceland. The dolphins were transferred to a stretcher and hoisted into a plastic research ...
Ricketts Todd A - - 2008
PURPOSE: One factor that has been shown to greatly affect sound quality is audible bandwidth. Provision of gain for frequencies above 4-6 kHz has not generally been supported for groups of hearing aid wearers. The purpose of this study was to determine if preference for bandwidth extension in hearing aid ...
Feng Albert S - - 2008
The concave-eared torrent frogs (Amolops tormotus) have highly unusual ear morphology--in males the eardrums are embedded deep inside ear cavities. In collaboration with our colleagues we investigated the functional significance of this morphological feature in hearing. Sound recordings in the field showed that males of A. tormotus produce diverse bird-like ...
Kastelein Ronald A - - 2008
World-wide, underwater background noise levels are increasing due to anthropogenic activities. Little is known about the effects of anthropogenic noise on marine fish, and information is needed to predict any negative effects. Behavioural startle response thresholds were determined for eight marine fish species, held in a large tank, to tones ...
Harada Hirofumi - - 2008
Through pure-tone audiometry, we studied the course of hearing recovery in 24 ears of 20 men (ages 18-48 years) who had acute acoustic sensorineural hearing loss (ASHL). All subjects were members of the Japanese Self-Defense Force. The hearing level in 5 ears returned to normal, the hearing level of 13 ...
Yildirim Ilhami - - 2007
The aim of this study was to investigate the effects of noise on hearing, lipid peroxidation and antioxidant enzymes in textile workers. Thirty textile workers exposed to high noise 105 dB (A) in a textile factory, and 30 healthy male volunteers in our hospital as a control group were included ...
Jenstad Lorienne M - - 2007
OBJECTIVES: This study had two related purposes: first, to define the range of optimal ear canal levels of aided speech in both high frequency and low frequency regions for adults, using both subjective and objective definitions of optimal; and second, to determine whether a prescribed frequency response, such as that ...
DiGiovanni Jeffrey J - - 2007
PURPOSE: This study compared the speed, false-alarm rate, and participant preference of different response methods (raising a hand, pushing a response button, and giving an oral response) for measuring pure-tone thresholds. METHOD: Thirty female university students with normal hearing participated. Response method order was randomly assigned to 6 different groups. ...
Emadi Gulam - - 2008
This report describes stiffness and best frequency measurements obtained in vitro from the basilar membrane of the gerbil cochlea at the onset of hearing, during hearing maturation, and after hearing has matured. Our stiffness data constitute the first direct experimental evidence of developmental stiffness changes in the basal and middle ...
Christensen-Dalsgaard Jakob J Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark. - - 2008
Tympanic hearing is a true evolutionary novelty that appears to have developed independently in at least five major tetrapod groups-the anurans, turtles, lepidosaurs, archosaurs and mammals. The emergence of a tympanic ear would have increased the frequency range and sensitivity of hearing. Furthermore, tympana were acoustically coupled through the mouth ...
Sandhu Sunil - - 2007
We introduce a light-stopping process that uses dynamic loss tuning in coupled-resonator delay lines. We demonstrate via numerical simulations that increasing the loss of selected resonators traps light in a zero group velocity mode concentrated in the low-loss portions of the delay line. The large dynamic range achievable for loss ...
Ménard Mikaël - - 2008
The present study investigates the relationship between auditory steady-state responses (ASSRs) and loudness growth function. ASSR amplitudes were compared to the perceived loudness level at frequencies of 500 and 2000Hz in 11 normal-hearing subjects. As a first step, loudness growth function was estimated for the two test frequencies. Then ASSR ...
Ronsse Lauren M - - 2007
Examining the effects of mechanical system noise on worker performance and perception for normal-hearing persons has been an area of previous research; this study extends this research area to include hearing-impaired subjects. The goal is to determine if persons with hearing impairments respond similarly to seven different mechanical system background ...
Espinoza-Varas Blas - - 2007
Owing to reduced afferent input from high characteristic-frequency hair cells, high-frequency sensorineural hearing loss (SNHL) reorganizes the tonotopic maps in the central auditory nervous system: Map expansion is observed in the midfrequencies and map contraction in the high frequencies. Does the relative weighting of mid and high frequency information depend ...
Shinn Jennifer B - - 2007
The auditory steady state response (ASSR) has recently gained attention with respect to estimates of hearing sensitivity and configuration of hearing loss. The present investigation compared behavioral thresholds to estimated ASSR thresholds in subjects with confirmed CANS lesions to determine if this population can be accurately evaluated with ASSR techniques. ...
< 1 2 3 4 5 6 7 8 9 10 11 >