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The Effects of Auditory Selective Attention on Contralateral Suppression of Stimulus-Frequency Otoacoustic Emissions
Soheila Rostami,Akram Pourbakht,Mohammad Kamali,Bahram Jalaee
Audiology , 2011,
Abstract: Background and Aim: To date, the function of auditory efferent system remains unclear. There is evidence that medial olivocochlear bundle receives descending input from the cortex. In this study, the effect of auditory selective attention on stimulus-frequency otoacoustic emissions (SFOAE) was analyzed to investigate the modification of peripheral auditory system by auditory cortex activity in frequency specific mode.Methods: Thirty-six normal hearing adult subjects with their age ranging from 18 to 30 years (mean age: 21.9 years) participated in this cross-sectional study. Contralateral suppression of stimulus-frequency otoacoustic emissions was recorded in the right ear at 2 KHz. In order to eliminate the auditory attention, subjects were instructed to read a text. Besides, in order to evaluate the effect of auditory attention on contralateral suppression, subjects were instructed to detect target tones in background noise at 1000, 2000, and 4000 KHz.Results: A significant increase at contralateral suppression of stimulus-frequency otoacoustic emissions was observed in auditory selective attention conditions (p≤0.001). The largest magnitude of stimulus-frequency otoacoustic emissions suppression was seen at 2 KHz.Conclusion: The results of this study indicated that the activities of medial olivocochlear bundle enhanced by contralateral auditory selective attention increase the magnitude of stimulus-frequency otoacoustic emissions suppression. In fact, these results provided evidence for influence of auditory cortex on the peripheral auditory system via corticofugal pathways in a frequency specific way.
Ear Recognition and Occlusion  [PDF]
B. S. El-Desoky,M. Z. Rashad,Mahmoud M. Eid,M. El-Kady
International Journal of Computer Science & Information Technology , 2013,
Abstract: Personal identification using 2D ear images still has many problems such as occlusion mostly caused byhair, earrings, and clothes. To avoid this problem, we propose to divide the ear image into non-overlappingequal divisions and identify persons through these non-occluded parts separately and then combine outputsof the classification of these parts in abstract, rank, and measurement level fusion. Experimental resultsshow that the increasing of recognition rate through combining small parts of non-occluded divisions ofear image.
The Effect of Acoustic Reflex on Contralateral Suppression of Transient-Evoked Otoacoustic Emissions
Farzaneh Zamiri Abdollahi,Abdolreza Sheibanizadeh,Jalal Sameni
Audiology , 2012,
Abstract: Background and Aim: Contralateral suppression of transient evoked otoacoustic emissions (TEOAEs) test evaluates the efferent auditory system. In this test, acoustic reflex is an important confounding variable. In recent years, application of this test is growing especially in children suspect to central auditory processing disorder. Therefore, the magnitude of influence of this confounding variable on the suppression of TEOAEs should be made clear. The aim of this study was to investigate the impact of acoustic reflex on contralateral suppression of TEOAEs.Methods: This research was performed on 39 normal-hearing adults of both sexes and of 18-26 years of age. Tests were used for the determination of interaural attenuation (IA), acoustic reflex, TEOAEs and contralateral suppression of TEOAEs.Results: TEOAEs amplitudes and their contralateral suppression were significantly higher in females and males respectively (p=0.01). The amount of TEOAEs suppression before reflex activity ranged between 2000 to 3000 Hz. Activation of acoustic reflex significantly increased the magnitude of suppression in all frequency bands (p≤0.01) and maximum suppression occurred in 500 to 1000 Hz.Conclusion: For achieving accuracy of clinical findings, clinicians should always use suppressant levels lower than the acoustic reflex threshold. It is recommended that different norms for males and females be used in contralateral suppression of TEOAEs.
The Effect of Learning Disability on Contralateral Suppression of Otoacoustic Emissions in Primary Students  [PDF]
Saeid Sarough Farahani,Mansoureh Adel Ghahraman,Marzieh Amiri,Shohreh Jalaei
Audiology , 2006,
Abstract: Background and Aim: One of the most significant complaints of children with learning disability (LD) is difficulty in understanding speech in the presence of background noise. Different studies have shown that the medial olivocochlear bundle(MOCB) may play a role in hearing in noise. The MOCB function can be evaluated by the contralateral suppression of tone burst evoked otoacoustic emissions (TBEOAEs).The aim of the present study was to evaluate frequency specifications of MOCB by the contralateral suppression of TBEOAEs at 1,2,3 and 4 KHz in response to contralateral white noise in LD students. Materials and Methods: This case-control study was conducted on 34 LD students aged 7-11 years and 31 normal students matched for age.The contralateral suppression of TBEOAEs was evaluated by comparing TBEOAEs amplitudes with and without contralateral white noise. Results: In the absence of noise there was no significant difference between TBEOAEs amplitudes of two groups. In the presence of noise significant decrease was seen in TBEOAEs amplitudes at 1,2,3 and 4 KHz in both groups. In LD students the amount of this decrement at 1,2 and 4 KHz was lower than in the normal students. Conclusion: A significant diminished suppression effect at 1,2 and 4 KHz in LD students indicates that at these frequency regions MOCB function was reduced. Therefore it suggests that the assessment of MOCB by evaluating the suppression effect of TBEOAEs included in the test battery approach used in the diagnostic of LD students.
