Search

In order to study the sound source location technology based on microphone array and realize omni-directional, efficient and convenient sound source signal location in outdoor environment, the sound source location of each three-dimensional array was numerically simulated by using beamforming sound source location algorithm and considering the topology characteristics of microphone array. In order to verify the microphone array positioning effect of different arrays, based on the beamforming algorithm, MATLAB was used to simulate the sound source positioning of three-dimensional microphone arrays with the same array element number and different distribution arrays. The results show that the positioning accuracy of three-dimensional microphone array with the same array element number and different distribution arrays is different, and the three-dimensional rotating volleyball array microphone array based on beamforming has the highest accuracy in omni-directional sound source positioning. It can be seen that the number of array elements, the size of array aperture and the spacing of array elements should be fully considered when designing microphone array. [ABSTRACT FROM AUTHOR]

Objective: To evaluate auditory spatial discrimination capabilities in patients with mild to moderately severe symmetrical sensorineural hearing loss (SNHL) and to compare the impact of different psychophysical testing methods on Minimum Audible Angle (MAA) and test duration. Methods: A total of 105 symmetrical SNHL patients aged from 18 to 60 years old were enrolled from April to July 2023, including 56 males and 49 females. They were divided into three groups based on PTA: mild, moderate, and moderately severe hearing loss, with 35 individuals in each group. Additionally, a control group of 35 individuals with normal hearing was tested, including 18 males and 17 females. Participants underwent four distinct psychophysical discrimination tests: the block up-down, 1-up/1-down, 1-up/2-down, and 1-up/3-down procedures. We recorded the MAA and test duration for each. We employed repeated measures of ANOVA to compare the MAA and test duration across different methods and groups, and Pearson's correlation to assess the relationship between MAA and degree of hearing loss. Results: MAA of sound localization in patients with symmetrical SNHL was significantly positively correlated with the degree of hearing loss ( r =0.59, P <0.01). Significant deterioration in MAA was observed as hearing loss progressed to the moderate level (PTA≥35 dBHL, P <0.01). The testing methods significantly influenced MAA and testing duration ( F =24.02, P <0.01; F =75.56, P <0.01) and the 1-up/1-down method was the quickest, averaging only (0.69±0.32) mins. Conclusions: The horizontal plane auditory spatial discrimination abilities in patients with symmetrical SNHL is impaired progressively with increasing hearing loss, notably beyond moderate hearing loss levels. Different psychophysical methods influence both MAA and test duration, the quicker 1-up/1-down method is recommended for assessing MAA in symmetrical SNHL patients.

Objectives: To investigate the outcomes of cochlear implantation in Mandarin-speaking cochlear implant (CI) users with single-sided deafness (SSD). Methods: This study was a single-center prospective cohort study. Eleven Mandarin-speaking adult SSD patients who underwent CI implantation at Capital Medical University Beijing Tongren Hospital from August 2020 to October 2021 were recruited, including 6 males and 5 females, with the age ranging from 24 to 50 years old. In a sound field with 7 loudspeakers distributed at 180°, we measured root-mean-square error(RMSE)in SSD patients at the preoperative, 1-month, 3-month, 6-month, and 12-month after switch-on to assess the improvement of sound source localization. The Mandarin Speech Perception (MSP) was used in the sound field to test the speech reception threshold (SRT) of SSD patients under different signal-to-noise locations in a steady-state noise under conditions of CI off and CI on, to reflect the head shadow effect(S SSD N NH ), binaural summation effect(S 0 N 0 ) and squelch effect(S 0 N SSD ). The Tinnitus Handicap Inventory (THI) and the Visual Analogue Scale (VAS) were used to assess changes in tinnitus severity and tinnitus loudness in SSD patients at each time point. The Speech, Spatial and Qualities of Hearing Scale(SSQ) and the Nijmegen Cochlear Implantation Scale (NCIQ) were used to assess the subjective benefits of spatial speech perception and quality of life in SSD patients after cochlear implantation. SPSS 19.0 software was used for statistical analysis. Results: SSD patients showed a significant improvement in the poorer ear in hearing thresholds with CI-on compared with CI-off; The ability to localize the sound source was significantly improved, with statistically significant differences in RMSE at each follow-up time compared with the preoperative period ( P <0.05). In the S SSD N NH condition, which reflects the head shadow effect, the SRT in binaural hearing was significantly improved by 6.5 dB compared with unaided condition, and the difference was statistically significant ( t =6.25, P =0.001). However, there was no significant improvement in SRT between the binaural hearing condition and unaided conditions in the S 0 N 0 and S 0 N SSD conditions ( P >0.05). The total score of THI and three dimensions were significant decreased ( P <0.05). Tinnitus VAS scores were significantly lower in binaural hearing compared to the unaided condition ( P <0.001). The total score of SSQ, and the scores of speech and spatial dimensions were significant improved in binaural hearing compared to the unaided condition ( P <0.001). There was no statistical difference in NCIQ questionnaire scores between preoperative and postoperative ( P >0.05), and only the self-efficacy subscore showed a significant increase( Z =-2.497, P =0.013). Conclusion: CI could help Mandarin-speaking SSD patients restore binaural hearing to some extent, improve sound localization and speech recognition in noise. In addition, CI in SSD patients could suppress tinnitus, reduce the loudness of tinnitus, and improve subjective perceptions of spatial hearing and quality of life.

