Yuexin Cai

Auditory Spatial Discrimination and the Mismatch Negativity Response in Hearing-Impaired Individuals

The aims of the present study were to investigate the ability of hearing-impaired (HI) individuals with different binaural hearing conditions to discriminate spatial auditory-sources at the midline and lateral positions, and to explore the possible central processing mechanisms by measuring the minimal audible angle (MAA) and mismatch negativity (MMN) response. To measure MAA at the left/right 0°, 45° and 90° positions, 12 normal-hearing (NH) participants and 36 patients with sensorineural hearing loss, which included 12 patients with symmetrical hearing loss (SHL) and 24 patients with asymmetrical hearing loss (AHL) [12 with unilateral hearing loss on the left (UHLL) and 12 with unilateral hearing loss on the right (UHLR)] were recruited. In addition, 128-electrode electroencephalography was used to record the MMN response in a separate group of 60 patients (20 UHLL, 20 UHLR and 20 SHL patients) and 20 NH participants. The results showed MAA thresholds of the NH participants to be significantly lower than the HI participants. Also, a significantly smaller MAA threshold was obtained at the midline position than at the lateral position in both NH and SHL groups. However, in the AHL group, MAA threshold for the 90° position on the affected side was significantly smaller than the MMA thresholds obtained at other positions. Significantly reduced amplitudes and prolonged latencies of the MMN were found in the HI groups compared to the NH group. In addition, contralateral activation was found in the UHL group for sounds emanating from the 90° position on the affected side and in the NH group. These findings suggest that the abilities of spatial discrimination at the midline and lateral positions vary significantly in different hearing conditions. A reduced MMN amplitude and prolonged latency together with bilaterally symmetrical cortical activations over the auditory hemispheres indicate possible cortical compensatory changes associated with poor behavioral spatial discrimination in individuals with HI.

Effect of the combination of balloon Eustachian tuboplasty and tympanic paracentesis on intractable chronic otitis media with effusion

OBJECTIVE To evaluate the effect of the combination of balloon Eustachian tuboplasty (BET) and tympanic paracentesis (TP) on intractable chronic otitis media with effusion (COME). METHODS Ninety patients with intractable COME were included and randomly assigned to three groups: BET only (30 patients), BET+paracentesis (30 patients), and paracentesis only (30 patients). Otic endoscopic findings and tympanograms were recorded before the surgery and at the month 1, month 3, and month 6 follow-up evaluations. RESULTS Both the BET only and BET+paracentesis groups achieved better outcomes than the paracentesis group. The BET+paracentesis group exhibited better otic endoscopic scores than the BET only group (p<0.05) at 1month post-operation. However, no significant difference was found at month 3 or month 6 post-operation. No significant difference in the tympanograms was observed between these two groups at month 1, month 3, or month 6 post-operation. The otic endoscopic sign scores improved from month 1 to month 6 in the BET only group and from month 1 to month 3 in the BET+paracentesis group. The conversion of type B tympanograms improved from month 1 to month 6 in the BET and BET+paracentesis groups but not in the paracentesis only group. CONCLUSIONS Our results suggested that the combination of BET and TP was effective for intractable COME and can help shorten the recovery period for middle ear effusion.

Visual cortex activation decrement following cochlear implantation in prelingual deafened children

OBJECTIVE Visual take-over of the auditory cortex in prelingual deaf children has been widely reported. However, there have been few studies on visual cortex plasticity after cochlear implantation (CI). In this study, we investigated the hypothesis that extrinsic auditory stimulation following CI in prelingual deafened children can induce visual cortex plasticity. METHOD Visual evoked potentials (VEPs) were recorded in 37 CI children (4 groups with different use times) and 8 control subjects, in response to sound and nonsound stimuli. Latency and amplitude were analyzed for the P1, N1 and P2 components on the Oz electrode. Comparisons of VEP were conducted between the sound and nonsound stimuli and among different groups in order to view evidence of visual cortex reorganization. RESULTS The latency of the P2 component was significantly longer at the occipital site (Oz) in CI 0M than those in the other four groups. After the effect of age was excluded, a significant negative correlation was found between CI usage and P2 latency of nonsound stimuli. Occipital P1N1 latency and P1 amplitude were not affected by group or stimulus category. However, the N1 and P2 amplitudes were significantly larger in response to a sound stimulus than to a nonsound stimulus. CONCLUSION Our findings suggest that P2 latency develops with CI usage and may be a biomarker of visual cortex plasticity.