Study on suppression of otoacoustic emissions: lateral domain
Oliveira, Jerusa Roberta Massola de;Fernandes, Candido Fernandes;Costa Filho, Orozimbo Alves;
Brazilian Journal of Otorhinolaryngology , 2011, DOI: 10.1590/S1808-86942011000500002
Abstract: a pon stimulation by contralateral, ipsilateral or bilateral noise, the medial olivocochlear efferent tract changes the amplitude of otoacoustic emissions relative to the tested ear, reducing or removing it; this resulted in a reduction/suppression effect of otoacoustic emissions. differences in patterns of elimination/reduction of otoacoustic emissions between ears have been documented worldwide; there are, however, no brazilian studies investigating the effect of lateral dominance. aims: to compare the effect of the presence of deletion/reduction of otoacoustic emissions and their amplitude relative to lateral dominance in normal hearing adults. methods: a clinical and experimental study. the sample comprised 75 individuals. the methodology was conventional - linear click intensity of 60 db spl; white noise was contralateral stimulation at 60 db spl. description of results: there were no statistically significant differences between right and left ear results, in terms of asymmetry of the degree of otoacoustic emissions and the presence of suppression/reduction. conclusion: there is no lateral dominance in the degree of otoacoustic emissions in the presence of suppression/reduction in the study population.
Effects of changes in dynamic characteristics of the middle ear on transient-evoked otoacoustic emissions  [PDF]
?piri? Sanja,?piri? Predrag,Vranje? Dalibor,Aleksi? Aleksandra
Medicinski Pregled , 2011, DOI: 10.2298/mpns1110439s
Abstract: Transient-evoked otoacoustic emissions are transmitted through the middle ear. The purpose of this study was to investigate the effects of dynamic properties of the transmission system on the measurability of transient otoacoustic emissions. The authors analyzed the presence of transient otoacoustic emissions in 48 children with serous otitis media regarding the tympanogram, presence and type of effusion and pure tone average findings. The results obtained in this research show the predominant absence of transient otoacoustic emissions in patients with type B tympanogram (69.1%) especially if the effusion is mucoid (77.5%) with the hearing loss of 15 decibel hearing level. This research shows that disorders in dynamic characteristics of the middle ear in patients with serous otitis obstruct the transmission of acoustic energy and affect the measurability of transient otoacoustic emissions, especially if the effusion is mucoid and hearing loss of 15 decibel hearing level.
Contralateral acoustic suppression of transient evoked otoacoustic emissions: Activation of the medial olivocochlear system  [PDF]
Komazec Zoran,Filipovi? Danka,Milo?evi? Du?an
Medicinski Pregled , 2003, DOI: 10.2298/mpns0304124k
Abstract: Medial olivocochlear pathway represents the final part of efferent acoustic pathway which comes from the superior olivary complex ending at outer hair cells. Activation of medial olivocochlear system (MOCS) alters the cochlear output decreasing the travelling wave within cochlea. Stimulation of MOCS provides protection against moderate levels of noise, encoding noise signals as well as selecting hearing attention. Activation of MOCS can be performed using contralateral acoustic stimulation. The principal result of presentation of contralateral acoustic stimulation during screening of transient evoked otoacoustic emission (TEOAE) is an attenuation of the TEOAE amplitude. Thirty-eight ears were examined in this study: twenty-eight ears from 14 normal-hearing adults and 10 patients with unilateral deafness. Healthy subjects were exposed to contralateral broad-band noise of various intensities (40, 30, 20 and 10 dB SL), as well as 30 dB SL pure tone stimulation (1 kHz and 4 kHz). A decrease of TEOAE amplitudes during contralateral stimulation with 40 and 30 dB SL broad-band noise and pure tones was established. This effect was a result of MOCS activation. A greater intensity of contralateral stimulation evoked greater decrease of TEOAE amplitude; stimulation with broad-band noise caused greater attenuation than with pure tone stimulation. Contralateral stimulation of deaf ears in the group with unilateral deafness was also performed. Statistically significant difference between TEOAE amplitude before and during contralateral stimulation was not established. This circumstance explains that activation of MOCS and consequent reduction of outer hair cells motility is very possibly caused by contralateral acoustic stimulation. Apart from studying physiological significance of efferent auditory system, results of this and similar studies can be used for production of hearing aids improving speech discrimination in noisy environment.