Objective: This study investigates the effect of signal-to-noise ratio (SNR), frequency, and bandwidth on horizontal sound localization accuracy in normal-hearing young adults. Methods: From August 2022 to December 2022, a total of 20 normal-hearing young adults, including 7 males and 13 females, with an age range of 20 to 35 years and a mean age of 25.4 years, were selected to participate in horizontal azimuth recognition tests under both quiet and noisy conditions. Six narrowband filtered noise stimuli were used with central frequencies (CF) of 250, 2 000, and 4 000 Hz and bandwidths of 1/6 and 1 octave. Continuous broadband white noise was used as the background masker, and the signal-to-noise ratio (SNR) was 0, -3, and -12 dB. The root-mean-square error (RMS error) was used to measure sound localization accuracy, with smaller values indicating higher accuracy. Friedman test was used to compare the effects of SNR and CF on sound localization accuracy, and Wilcoxon signed-rank test was used to compare the impact of the two bandwidths on sound localization accuracy in noise. Results: In a quiet environment, the RMS error in horizontal azimuth in normal-hearing young adults ranged from 4.3 to 8.1 degrees. Sound localization accuracy decreased with decreasing SNR: at 0 dB SNR (range: 5.3-12.9 degrees), the difference from the quiet condition was not significant ( P> 0.05); however, at -3 dB (range: 7.3-16.8 degrees) and -12 dB SNR (range: 9.4-41.2 degrees), sound localization accuracy significantly decreased compared to the quiet condition (all P <0.01). Under noisy conditions, there were differences in sound localization accuracy among stimuli with different frequencies and bandwidths, with higher frequencies performing the worst, followed by middle frequencies, and lower frequencies performing the best, with significant differences (all P <0.01). Sound localization accuracy for 1/6 octave stimuli was more susceptible to noise interference than 1 octave stimuli (all P <0.01). Conclusions: The ability of normal-hearing young adults to localize sound in the horizontal plane in the presence of noise is influenced by SNR, CF, and bandwidth. Noise with SNRs of ≥-3 dB can lead to decreased accuracy in narrowband sound localization. Higher CF signals and narrower bandwidths are more susceptible to noise interference.

The incidence of single-sided deafness（SSD） is increasing year by year. Due to the hearing defects of one ear, the ability of sound localization, speech recognition in noise, and quality of life of patients with single-sided deafness will be affected to varying degrees. This article reviews the intervention effects of different types of bone conduction hearing aids in patients with single-sided deafness and asymmetric hearing loss, and the differences of intervention effects between bone conduction hearing aids, contralateral routing of signal（CROS） aids, and cochlea implant（CI）, to provide a reference for the auditory intervention and clinical treatment of single-sided deafness and asymmetric hearing loss., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

The prevalence of unilateral hearing loss（UHL） is higher, and the clinical attention to the hearing rehabilitation of UHL is not enough, resulting in many UHL patients cannot get rehabilitation timely and effectively. Severe to profound UHL（also known as single-sided deafness） patients lack binaural hearing superiority, especially the inadequate ability of sound localization, which will seriously affect their daily life and academic performance. At present, the main rehabilitation methods of UHL include various kinds of bone conduction hearing aids, vibrant soundbridge and cochlear implantation, etc. However, the rehabilitation effect of UHL patients' ability to locate the sound source is affected by the occurrence age, the type, the degree and the duration of the hearing loss. The results of rehabilitation in different literature vary greatly. This paper reviews the effects of different rehabilitation strategies on the ability of sound location and analyzes its possible causes and mechanisms., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Single-sided deafness（SSD） is a common disease. Compared with normal hearing people, unilateral deaf patients often suffer from the loss of sound source localization ability and speech recognition in complex environments due to the lack of binaural summation effect, squelch effect, spatial demasking effect, and the presence of head shadow effect. Patients' quality of life and professional activities are always poor. Therefore, this article will review the related definitions of SSD, epidemiology, hazards, and artificial hearing aids in the application of SSD patients., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Objective: To evaluate the feasibility of modified test system for sound localization (SL) in children. Methods: Modified system (6 male, 9 female) and traditional method ( 5 male, 5 female) were used for evaluation of minimum audible angle(MAA) and root-mean-square error(RMS) error of 4 to 6 years old children, and the results were compared to verify the accuracy and effectiveness of the modified test system for children sound localization.SPSS 17.0 software was used to analyze the data( t test). Results: (1) Comparison of veracity of modified system and traditional test: when tested at the positive front position using modified system, MAA and RMS error were(3.23±1.00)° and (13.68±5.18)° respectively.When using traditional method, MAA and RMS error were(3.17±0.59)°and (13.96±4.56)° respectively. No statistical differences were found between two groups( t value was 0.16, -0.14, both P >0.05). (2) Comparison of time used were as followed: when using modified system, it was (14.67±1.95) min for MAA, and (6.67±1.35) min for RMS error. When using traditional method, it was (36.30±6.81) min for MAA, and (21.00±3.50) min for RMS error. Time used were significant shorter in modified system than in traditional method ( t value was-9.78, -12.37, both P <0.05). Conclusion: Modified test system for children sound localization is useful and reliable in children's horizontal SL test.The time used of modified test system is shorter than that of traditional test system.

Cochlear implantation (CI) is a relatively new therapeutic method for patients with severe-to-profound unilateral sensorineural hearing loss. Acoustic signal can stimulate the ear directly, thus patients can gain better binaural hearing. This passage has reviewed the recent researches about CI for patients suffered from single side deafness. It can improve the ability of sound localization and speech recognition in noisy environment for patients, in addition, it may relieve tinnitus to some degree. But the long-term effect and indication selection still need further study., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

In patients with single-sided deafness (SSD), the interaural time difference and the interaural level difference signals are insufficient or missing, which result in the lack of sound localization ability and the decrease of speech comprehension in the noise environments. SSD can also cause the morphological and functional changes of the central auditory system, resulting in auditory deprivation. In early stage of the development, the auditory center is more susceptible to ambient environment and auditory inputs. It is a critical period of auditory function and morphological refinement. It is also sensitive period of central adaptability after auditory deprivation. SSD in the sensitive period of development can cause significant laterality activities of bilateral sound localization pathway. Unilateral auditory deprivation can distort tonotopic maps, disrupt the binaural integration, reorganize the neural network and change the synaptic transmission in the primary auditory cortex or sub cortex. In order to compensate for the deficiency of the interaural time difference and interaural level difference cues, the auditory pathway is used to improve the ability of sound source localization by using the spectral-shape cues remaining unchanged. In order to improve the effectiveness of the functional areas of the cortex, auditory center is also reorganized by cross-modal. However, central compensation after SSD is a double-edged sword. If SSD onset in the sensitive period, the laterality of auditory pathway will be continued and difficult to reverse by even long term bilateral hearing in the post-sensitive period. Therefore, in order to improve the understanding of the characteristics of unilateral auditory deprivation, this paper reviewed the evidence for adaptive changes in spatial hearing following a developmental hearing loss in one ear.

The aim of this review was to examine the current literature regarding application of cochlear implantation on patients with unilateral sensorineural hearing loss (USNHL) for improvement on sound localization. The literature were searched in the PubMed database with 'cochlear implantation AND single-sided deafness' or 'cochlear implantation AND unilateral deafness' as keywords. The publication date of the articles was up to 2015-2-12. A total of 12 articles were included. The results show that the ability of sound localization for most of the USNHL subjects (90%) with cochlear implantation was significantly improved than that without CI, which suggests that CI is a superior auditory rehabilitation treatment than BAHA and CROS hearing aids for patients with USNHL, because of the re-establishment of the benefits of binaural hearing. In addition, the benefit of CI for USNHL requires a period of auditory experience or training. About 30% subjects showed significantly improvement on sound localization ability after CI worked for three months. For most of the patients (90%), the sound localization ability improved after CI worked for six months. When CI worked for nine months, all the subjects would show improvement on sound localization ability. Sound localization of the USNHL subjects with a CI is based primarily on interaural level differences (ILD) while interaural time differences (ITD) provide little advantage or probably not perceptible at all. The younger subject suffers from USNHL, the stronger the plasticity of the auditory center shows, which results in more obvious degeneration of the affected side and adaptive enhancement of the contralateral side of the auditory pathway. Similarly, the longer duration of USNHL lead to more obvious degeneration of the affected side and adaptive enhancement of the contralateral side. An adaptive enhancement of auditory pathway corresponding to the healthy ear will rely more on the monaural spatial cues that available to the intact ear to improve the sound localization in the horizontal plane. Contrarily, the degeneration of auditory pathway corresponding to the USNHL may be limited to re-reorganize from auditory deprivation even after CI, which may increase the risk that a few subjects cannot re-establish the binaural benefits after CI. Therefore, patients with USNHL should accept CI as soon as possible to obtain good binaural benefits, especially for sound localization.