Higher-Order Brain Network Analysis for Auditory Disease

Auditory diseases such as deafness and tinnitus have been plaguing people for a long time. On the one hand, although cochlear implantation may serve as a cure for deafness to some degree, the mechanism of developmental neuroplasticity in the auditory and visual systems has not been well understood. On the other hand, there is still no cure for tinnitus, and investigating the cause and then developing the cure of tinnitus is particularly necessary. EEG signals provide us insights into these auditory diseases and have been widely studied for developing the cure of auditory diseases, in particular from the brain network perspective. However, most of the existing methods either simply utilize lower-order features of the brain network at the level of local connections within selected brain regions or fail to analyze the EEG signals from the brain region connectivity perspective. In this paper, based on the EEG signals, we develop a new higher-order brain network analysis method termed HBNmining (higher-order brain network mining) based on the weighted motifs and colored motifs for deepening the understanding of the auditory diseases. In particular, after constructing brain network from EEG signals, both the weighted motifs and the colored motifs are extracted, from which subject classification and brain region connectivity analysis can be conducted respectively. The results have confirmed the effectiveness of our method, which may be helpful for clinical treatment of auditory diseases.

Plasma brain-derived neurotrophic factor levels are increased in patients with tinnitus and correlated with therapeutic effects.

Tinnitus is the perception of sound without an external source and is known to be associated with altered neuronal excitability in the auditory system. Tinnitus severity can be assessed by various psychometric instruments and there is no objective measures developed to evaluate tinnitus severity and therapeutic effects so far. Brain-derived nerve growth factor (BDNF) is believed in playing a key role in regulating neuronal excitability in the brain. To determine whether BDNF correlates with tinnitus induction and severity, we described plasma BDNF levels in patients with tinnitus and healthy controls and evaluated the correlation between plasma BDNF levels and tinnitus severity measured by Tinnitus Handicap Inventory (THI) and Visual Analog Scale (VAS). Moreover, alteration of plasma BDNF levels before and after tinnitus retraining therapy (TRT) in patients with severe tinnitus was also analyzed. We found plasma BDNF levels were elevated in patients with tinnitus compared with healthy controls. In addition, plasma BDNF levels in patients with severe tinnitus were decreased significantly after effective TRT. However, plasma BDNF levels were not correlated with tinnitus loudness and tinnitus severity measured by THI and VAS. These findings support plasma BDNF as a marker for activity changes in the auditory system and could possibly evaluate therapeutic effects in patients with tinnitus.

Development and validation of a Chinese music quality rating test

Abstract Objective: The present study aims to develop and validate a Chinese music quality rating test (MQRT). Design: In Experiment 1, 22 music pieces were initially selected and paired as a ‘familiar music piece’ and ‘unfamiliar music piece’ based on familiarities amongst the general public in the categories of classical music (6), Chinese folk music (8), and pop music (8). Following the selection criteria, one pair of music pieces from each music category was selected and used for the MQRT in Experiment 2. In Experiment 2, the MQRT was validated using these music pieces in the categories ‘Pleasantness’, ‘Naturalness’, ‘Fullness’, ‘Roughness’, and ‘Sharpness’. Study sample: Seventy-two adult participants and 30 normal-hearing listeners were recruited in Experiments 1 and 2, respectively. Results: Significant differences between the familiar and unfamiliar music pieces were found in respect of pleasantness rating for folk and pop music pieces as well as in sharpness rating for pop music pieces. The comparison of music category effect on MQRT found significant differences in pleasantness, fullness, and sharpness ratings. Conclusion: The Chinese MQRT developed in the present study is an effective tool for assessing music quality.