Efeito da estimula o acústica contralateral nas medidas temporais das emiss es otoacústicas Effect of contralateral acoustic stimulation in temporal measures of otoacoustic emissions  [cached]
Vanessa Nogueira Leme,Renata Mota Mamede Carvallo
Revista CEFAC , 2009,
Abstract: OBJETIVO: comparar o nível de resposta e o tempo de latência das emiss es otoacústicas sem e com apresenta o de ruído contralateral. MéTODOS: foram avaliados 30 indivíduos, com idade entre 18 e 30 anos, sem queixas auditivas e com presen a de emiss es otoacústicas por produto de distor o. Analisou-se o nível de resposta e latência das emiss es otoacústicas por meio do programa Latencygram, com e sem apresenta o de ruído contralateral tipo "White noise". RESULTADOS: houve diminui o significante nos níveis de resposta das emiss es otoacústicas com apresenta o de ruído contralateral, confirmando o efeito de supress o relacionado com a a o do sistema eferente; contudo, n o houve diferen a significante nos valores de latência das emiss es otoacústicas. CONCLUS O: o sistema eferente atua apenas na modula o dos níveis de resposta das emiss es otoacústicas, contudo n o interfere nas medidas temporais das mesmas. PURPOSE: compare the otoacoustic emissions response level and latency in two situations: with and without contralateral competitive noise. METHODS: thirty individuals between eighteen and thirty-year-old, with no auditory complaints and presence of otoacoustic distortion product emissions were evaluated. The latency and the response level of otoacoustic emissions was evaluated using the Latencygram program. The test was performed in two different situations: with and without contralateral competitive white noise. RESULTS: the results demonstrated a significant reduction in otoacoustic emissions response levels with contralateral noise, proving the otoacoustic suppression effect associated with olivocochlear efferent system action. However, there was no significant difference in otoacoustic emissions latency. CONCLUSION: the efferent system may act only in otoacoustic emissions response level modulation but it does not interfere in otoacoustic emissions latency.
Balloon Occlusion of the Contralateral Iliac Artery to Assist Recanalization of the Ipsilateral Iliac Artery in Total Aortoiliac Occlusion: A Technical Note  [PDF]
Abdel Aziz A. Jaffan
Case Reports in Radiology , 2013, DOI: 10.1155/2013/647850
Abstract: Endovascular recanalization of chronic total aortoiliac occlusion is technically challenging. Inability to reenter the true aortic lumen, following retrograde iliac recanalization, is one of the most common causes of failure. We describe a case of a total aortoiliac occlusion where balloon occlusion of the right common iliac artery, following its recanalization from a brachial approach, was used to facilitate antegrade recanalization of the occluded contralateral left common iliac artery. 1. Introduction Chronic obstruction of the aortic bifurcation, involving to a varying degree and extent both the infrarenal aortic and common iliac arteries (CIAs), can result in a triad of symptoms consisting of intermittent claudication, absent or diminished peripheral pulses, and impotence. Classically described in males, the anatomic pattern of obstruction is equally common in males and females [1]. The onset is mainly between 40 and 60 years of age, and the disease can lead to severe impairment of walking capacity, rest pain, and wheelchair dependence [1, 2]. Aortobifemoral bypass has been considered the gold standard for treating chronic aortoiliac occlusions [3], but results of endovascular recanalization of the iliac arteries now approach those of aortobifemoral bypass with reduced morbidity and mortality and shorter hospitalization [4]. The Trans-Atlantic Inter-Society Consensus for the management of Peripheral Arterial Disease (TASC II) document classifies total aortoiliac occlusion as type D, with surgery as the treatment of choice [3]. Nowadays, endovascular therapy is increasingly performed in patients with extensive aortoiliac disease, including total aortoiliac occlusion [1]. We describe a technique that might facilitate the recanalization of chronic total iliac occlusion, during endovascular recanalization of a total aortoiliac occlusion. 2. Case Description The patient was a 53-year old female with multiple cardiovascular factors, including hypertension, hypercholesterolemia, diabetes mellitus, coronary artery disease, and history of heavy smoking (60 pack-years; quit 3 years ago), who presented with bilateral lower extremity intermittent claudication, right worse than left, forcing her to stop after 3 minutes of walking. On physical examination, her bilateral femoral, popliteal, dorsalis pedis and posterior tibialis pulses were not palpable. At rest, her ankle-brachial index (ABI) measured 0.57 on the right and 0.58 on the left. She underwent a computed tomographic angiography (CTA) that showed complete occlusion of the distal abdominal aorta,
Supress?o contralateral das emiss?es otoacústicas nos indivíduos com zumbido
Fávero, Mariana Lopes;Sanchez, Tanit Ganz;Bento, Ricardo Ferreira;Nascimento, Andreia Ferreira;
Revista Brasileira de Otorrinolaringologia , 2006, DOI: 10.1590/S0034-72992006000200012
Abstract: introduction: the medial olivocochlear bundle effect is studied through the suppression of otoacoustic emissions and seems to be influenced by the laterality of the central nervous system, presenting no symmetry between right and left ear. a dysfunction of this bundle may be involved in the generation of tinnitus, although this fact was not confirmed. objectives: study the suppression of distortion product otoacoustic emissions in tinnitus patients. material and method: a case-controlled study involving 44 tinnitus patients from the tinnitus group of the ent department of the university of s?o paulo medical school and 44 controls who underwent distortion product otoacoustic emissions testing with and without contralateral noise. only the results from the right ears from both groups were compared. results: there was a relationship between the presence of tinnitus and the absence of suppression at all frequencies studied (or>2.1). conclusion: there was a correlation between diminished effectiveness of the medial olivocochlear bundle and the presence of tinnitus.
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