Download or read book Frequency Specificity of Contralateral Suppression of Distortion Product Otoacoustic Emissions written by Lisa Arnelle Ross and published by . This book was released on 2013 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: The frequency specificity of the contralateral suppression effect as demonstrated in DPOAEs was measured in 20 adult participants using contralateral stimuli consisting of white noise, and. 5, 1, 2, and 3 kHz tones with presentation levels of 40, 50, and 60 dB SPL. A significant suppression effect was found with white noise in the low frequencies (1.125 to 2.531 kHz) as well as higher frequencies (5.062 to 6.328 kHz). While not reaching a level of significance, 2 and 3 kHz demonstrated a similar suppression as white noise in the higher frequencies (5.062 to 6.328 kHz) and a non-significant enhancement effect was observed in the low frequencies (2.015 to 2. 812 kHz). Future studies of contralateral suppression should examine BBN with various high frequency cut offs in order to more fully examine these phenomenon.
Download or read book Frequency Specificity of Contralateral Supression of Distortion Product Otoacoustic Emissions written by Lisa Arnelle Ross and published by . This book was released on 2007 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of the Frequency Specificity of Contralateral Suppression by the Olivocochlear Bundle on Transient Evoked Otoacoustic Emissions in Adult Human Subjects written by Jeffery B. Larsen and published by . This book was released on 1995 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Comparison Between Contralateral Suppression in Cochlear Microphonics and Distortion Product Otoacoustic Emissions written by Fadi Jamil Najem and published by . This book was released on 2011 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present study examined and compared the effect of the contralateral stimulation of the auditory efferent system on the cochlear microphonics (CM) versus the distortion product otoacoustic emissions (DPOAEs). The DPOAEs and the CM were recorded from the right ear of 16 normal-hearing young female adults with and without 60 dB sound-pressure-level (SPL) broad band noise (BBN) in the left ear. DPOAEs were obtained at 0.5, 2, and 4 kHz, with L1 = 65 dB SPL and L2 = 50 dB SPL, and f2/f1 ratio = 1.2. The CM was recorded from the right tympanic membrane at 90 dB SPL using three stimuli (click and 0.5 and 2 kHz tone bursts) and two polarities (condensation and rarefaction). Results showed both suppression and enhancement of the DPOAE and the CM responses in the presence of BBN, but the effect was not statistically significant at any of the tested conditions. When the ratio of the suppression or enhancement was used, the effect was marginal for the 2 kHz TB stimulus of the CM. Results also showed a possible relation between the stimulus polarity and the type of effect on the CM. In conclusion, there is some evidence that the efferent system is involved in the suppression and enhancement of the CM, mainly at 2 kHz TB. This might be due to the nature of the CM recording from the basal turn of the cochlea. This study provided the first descriptions of the contralateral suppression of CM in humans. More research is needed to enhance the sensitivity of the CM test methodology to examine the function of the efferent system clinically.
Download or read book Otoacoustic Emissions written by Martin S. Robinette and published by Thieme. This book was released on 2011-01-01 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new edition of a best-selling text with a CD-ROM by Dr. David Kemp The new edition of the best-selling Otoacoustic Emissions: Clinical Applications provides a thorough review of the complex physiology of the ear and clinical applications of the latest research on otoacoustic emissions. The book features new chapters on such important topics as middle ear function enhanced by reflectance measurements and the use of otoacoustic emissions as a preclinical measure of susceptibility to hearing loss. Accompanying the book is a CD-ROM developed by Dr. David Kemp, Ph.D., which contains animations, movies, and interviews. The CD-ROM serves as an indispensable aid to both teaching and reviewing key concepts. From physiological phenomena to diagnostic and clinical applications, this book is a complete reference on otoacoustic emissions that will provide graduates in audiology and residents in otolaryngology and otology with all the essential information needed for research and professional practice.