Mechanisms of music perception and its changes in hearing impaired people

Abstract Objective: This review aims to highlight the key elements of music perception and its mechanisms in normal hearing people and people with hearing impairments. Design: A systematic literature search was conducted using the National Library of Medicines search service – PubMed (website: http://www.ncbi.nlm.nih.gov/sites/entrez), with the subject headings ‘Music perception’, ‘Hearing impairment’ and ‘Normal hearing people’ or ‘Cochlear implant’ or ‘Hearing aid’. Results: The key evidence available and the mechanisms of poor music perception in hearing impaired people with hearing devices were reviewed, including hearing aid (HA) alone, cochlear implant (CI) alone or bimodal (HA+ CI) stimulation. People with hearing impairment have limited ability to fully utilize fine temporal structure and frequency selectivity, and consequently musical pitch, melody and timbre perception in people with hearing impairment is significantly impaired. Conclusion: The poor ability to accurately perceive music for hearing aids users is mainly due to the damaged cochlea and device distortion, whereas cochlear implant recipients typically have poor music perception because of reduced extraction of temporal and spectral information in music.

Multi-View Intact Space Learning for Tinnitus Classification in Resting State EEG

Tinnitus is a common but obscure auditory disease to be studied, and there are still in the lack of effective methods developed to treat tinnitus universally. Although electroencephalogram (EEG) is widely applied to the diagnosis of tinnitus, there are few machine learning methods developed to classify tinnitus patients from healthy people based on the EEG data. Moreover, there is still room for improving the classification performance due to the insufficient existing studies. Therefore, in order to improve the performance of classification based on the EEG data, we introduce a multi-view intact space learning method to characterize the EEG signals by feature extraction in a latent intact space. Considering the fact that there are only a small number of subjects available for study, we conduct the classification for valid segments of EEG data of each subject. In this way, the dataset can be enlarged and the classification performance can be improved. By combining different views of EEG data, a considerable result is achieved on classification by using Support Vector Machine classifier, with accuracy, recall, precision, F1 to be 99.23, 99.72, 98.97, 99.34% respectively. This proposed method is an effective and objective method to classify the tinnitus patients from healthy people, further researches are needed to explore the machine learning method in classification and prediction of the effectiveness of tinnitus interventions based on the EEG response of tinnitus individuals.

Brain Network Regional Synchrony Analysis in Deafness

Deafness, the most common auditory disease, has greatly affected people for a long time. The major treatment for deafness is cochlear implantation (CI). However, till today, there is still a lack of objective and precise indicator serving as evaluation of the effectiveness of the cochlear implantation. The goal of this EEG-based study is to effectively distinguish CI children from those prelingual deafened children without cochlear implantation. The proposed method is based on the functional connectivity analysis, which focuses on the brain network regional synchrony. Specifically, we compute the functional connectivity between each channel pair first. Then, we quantify the brain network synchrony among regions of interests (ROIs), where both intraregional synchrony and interregional synchrony are computed. And finally the synchrony values are concatenated to form the feature vector for the SVM classifier. What is more, we develop a new ROI partition method of 128-channel EEG recording system. That is, both the existing ROI partition method and the proposed ROI partition method are used in the experiments. Compared with the existing EEG signal classification methods, our proposed method has achieved significant improvements as large as 87.20% and 86.30% when the existing ROI partition method and the proposed ROI partition method are used, respectively. It further demonstrates that the new ROI partition method is comparable to the existing ROI partition method.

Prevalence and factors associated with tinnitus: data from adult residents in Guangdong province, South of China

Abstract There is a lack of national studies on tinnitus in China and data based on a large sample size from multiple areas of the country. A cross-sectional study was carried out in Guangdong province from October 2015 to February 2016. In the study, tinnitus was defined as the presence of ringing, buzzing or other sounds in the ears in the past one year. Fourteen districts in Guangdong Province were selected as the first-level cluster by using the sampling method of probability proportional to size (PPS). Two sub-districts in each first-level cluster were randomly selected as the second-level cluster by PPS method. The sample consisted of 3705 eligible people aged over 18 years old, which were also selected by the PPS methods. The prevalence of tinnitus was 10.4% in Guangdong Province. Age, region, educational background, hearing impairment, ear trauma, otitis media and self-health report were the main risk factors for tinnitus. Tinnitus is a common condition and a large population suffers from tinnitus in Guangdong province, south of China. Greater public awareness and understanding of the associated factors are required for further interventions of prevention and management of tinnitus in China.