Objective: To compare the effect of rehabilitation of prelingual deaf children who used a cochlear implant (CI) in one ear and a hearing aids in the opposite ear while the hearing level of the opposite ears are different. Hearing ability, language ability and learning ability was included in the content. The aim of this research is to investigate better style of rehabilitation, and to offer the best help to the prelingual deaf children., Method: Accord ing to the hearing level of the ear opposite to the one wearing a cochlear implant and whether the opposite ear wear a hearing aid or not, 30 prelingual deaf children were divided into three groups, including cochlear implant with opposite severe hearing loss and hearing aid ear (CI+SHA), cochlear implant with opposite profound hearing loss and hearing aid ear (CI+PHA), cochlear implant only (CI). The effect of rehabilitation was assessed in six different times (3,6,9,12,15 and 18 months after the cochlear implants and hearing aids began to work)., Result: The longer time the rehabilitation spends, the better the hearing ability,language ability and the learning ability were. The hearing ability of CI+SHA was better than those of CI+PHA (P<0.05) and CI (P<0.05). The language ability and learning ability of CI-SHA was nearly equal to those of the other two groups., Conclusion: The prelingual deaf children should take much more time on rehabilitation. The effect of rehabilitation for prelingual deaf children who used cochlear implant in one ear and hearing aid in the other depend on the residual hearing level of the other ear. If a prelingual deaf children still has any residual hearing level in the ear opposite to the cochlear implant ear, it is better for him/her to wear a hearing aid in the ear.

Visually impaired people face many inconveniences because of the loss of vision. Therefore, scientists are trying to design various guidance systems for improving the lives of the blind. Based on sensory substitution, auditory guidance has become an interesting topic in the field of biomedical engineering. In this paper, we made a state-of-technique review of the auditory guidance system. Although there have been many technical challenges, the auditory guidance system would be a useful alternative for the visually impaired people.

Objective: To investigate the effective way to test 4-year-old children's ability of sound localization in the horizontal plane., Methods: Using minimum audible angle (MAA) measure procedure on the basis of conditioned play audiometry, sound localization test was conducted for 4-year-old children at 0 degrees , +/- 45 degrees , +/- 90 degrees , +/- 135 degrees and 180 degrees standard positions in the horizontal plane., Results: The outcome of sound localization test for 4-year-old children separately were: MAA (0 degrees ) = (3.80 +/- 0.71) degrees , MAA (-45 degrees ) = (7.70 +/- 1.27) degrees , MAA (45 degrees ) = (7.10 +/- 1.39) degrees , MAA (-90 degrees ) = (8.15 +/- 2.38) degrees , MAA (90 degrees ) = (7.61 +/- 2.47) degrees , MAA (-135 degrees ) = (8.85 +/- 2.70) degrees , MAA (135 degrees ) = (8.30 +/- 1.42) degrees , MAA (180 degrees ) = (5.20 +/- 1.27) degrees . The MAA of eight standard positions were less than 10 degrees , and the MAA (0 degrees ) was the smallest one., Conclusions: Our findings suggest that MAA test procedure on the basis of conditioned play audiometry could be used to evaluate the ability of sound localization in 4-year-old children.

Objective: To study the effects of task load on early and late components of auditory event-related potentials., Method: The subjects were 12 healthy right-handed volunteers aged 20-23 years. The stimuli were auditory signals of two kinds of tones and appeared randomly from four speakers located on the left-front, left-rear, right-front and right-rear over the head of the subject. Tasks included: a) pressing the button in response to all signals (AR); b) making location discrimination to tones from left or right (DR); c) making location discrimination to target signals (T, high-tone or low-tone) from the four sides, and make no response to non-target signals (NT). The event-related potentials (ERPs) of three tasks were compared with each other., Result: 1) The early components include P1, N1 and P2, and the late components include N2 (N2a/N2b), P3 and SW (slow wave). 2) P1 wave amplitude increased with the increase of the task load. N1 wave amplitude of SR(T)-ERPs decreased markedly compared with that of AR-ERPs and DR-ERPs, and P2 wave amplitude of AR-ERPs increased significantly compared with that of DR-ERPs and SR(T)-ERPs. P2 wave latency shortened with increase of the task load. 3) N2 (N2a/N2b), P3 and SW wave amplitudes increased with the increase of the task load., Conclusion: These data indicate that not only the late components but also the early components of auditory event-related potentials were affected by task load. The effects on the late components may be related to the change of the early component (P1) which may reflect the early activity process of the brain.