Download or read book Suppression of Distortion Product Otoacoustic Emissions by Contralateral Sound written by Julian Hinvest and published by . This book was released on 1997 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Contralateral Suppression of Distortion product Otoacoustic Emissions written by Douw Van der Merwe and published by . This book was released on 2006 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Contralateral Suppression of Distortion Product Otoacoustic Emissions in Children with and Without Auditory Processing Disorders written by Blake Edward Butler and published by . This book was released on 2008 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of the Auditory Efferents on Acoustic Distortion Products in Human Subjects written by Deirdre Mary Williams and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Specificity of the Midial Olivocochlear Effect on Frequency and Word Discrimination in Noise written by David Glen Price and published by . This book was released on 2013 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ipsilateral or contralateral activation of the MOC pathway is known to result in modifications of OHC mobility. These changes impact on the cochlear active process and the ability to detect low intensity sound and can be observed through OAE measurements. Previous studies have shown that the presence of this effect in situations where sound is masked by noise can result in an improvement of discriminatory ability. The tonotopical nature of the MOC has been observed anatomically, but its physiological relevance remains uncertain. This thesis aimed to investigate the possible changes in MOC effect when contralaterally activated by noise of varying frequency spectrum. It was hypothesised that when attempting to distinguish tonal patterns of 4 or 5 kHz presented in a BBN, participants would perform better when contralaterally stimulated with noise that contained the same frequency range. Using DPOAE measurements in the presence of contralateral noise, it was also hypothesised that suppression of emissions caused by OHC modification could be used as relative measures of MOC strength. These measures were then referenced against performance in psychoacoustic discrimination tasks looking at the effect of varying frequency contralateral stimulation on word and frequency pattern discrimination. Results showed a significant relationship between the presence of contralateral noise and discrimination ability in the psychoacoustic tests. However, no change in DPOAE suppression was observed when tested in the presence of different contralateral stimulation (F (30, 600) = 0.742, p=0.840). No significant interaction was found between DPOAE measurements and psychoacoustic results. Despite steps to remove its influence, activation of the acoustic reflex was statistically significant in several findings which complicated the interpretation of the study's results. The benefit observed with contralateral stimulation in psychoacoustic testing suggested the presence and activation of the MOC pathway, despite the inability of DPOAE findings to confirm its suppression of the cochlear active process. The proportional benefit of using frequency relevant noise as an activator of contralateral MOC effect were potentially observed but unable to be confirmed by physiological data.
Download or read book Relations of Race and Gender to Distortion Product Otoacoustic Emissions written by Lara L. Gingerich and published by . This book was released on 1998 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Bone Conduction Transducer Placement on Distortion Product Otoacoustic Emissions written by Julie L. Hazelbaker and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The purpose of this study was to develop a technique to determine the magnitude of bone conducted sound in the cochlea when stimuli are delivered from three different locations on the head. Distortion product otoacoustic emissions (DPOAE) at 1000 and 2000 Hz were used as tools to determine cochlear response to stimuli introduced via air conduction and bone conduction in three subjects. The bone conduction transducer was moved to three head locations (ipsilateral mastoid, contralateral mastoid and forehead). The intensity of the emissions elicited was compared. The differences in DPOAE magnitude created by varying the location of the bone conduction transducer were compared with behavioral threshold differences with the same transducers at the same locations. It was assumed that results of behavioral measures would provide a prediction of the relationship between air and bone conducted DPOAE. However, in the current study, this was not the case. Behavioral bone conduction threshold data did not predict differences in DPOAE at different bone conduction transducer locations. This was a somewhat surprising result and should be considered further in future studies examining the properties of DPOAE elicited by bone conduction. Additionally, a wide band noise masker was introduced to the non-test ear when bone conducted stimuli were introduced to make DPOAE and behavioral test conditions as similar as possible. No great suppression effects were noted across subjects for either frequency. This was likely due to the shape and intensity of the contralateral masked used.
Download or read book Characterizing the 2f1 f2 Distortion product Otoacoustic Emission and Its Generators Measured from 2 to 20 KHz in Humans written by Laura Elizabeth Dreisbach and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The cochlea produces recordable acoustic energy (otoacoustic emissions). These otoacoustic emissions occur spontaneously or can be evoked. Distortion-product otoacoustic emissions (DPOAEs) are produced by the intermodulation between the primary stimulus tones (f2 > f1) and occur at frequencies not present in the evoking acoustic stimuli. The 2f1-f2 DPOAE is well characterized for frequencies less than 8 kHz in humans; however, most basilar membrane measurements in animals have been made at higher frequencies. Thus, DPOAE measurements were extended to the higher frequency range of human hearing. High-frequency DPOAEs were characterized by how the DPOAE level varied with primary frequency separations (f2/f1) and stimulus levels and how the group delay estimate of the DPOAE varied with primary frequency. It was concluded that high-frequency DPOAEs continued the patterns seen for low-frequency DPOAEs, indicating that high-frequency DPOAEs are the result of the same biological process responsible for low-frequency DPOAEs.
Download or read book Test Retest Reliability of Distortion Product Otoacoustic Emissions in the High Frequency Range written by Hoi-Yee Iris Ng and published by . This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Test-retest Reliability of Distortion Product Otoacoustic Emissions in the High Frequency Range" by Hoi-yee, Iris, Ng, 伍凱怡, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of dissertation entitled Test-retest Reliability of Distortion Product Otoacoustic Emissions in the High Frequency Range submitted by NG, Hoi-Yee Iris for the degree of Master of Science in Audiology at the University of Hong Kong in May 2002 In the current research study, distortion product otoacoustic emissions (DPOAEs) were measured in 35 young Chinese adults (61 ears) with normal audiometric thresholds using an ILO96 OAE system with the default DP-gram protocols as well as user-defined DP spectrum protocols in the high frequency range. Two series of retest were conducted 20 minutes and an average of 15 days later, and the resolution setting for the DP-gram measurements was varied between 1 to 8 points per octave in each test series. Transient evoked otoacoustic emissions (TEOAEs) were also recorded in each test series for comparison purposes. Test-retest partial correlation and standard error of measurement (SEM) were computed to reflect the test-retest reliability of the OAE amplitudes, noise floor and signal-to-noise ratio. Results suggested that OAE amplitudes in the default frequency range (1 to 6 kHz) between test and retest were highly correlated with an average correlation coefficient of 0.85 and SEM was found to be an average of 2.4 dB, while signal-to-noise ratio and noise floor yielded lower correlation coefficients and higher SEMs. OAE amplitudes in the higher frequency range of 6.5 to 7 kHz were also significantly correlated between test and retest (correlation coefficient ranged from 0.74 to 0.80) with SEM from 2.7 to 3.5 dB. Yet DPOAEs at 8 kHz were present with a positive signal-to-noise ratio in only one-third of ears, were less test-retest correlated, and the amplitude revealed a high SEM of 5 dB. No apparent difference was demonstrated among various resolution settings and between short- and long- term retest. This implies that DPOAEs in the high frequency range (6.5 to 7 kHz) could be a potential clinical tool for monitoring cochlear functioning in cases such as exposure to ototoxic medication or noise. vii DOI: 10.5353/th_b2701474 Subjects: Otoacoustic emissions Hearing - Measurement
Download or read book The Cochlea written by Peter Dallos and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 561 pages. Available in PDF, EPUB and Kindle. Book excerpt: Knowledge about the structure and function of the inner ear is vital to an understanding of vertebrate hearing. This volume presents a detailed overview of the mammalian cochlea from its anatomy and physiology to its biophysics and biochemistry. The nine review chapters, written by internationally distinguished auditory researchers, provide a detailed and unified introduction to sound processing in the cochlea and the steps by which the ensuing signals are prepared for the central nervous system.
Download or read book Auditory Efferent System New Insights from Cortex to Cochlea written by Paul H. Delano and published by Frontiers Media SA. This book was released on 2016-09-06 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main function of the sensory systems is the transducing of external stimuli into bioelectrical signals, which are conducted through afferent pathways from sensory epithelia to the brain. However, it is known that descending projections are ubiquitous in the different sensory modalities, and in the case of auditory efferents connect the cerebral cortex with sensory receptor cells. Several functions have been attributed to the efferent system, including protection to acoustic trauma, unmasking of auditory stimuli in background noise, balance of interaural sensitivity and some cognitive functions like modulation of cochlear sensitivity during selective attention to auditory or visual stimuli. In addition there is evidence of a possible involvement of the efferent system in the etiology or treatment of some clinical pathologies like tinnitus. In this e-book, entitled “Auditory Efferent System: New Insights from Cortex to Cochlea”, we aimed to give an overview of the advances concerning the descending projections from the auditory cortex to subcortical nuclei and the olivocochlear system. In addition, different theoretical proposals of efferent functions are presented. We think that this e-book is an important contribution to the understanding of the efferent system in mammals, merging auditory-cortex literature with studies performed in the olivocochlear system.
Download or read book Measures of Distortion Product Otoacoustic Emissions and Frequency Resolution in Clinically Normal Hearing Subjects with a History of Noise Exposure written by Janet Caffee and published by . This book was released on 1997 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:
