The deployment of vehicle micro-motors has witnessed an expansion owing to the progression in electrification and intelligent technologies.However,some micro-motors may exhibit design deficiencies,component wear,assem...The deployment of vehicle micro-motors has witnessed an expansion owing to the progression in electrification and intelligent technologies.However,some micro-motors may exhibit design deficiencies,component wear,assembly errors,and other imperfections that may arise during the design or manufacturing phases.Conse-quently,these micro-motors might generate anomalous noises during their operation,consequently exerting a substantial adverse influence on the overall comfort of drivers and passengers.Automobile micro-motors exhibit a diverse array of structural variations,consequently leading to the manifestation of a multitude of distinctive auditory irregularities.To address the identification of diverse forms of abnormal noise,this research presents a novel approach rooted in the utilization of vibro-acoustic fusion-convolutional neural network(VAF-CNN).This method entails the deployment of distinct network branches,each serving to capture disparate features from the multi-sensor data,all the while considering the auditory perception traits inherent in the human auditory sys-tem.The intermediary layer integrates the concept of adaptive weighting of multi-sensor features,thus affording a calibration mechanism for the features hailing from multiple sensors,thereby enabling a further refinement of features within the branch network.For optimal model efficacy,a feature fusion mechanism is implemented in the concluding layer.To substantiate the efficacy of the proposed approach,this paper initially employs an augmented data methodology inspired by modified SpecAugment,applied to the dataset of abnormal noise sam-ples,encompassing scenarios both with and without in-vehicle interior noise.This serves to mitigate the issue of limited sample availability.Subsequent comparative evaluations are executed,contrasting the performance of the model founded upon single-sensor data against other feature fusion models reliant on multi-sensor data.The experimental results substantiate that the suggested methodology yields heightened recognition accuracy and greater resilience against interference.Moreover,it holds notable practical significance in the engineering domain,as it furnishes valuable support for the targeted management of noise emanating from vehicle micro-motors.展开更多
BACKGROUND Stapes ankylosis is a rare cause of conductive hearing loss,and stapes suprastructure fixation is extremely rare with fewer than 30 reported cases.Patients usually visit the clinic with non-progressive cond...BACKGROUND Stapes ankylosis is a rare cause of conductive hearing loss,and stapes suprastructure fixation is extremely rare with fewer than 30 reported cases.Patients usually visit the clinic with non-progressive conductive hearing loss that typically began in the early years of life.CASE SUMMARY Herein,we report a case of a 37-year-old female with an isolated stapedial suprastructure fixation.The patient presented with unusual fluctuating auditory symptoms of tinnitus,ear fullness and mixed hearing loss.Pre-operative temporal bone computed tomography findings and operative findings revealed an isolated stapedial suprastructure fixation with monopod stapes caused by elongated pyramidal eminence.The hearing threshold recovered completely,and fluctuating auditory symptoms disappeared after the surgery.CONCLUSION This is the first report of stapedial suprastructure fixation with fluctuating auditory symptoms.Successful results are expected with surgical treatment.展开更多
In anurans, calling behaviour is strongly seasonal and circadian. Previous studies have revealed that a uditory sensitivity in frogs exhibits seasonal plasticity, and electroencephalographic signals exhibit highly cor...In anurans, calling behaviour is strongly seasonal and circadian. Previous studies have revealed that a uditory sensitivity in frogs exhibits seasonal plasticity, and electroencephalographic signals exhibit highly correlated circadian patterns;of which, the circadian rhythm remains unknown. In this study,the circadian rhythm and intersexual differences of auditory sensitivity were tested in the Emei music frog(Nidirana daunchina). This was achieved by comparing thresholds and latencies of auditory brainstem responses(ABRs) evoked by tones and clicks stimuli between male and female frogs during the day and at night,respectively. Our results revealed that both auditory thresholds and latencies had no differences between day and night except the la tencies in 3.5–4.0 kHz frequencies. However, the thresholds of tone pip evoked ABRs differed significantly between male and female frogs from 2.5 to 5.0 kHz. This demonstrated that the auditory sensitivity of Emei music frogs exhibits sexual dimorphism at high frequencies, with female frogs exhibiting greater auditory sensitivity than that of male frogs. Simultaneously, the power spectra of male advertisement calls are matched well with the frequency range of auditory sensitivity in male and female frogs,which supports the matched filter hypothesis. Our study enhances the understanding of circadian plasticity and sexual dimorphism of auditory sensitivity in frogs.展开更多
Transcranial electrical stimulation(tES)is a non-invasive nerve stimulation technique that modulates changes in neural activities in cerebral cortex through a weak current of specific intensity(and frequency).It has b...Transcranial electrical stimulation(tES)is a non-invasive nerve stimulation technique that modulates changes in neural activities in cerebral cortex through a weak current of specific intensity(and frequency).It has become a valuable tool for the study of human behavior and cognitive neurophysiological processes.As a brain stimulation technology with broad development prospects,it is not mature enough in the field of human auditory research.However,the research on tES has obtained preliminary results in regulating motor ability.This article mainly introduces the effects of tES and auditory steady state response on auditory,and the applications of tES in auditory diseases.By summarizing and discussing tES during auditory processing as comprehensively as possible,the potential application value of tES in the treatment of auditory diseases could be illustrated.展开更多
Objective:The effect of long term auditory deprivation on Cortical Auditory Evoked Potentials(CAEPs)especially in human models is not well explored.Hence,the current study was aimed to investigate the effects of long-...Objective:The effect of long term auditory deprivation on Cortical Auditory Evoked Potentials(CAEPs)especially in human models is not well explored.Hence,the current study was aimed to investigate the effects of long-term auditory deprivation and stimulability of auditory cortex in non habilitated congenitally deaf adolescents and adults using CAEPs.Methods and Results:A total of 27 non-habilitated congenitally deaf adolescents/adults with age and gender matched normal hearing adolescents/adults participated in the study.The congenitally deaf group was fitted with high gain hearing aids(first fit).Further,the CAEPs were recorded.The obtained CAEP components were assessed for group effect,source and topographical differences.The between group analysis for CAEP responses showed a significant difference only for P2 latency and amplitude.The source analysis revealed that,in the normal hearing group for CAEPs,the sources were within the temporal regions.However,in the congenitally deaf group,along with the temporal cortex,the bilateral prefrontal cortex also was activated.Conclusion:The findings revealed that it is possible to stimulate and evoke a matured CAEP response from a long deprived auditory system with adequate acoustic stimulation.The presence of CAEP responses is indicative of the functionality of the innate auditory pathway and the crossmodal plasticity in long auditory deprived individuals.展开更多
The amplitudes and latencies of auditory brainstem evoked response(ABR)were recorded at both high(50/s)and low(10/s)click rates as sound stimuli before andafter the guinea pigs were exposed to variant intensity noise....The amplitudes and latencies of auditory brainstem evoked response(ABR)were recorded at both high(50/s)and low(10/s)click rates as sound stimuli before andafter the guinea pigs were exposed to variant intensity noise.The maximum amplitude ofwave V increased significantly,but those of wave Ⅰ,Ⅲ,and Ⅳ decreased significantly afterexposure to 110 dB noise for 20 or 30 min.The wave Ⅴ latency recorded at 50/s clickrate was shorter in every group after exposure.The changes of wave V latency recordedat 10/s click rate were complex,it was shorter after exposure to 95 dB or 105 dB for 10min;no change was found after exposure to 110 dB for 10 min,but it was longer initiallyand then became shorter after exposure to 110 dB noise for 30 min.The difference valueof wave V latency from 10/s to 50/s was negatively correlated with the noise intensityand exposure time.The more intense noise stimuli and the longer time,the less the differ-ence value became.The results indicate that the auditory bralnstem center was affectedby intense noise,and it is helpful to use difference value of wave V latency to analysis thefunction of brainstem center after exposure to noise.展开更多
Objectives To investigate changes in evoked potentials and structure of the guinea pig cochleae during whole cochlear perfusion with glutamate. Methods CM, CAP, DPOAE, and ABR were recorded as indicators of cochlear f...Objectives To investigate changes in evoked potentials and structure of the guinea pig cochleae during whole cochlear perfusion with glutamate. Methods CM, CAP, DPOAE, and ABR were recorded as indicators of cochlear functions during whole cochlear perfusion. The morphology of the cochlea was studied via transmission electron microscopy. Results There were no significant changes in DPOAE amplitude before and after glutamate perfusion. CM I/O function remained nonlinear during perfusion. ABR latencies were delayed following glutamate perfusion. The average CAP threshold was elevated 35 dB SPL following glutamate perfusion.. The OHCs appeared normal, but the IHCs and afferent dendrites showed cytoplasmic blebs after glutamate perfusion. Conclusions While being a primary amino acid neurotransmitter at the synapses between hair cells and spiral ganglion neurons, excessive glutamate is neurotoxic and can destroy IHCs and spiral ganglion neurons. The technique used in this study can also be used to build an animal model of auditory neuropathy.展开更多
Objective To analyze the characteristics of auditory brainstem response(ABR) in presbycusis patients elder than 90 years. Methods Fourteen presbycusis patients elder than 90 years(presbycusis group, 91.1.4±1.3 ye...Objective To analyze the characteristics of auditory brainstem response(ABR) in presbycusis patients elder than 90 years. Methods Fourteen presbycusis patients elder than 90 years(presbycusis group, 91.1.4±1.3 years, 26 ears) and 9 normal-hearing young adults(control group, 22.7±1.2 years, 18 ears) participated in the study. Alternative click-evoked ABRs were recorded in both groups. The peak latency(PL) of peak I,Ⅲ, and V, and the inter-peak latency(IPI) of I-Ⅲ, Ⅲ-V, and I-V were compared between groups. Results In elder presbycusis patients, the occurrence rate of peak I and Ⅲ were both 76.9%, and that of peak V was84.6%. In presbycusis group, the peak latencies of I, Ⅲ, V were significantly longer than that of control group(P<0.001). There was no significant difference between groups in the IPI of peak I-I Ⅲ(P=0.298,peak Ⅲ-V(P=0.254) and peak I-V(P=0.364). Conclusions Auditory brainstem responses in presbycusis patients elder than 90 years showed worse wave展开更多
To characterize the patterns of ABR waves in tree shrews, we must understand the hearing sensitivity and auditory function of healthy adult tree shrews. Fifteen tree shrews(30 ears) were stimulated with clicks and ton...To characterize the patterns of ABR waves in tree shrews, we must understand the hearing sensitivity and auditory function of healthy adult tree shrews. Fifteen tree shrews(30 ears) were stimulated with clicks and tone-pips at 11 different frequencies from 1 to 60 kHz. The ABR waves were recorded and analyzed. The ABR consisted of five to seven positive waves in the first 10 ms after a click stimulus, and the average hearing threshold of component III was 27.86 ± 3.78 dB SPL. Wave III was the largest and most clear. The ABR threshold was related to the tone-pip sitmulus by a "U" shaped curve. The sensitive frequency was approximately 8 kHz in tree shrews. The latencies systematically decreased with increasing stimulus frequencies. The ABR amplitudes of wave III increased as the sound pressure level increased. All of these results provide an empirical basis for future studies of hearing diseases in tree shrews.展开更多
Transcranial direct current stimulation(tDCS)has been reportedly beneficial for different neurodegenerative disorders.tDCS has been reported as a potential adjunctive or alternative treatment for auditory verbal hallu...Transcranial direct current stimulation(tDCS)has been reportedly beneficial for different neurodegenerative disorders.tDCS has been reported as a potential adjunctive or alternative treatment for auditory verbal hallucination(AVH).This study aims to review the effects of tDCS on AVH in patients with schizophrenia through combining the evidence from randomized clinical trials(RCTs).The databases of PsycINFO(2000–2019),PubMed(2000–2019),EMBASE(2000–2019),CINAHL(2000–2019),Web of Science(2000–2019),and Scopus(2000–2019)were systematically searched.The clinical trials with RCT design were selected for final analysis.A total of nine RCTs were eligible and included in the review.Nine RCTs were included in the final analysis.Among them,six RCTs reported a significant reduction of AVH after repeated sessions of tDCS,whereas three RCTs did not show any advantage of active tDCS over sham tDCS.The current studies showed an overall decrease of approximately 28%of AVH after active tDCS and 10%after sham tDCS.The tDCS protocols targeting the sensorimotor frontal-parietal network showed greater treatment effects compared with the protocols targeting other regions.In this regard,cathodal tDCS over the left temporoparietal area showed inhibitory effects on AVHs.The most effective tDCS protocol on AVHs was twice-daily sessions(2 mA,20-minute duration)over 5 consecutive days(10 sessions)with the anode over the left dorsolateral prefrontal cortex and the cathode over the left temporal area.Some patient-specific and diseasespecific factors such as young age,nonsmoking status,and higher frequencies of AVHs seemed to be the predictors of treatment response.Taken together,the results of tDCS as an alternative treatment option for AVH show controversy among current literatures,since not all studies were positive.However,the studies targeting the same site of the brain showed that the tDCS could be a promising treatment option to reduce AVH.Further RCTs,with larger sample sizes,should be conducted to reach a conclusion on the efficacy of tDCS for AVH and to develop an effective therapeutic protocol for clinical setting.展开更多
The current randomized controlled trial was performed at the China Rehabilitation Science Institute, China to test the hypothesis that musical auditory stimulation has positive effects on the autonomic nervous system ...The current randomized controlled trial was performed at the China Rehabilitation Science Institute, China to test the hypothesis that musical auditory stimulation has positive effects on the autonomic nervous system of patients with disorder of consciousness.Although past studies have recommended that patients with disorder of consciousness listen to patient-preferred music, this practice is not universally accepted by researchers.Twenty patients with severe disorder of consciousness listened to either therapist-selected(n = 10, 6 males and 4 females;43.33 ± 18.76 years old) or patient-preferred(n = 10, 5 males and 5 females, 48.83 ± 18.79 years old) musical therapy, 30 minutes/day, 5 times/week for 6 weeks.The results showed no obvious differences in heart rate variability-related parameters including heart rate, standard deviation of normal-to-normal R-R intervals, and the root-mean-square of successive heartbeat interval differences of successive heartbeat intervals between the two groups of patients.However, percentage of differences exceeding 50 ms between adjacent normal number of intervals, low-frequency power/high-frequency power, high-frequency power norm, low-frequency power norm, and total power were higher in patients receiving therapist-selected music than in patients receiving their own preferred music.In contrast, this relationship was reversed for the high-frequency power and very-low-frequency band.These results suggest that compared with preferred musical stimulation, therapist-selected musical stimulation resulted in higher interactive activity of the autonomic nervous system.Therefore, therapist-selected musical stimulation should be used to arouse the autonomic nervous system of patients with disorder of consciousness.This study was approved by the Institutional Ethics Committee of China Rehabilitation Research Center, China(approval No.2018-022-1) on March 12, 2018 and registered with the Chinese Clinical Trial Registry(registration number Chi CTR1800017809) on August 15, 2018.展开更多
Acquired atresia of the external auditory canal(EAC)is a rare cause of conductive hearing loss.It has been traditionally classified into 4 categories:traumatic,post-operative,neoplastic and inflammatory.Post-inflammat...Acquired atresia of the external auditory canal(EAC)is a rare cause of conductive hearing loss.It has been traditionally classified into 4 categories:traumatic,post-operative,neoplastic and inflammatory.Post-inflammatory acquired auditory canal atresia is thought to be the result of chronic and repetitive infectious bouts affecting the auditory canal.Nevertheless,the underlying pathophysiology of this disorder is yet to be fully elucidated.Current data fail to clearly state the impact that certain underlying systemic disorders may have on the EAC.The possible association to metabolic disturbances such as iron deficiency is also emphasized.In the light of these findings,this analysis can be used to improve the classification of this entity thereby standardizing the assessment of therapeutic approaches.展开更多
AIM To provide an updated of recent findings about efficacy of cognitive-behavior therapy(CBT) in reduction of command hallucinations.METHODS Pub Med/MEDLINE,Cochrane Library,the Cumulative Index to Nursing and Allied...AIM To provide an updated of recent findings about efficacy of cognitive-behavior therapy(CBT) in reduction of command hallucinations.METHODS Pub Med/MEDLINE,Cochrane Library,the Cumulative Index to Nursing and Allied Health Literature,PsycI NFO,Clinical Trial.gov searches were performed using the keywords "hallucinations","behavioural therapy" and " cognitive therapy" in order to identify relevant articles published during the years of 2011 to 2016.No language limits were used.Studies conducted within control group,reviews,editorials,were excluded.Data on efficacy,acceptability and tolerability were extracted by three authors independently.Disagreements were resolved in a consensus meeting or by another reviewer.RESULTS A total of eight articles were eligible for inclusion.Two are randomized clinical trials(RCTs) and six are observational studies.The two RCTs included showed a greater efficacy of CBT compared to standard care on auditory hallucinations(AHs).Nevertheless,they considered different CBT models,particularly Treatment of Resistant Command Hallucinations and Cognitive Therapy for Command Hallucinations.As regards non RCT-studies,all papers included showed reduction on frequency and severity of AHs and distress related to them.However,the lack of content details within non-RCTs studies decreased their comparability.In terms of predictive variables,our findings show that negative symptoms at baseline appeared to be the strongest predictor of the treatment efficacy.Indeed,negative symptoms showed a significant negative correlation on outcome.CONCLUSION Although more conclusive studies are still needed,we found some preliminary evidence for the efficacy of CBT in the treatment of command hallucinations.展开更多
The development and plasticity of central auditory system can be influenced by the change of peripheral neuronal activity. However, the molecular mechanism participating in the process remains elusive. Brain-derived n...The development and plasticity of central auditory system can be influenced by the change of peripheral neuronal activity. However, the molecular mechanism participating in the process remains elusive. Brain-derived neurotrophic factor(BDNF) binding with its functional receptor tropomyosin receptor kinase B(TrkB) has multiple effects on neurons. Here we used a rat model of auditory deprivation by bilateral cochlear ablation, to investigate the changes in expression of BDNF and Trk B in the auditory cortex after auditory deprivation that occurred during the critical period for the development of central auditory system. Reverse transcription-quantitative polymerase chain reaction(RTqPCR) and immunohistochemistry methods were adopted to detect the m RNA and protein expression levels of BDNF and TrkB in the auditory cortex at 2, 4, 6 and 8 weeks after surgery, respectively. The change in the expression of BDNF and TrkB mRNAs and proteins followed similar trend. In the bilateral cochlear ablation groups, the BDNF-TrkB expression level initially decreased at 2 weeks but increased at 4 weeks followed by the reduction at 6 and 8 weeks after cochlear removal, as compared to the age-matched sham control groups. In conclusion, the BDNF-TrkB signaling is involved in the plasticity of auditory cortex in an activity-dependent manner.展开更多
In this invited review I provide a selective overview of recent research on brain mechanisms and cognitive processes involved in auditory hallucinations. The review is focused on research carried out in the "VOIC...In this invited review I provide a selective overview of recent research on brain mechanisms and cognitive processes involved in auditory hallucinations. The review is focused on research carried out in the "VOICE" ERC Advanced Grant Project, funded by the European Research Council, but I also review and discuss the literature in general. Auditory hallucinations are suggested to be perceptual phenomena, with a neuronal origin in the speech perception areas in the temporal lobe. The phenomenology of auditory hallucinations is conceptualized along three domains, or dimensions; a perceptual dimension, experienced as someone speaking to the patient; a cognitive dimension, experienced as an inability to inhibit, or ignore the voices, and an emotional dimension, experienced as the "voices" having primarily a negative, or sinister, emotional tone. I will review cognitive, imaging, and neurochemistry data related to these dimensions, primarily the first two. The reviewed data are summarized in a model that sees auditory hallucinations as initiated from temporal lobe neuronal hyper-activation that draws attentional focus inward, and which is not inhibited due to frontal lobe hypo-activation. It is further suggested that this is maintained through abnormal glutamate and possibly gamma-amino-butyric-acid transmitter mediation, which could point towards new pathways for pharmacological treatment. A final section discusses new methods of acquiring quantitative data on the phenomenology and subjective experience of auditory hallucination that goes beyond standard interview questionnaires, by suggesting an iP hone/iP od app.展开更多
Auditory verbal hallucination(AVH)is emphasized as a pathological hallmark of schizophrenia.Neuroimaging studies provide evidence linking AVH to overlapping functional abnormalities in distributed networks.However,no ...Auditory verbal hallucination(AVH)is emphasized as a pathological hallmark of schizophrenia.Neuroimaging studies provide evidence linking AVH to overlapping functional abnormalities in distributed networks.However,no clear conclusion has still been reached.This study aimed to further explore the brain activity of patients with schizophrenia having AVH from both local activity(LA)and functional connectivity(FC)insights,while excluding confounding factors from other positive symptoms.A total of 42 patients with AVH(AVH patients group,APG),26 without AVH(non-AVH patients group,NPG),and 82 normal controls(NC)underwent resting-state functional magnetic resonance imaging(fMRI).LA measures,including regional homogeneity(ReHo)and fractional amplitude of low-frequency fluctuations(fALFF),and FC measures were evaluated to understand the neuroimaging mechanism of AVH.APG showed increased ReHo and fALFF in the bilateral putamen(Put)compared with NPG and NC.FC analysis(using bilateral putamen as seeds)revealed that all patients showed abnormal FC of multiple resting state network regions,including the anterior and post cingulate cortex,middle frontal gyrus,inferior parietal gyrus,and left angular gyrus.Interestingly,APG showed significantly decreased FC of insula extending to the superior temporal gyrus and inferior frontal gyrus compared with NPG and NC.The present findings suggested a significant correlation of abnormal LA and dysfunctional putamen-auditory cortical connectivity with the neuropathological mechanism of AVH,providing evidence for the functional disconnection hypothesis of schizophrenia.展开更多
Objective To report outcomes of cochlear implantation (CI) in a child with auditory neuropathy spectrum disorder (ANSD) and to provide preliminary clinical evidence of the efficacy of CI in ANSD patients.Methods A 4-y...Objective To report outcomes of cochlear implantation (CI) in a child with auditory neuropathy spectrum disorder (ANSD) and to provide preliminary clinical evidence of the efficacy of CI in ANSD patients.Methods A 4-year-old boy with diagnosed auditory neuropathy spectrum disorder (ANSD) received implantation of a Nucleus CI24R after an unsatisfactory trial of amplification.Post-implantation performance in both hearing sensitivity and speech recognition was assessed in different sessions.Aided hearing thresholds were tested by behavioral audiometry.Mandarin Early Speech Perception Test (MESP),Meaningful Auditory Integration Scale (MAIS),category of auditory performance (CAP) and Speech Intelligibility Rating (SIR) were used to assess the benefits in auditory skills or speech recognition the boy obtained from CI.The tests were administered before surgery and at 3 months and 7 months after opening.Results The boy demonstrated improved auditory sensitivity by using CI.Concerning speech recognition and communication,both speech audiometry and questionnaires showed an obvious benefit from CI.Conclusions CI has worked efficiently in this ANSD boy.But because of limited understanding of ANSD and rehabilitation effect by cochlear implantation in this condition,the clinical decision to implant should be cautious and only after a thorough evaluation.Meanwhile,well controlled and long term studies are needed to confirm the efficacy of cochlear implantation in patients with ANSD.展开更多
Objective: Congenital auditory neuropathy(AN) affects hearing and speech development. The degree of hearing difficulty in congenital AN varies as a function of pathology at the inner ear hair cell(IHC) synapses or the...Objective: Congenital auditory neuropathy(AN) affects hearing and speech development. The degree of hearing difficulty in congenital AN varies as a function of pathology at the inner ear hair cell(IHC) synapses or the auditory nerve. We report a case of a Chinese girl with AN revealed by OTOF(otoferlin) gene mutation analysis who had only a mild hearing loss.Patient: A 13-year-old Chinese girl was diagnosed as having congenital AN on the basis of OTOF gene mutation analysis. She manifest a mild sensorineural hearing loss with 50% maximum monosyllable speech discrimination rate, normal DPOAEs(distortion product otoacoustic emissions) beyond ambient noise levels, only SPs(summating potentials) evoked during ECoG(electrocochleography) and absent ABRs(auditory evoked brainstem responses) bilaterally to clicks presented at 100 d Bn HL. She was able to effectively communicate with others by speech reading owing to her mild hearing loss. Moreover, bilateral hearing aids helped her to communicate.Conclusions: Our patient was demonstrated to have a mutation on the OTOF gene. Nevertheless, she was able to communicate using auditory visual speech reading in spite of a mild auditory threshold elevation probably due to partial pathology at the IHC synapses or in the auditory nerve.展开更多
Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on ...Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on sound wave trans-mission.This method employs the artificial head technique, in which the head related transfer function was taken into account tothe outer ear simulation phase.First, a bionic artificial head was designed as the outer ear model with considering the outersound field in view of theory and physical explanations.Then the auditory peripheral simulation model was built, which mimicsthe physiological functions of the human hearing, simulating the acoustic signal transfer process and conversion mechanismsfrom the free field to the peripheral auditory system.Finally, performance comparison was made between the proposed SQOEmethod and ArtemiS software, and the verifications of subjective and objective related analysis were made.Results show thatthe proposed method was economical, simple, and with good evaluation quality.展开更多
Squamous papillomas(SPs) are common benign neoplastic lesions, usually affecting the skin, oral mucosa, upper aerodigestive tract and genital organs. However, SPs of the external auditory canal(EAC) are rarely reporte...Squamous papillomas(SPs) are common benign neoplastic lesions, usually affecting the skin, oral mucosa, upper aerodigestive tract and genital organs. However, SPs of the external auditory canal(EAC) are rarely reported in the English literature. In this report, we present a 19-year-old female with left EAC SP. The etiology, natural course, diagnosis and management of this disease are discussed, with a brief review of the literature.展开更多
基金The author received the funding from Sichuan Natural Science Foundation(2022NSFSC1892).
文摘The deployment of vehicle micro-motors has witnessed an expansion owing to the progression in electrification and intelligent technologies.However,some micro-motors may exhibit design deficiencies,component wear,assembly errors,and other imperfections that may arise during the design or manufacturing phases.Conse-quently,these micro-motors might generate anomalous noises during their operation,consequently exerting a substantial adverse influence on the overall comfort of drivers and passengers.Automobile micro-motors exhibit a diverse array of structural variations,consequently leading to the manifestation of a multitude of distinctive auditory irregularities.To address the identification of diverse forms of abnormal noise,this research presents a novel approach rooted in the utilization of vibro-acoustic fusion-convolutional neural network(VAF-CNN).This method entails the deployment of distinct network branches,each serving to capture disparate features from the multi-sensor data,all the while considering the auditory perception traits inherent in the human auditory sys-tem.The intermediary layer integrates the concept of adaptive weighting of multi-sensor features,thus affording a calibration mechanism for the features hailing from multiple sensors,thereby enabling a further refinement of features within the branch network.For optimal model efficacy,a feature fusion mechanism is implemented in the concluding layer.To substantiate the efficacy of the proposed approach,this paper initially employs an augmented data methodology inspired by modified SpecAugment,applied to the dataset of abnormal noise sam-ples,encompassing scenarios both with and without in-vehicle interior noise.This serves to mitigate the issue of limited sample availability.Subsequent comparative evaluations are executed,contrasting the performance of the model founded upon single-sensor data against other feature fusion models reliant on multi-sensor data.The experimental results substantiate that the suggested methodology yields heightened recognition accuracy and greater resilience against interference.Moreover,it holds notable practical significance in the engineering domain,as it furnishes valuable support for the targeted management of noise emanating from vehicle micro-motors.
文摘BACKGROUND Stapes ankylosis is a rare cause of conductive hearing loss,and stapes suprastructure fixation is extremely rare with fewer than 30 reported cases.Patients usually visit the clinic with non-progressive conductive hearing loss that typically began in the early years of life.CASE SUMMARY Herein,we report a case of a 37-year-old female with an isolated stapedial suprastructure fixation.The patient presented with unusual fluctuating auditory symptoms of tinnitus,ear fullness and mixed hearing loss.Pre-operative temporal bone computed tomography findings and operative findings revealed an isolated stapedial suprastructure fixation with monopod stapes caused by elongated pyramidal eminence.The hearing threshold recovered completely,and fluctuating auditory symptoms disappeared after the surgery.CONCLUSION This is the first report of stapedial suprastructure fixation with fluctuating auditory symptoms.Successful results are expected with surgical treatment.
基金supported by National Natural Science Foundation of China (31772464)Youth Innovation Promotion Association CAS (2012274)。
文摘In anurans, calling behaviour is strongly seasonal and circadian. Previous studies have revealed that a uditory sensitivity in frogs exhibits seasonal plasticity, and electroencephalographic signals exhibit highly correlated circadian patterns;of which, the circadian rhythm remains unknown. In this study,the circadian rhythm and intersexual differences of auditory sensitivity were tested in the Emei music frog(Nidirana daunchina). This was achieved by comparing thresholds and latencies of auditory brainstem responses(ABRs) evoked by tones and clicks stimuli between male and female frogs during the day and at night,respectively. Our results revealed that both auditory thresholds and latencies had no differences between day and night except the la tencies in 3.5–4.0 kHz frequencies. However, the thresholds of tone pip evoked ABRs differed significantly between male and female frogs from 2.5 to 5.0 kHz. This demonstrated that the auditory sensitivity of Emei music frogs exhibits sexual dimorphism at high frequencies, with female frogs exhibiting greater auditory sensitivity than that of male frogs. Simultaneously, the power spectra of male advertisement calls are matched well with the frequency range of auditory sensitivity in male and female frogs,which supports the matched filter hypothesis. Our study enhances the understanding of circadian plasticity and sexual dimorphism of auditory sensitivity in frogs.
文摘Transcranial electrical stimulation(tES)is a non-invasive nerve stimulation technique that modulates changes in neural activities in cerebral cortex through a weak current of specific intensity(and frequency).It has become a valuable tool for the study of human behavior and cognitive neurophysiological processes.As a brain stimulation technology with broad development prospects,it is not mature enough in the field of human auditory research.However,the research on tES has obtained preliminary results in regulating motor ability.This article mainly introduces the effects of tES and auditory steady state response on auditory,and the applications of tES in auditory diseases.By summarizing and discussing tES during auditory processing as comprehensively as possible,the potential application value of tES in the treatment of auditory diseases could be illustrated.
文摘Objective:The effect of long term auditory deprivation on Cortical Auditory Evoked Potentials(CAEPs)especially in human models is not well explored.Hence,the current study was aimed to investigate the effects of long-term auditory deprivation and stimulability of auditory cortex in non habilitated congenitally deaf adolescents and adults using CAEPs.Methods and Results:A total of 27 non-habilitated congenitally deaf adolescents/adults with age and gender matched normal hearing adolescents/adults participated in the study.The congenitally deaf group was fitted with high gain hearing aids(first fit).Further,the CAEPs were recorded.The obtained CAEP components were assessed for group effect,source and topographical differences.The between group analysis for CAEP responses showed a significant difference only for P2 latency and amplitude.The source analysis revealed that,in the normal hearing group for CAEPs,the sources were within the temporal regions.However,in the congenitally deaf group,along with the temporal cortex,the bilateral prefrontal cortex also was activated.Conclusion:The findings revealed that it is possible to stimulate and evoke a matured CAEP response from a long deprived auditory system with adequate acoustic stimulation.The presence of CAEP responses is indicative of the functionality of the innate auditory pathway and the crossmodal plasticity in long auditory deprived individuals.
文摘The amplitudes and latencies of auditory brainstem evoked response(ABR)were recorded at both high(50/s)and low(10/s)click rates as sound stimuli before andafter the guinea pigs were exposed to variant intensity noise.The maximum amplitude ofwave V increased significantly,but those of wave Ⅰ,Ⅲ,and Ⅳ decreased significantly afterexposure to 110 dB noise for 20 or 30 min.The wave Ⅴ latency recorded at 50/s clickrate was shorter in every group after exposure.The changes of wave V latency recordedat 10/s click rate were complex,it was shorter after exposure to 95 dB or 105 dB for 10min;no change was found after exposure to 110 dB for 10 min,but it was longer initiallyand then became shorter after exposure to 110 dB noise for 30 min.The difference valueof wave V latency from 10/s to 50/s was negatively correlated with the noise intensityand exposure time.The more intense noise stimuli and the longer time,the less the differ-ence value became.The results indicate that the auditory bralnstem center was affectedby intense noise,and it is helpful to use difference value of wave V latency to analysis thefunction of brainstem center after exposure to noise.
文摘Objectives To investigate changes in evoked potentials and structure of the guinea pig cochleae during whole cochlear perfusion with glutamate. Methods CM, CAP, DPOAE, and ABR were recorded as indicators of cochlear functions during whole cochlear perfusion. The morphology of the cochlea was studied via transmission electron microscopy. Results There were no significant changes in DPOAE amplitude before and after glutamate perfusion. CM I/O function remained nonlinear during perfusion. ABR latencies were delayed following glutamate perfusion. The average CAP threshold was elevated 35 dB SPL following glutamate perfusion.. The OHCs appeared normal, but the IHCs and afferent dendrites showed cytoplasmic blebs after glutamate perfusion. Conclusions While being a primary amino acid neurotransmitter at the synapses between hair cells and spiral ganglion neurons, excessive glutamate is neurotoxic and can destroy IHCs and spiral ganglion neurons. The technique used in this study can also be used to build an animal model of auditory neuropathy.
基金supported by grants from the Science and Technology Innovation Nursery Foundation of PLA General Hospital(12KMM29)the military medical metrology research project(2012-JL1-028)+1 种基金Clinical Research Supporting Foundation of PLA General Hospital(2012FC-TSYS-3056)the Military Medical and Sanitation Research Project(11BJZ33)
文摘Objective To analyze the characteristics of auditory brainstem response(ABR) in presbycusis patients elder than 90 years. Methods Fourteen presbycusis patients elder than 90 years(presbycusis group, 91.1.4±1.3 years, 26 ears) and 9 normal-hearing young adults(control group, 22.7±1.2 years, 18 ears) participated in the study. Alternative click-evoked ABRs were recorded in both groups. The peak latency(PL) of peak I,Ⅲ, and V, and the inter-peak latency(IPI) of I-Ⅲ, Ⅲ-V, and I-V were compared between groups. Results In elder presbycusis patients, the occurrence rate of peak I and Ⅲ were both 76.9%, and that of peak V was84.6%. In presbycusis group, the peak latencies of I, Ⅲ, V were significantly longer than that of control group(P<0.001). There was no significant difference between groups in the IPI of peak I-I Ⅲ(P=0.298,peak Ⅲ-V(P=0.254) and peak I-V(P=0.364). Conclusions Auditory brainstem responses in presbycusis patients elder than 90 years showed worse wave
基金supported by Natural Science Foundation of China[grant numbers 81760188]Scientific Research Fund of Guangxi Provincial Education Department [grant numbers 2017KY0103 (02601217023C)]
文摘To characterize the patterns of ABR waves in tree shrews, we must understand the hearing sensitivity and auditory function of healthy adult tree shrews. Fifteen tree shrews(30 ears) were stimulated with clicks and tone-pips at 11 different frequencies from 1 to 60 kHz. The ABR waves were recorded and analyzed. The ABR consisted of five to seven positive waves in the first 10 ms after a click stimulus, and the average hearing threshold of component III was 27.86 ± 3.78 dB SPL. Wave III was the largest and most clear. The ABR threshold was related to the tone-pip sitmulus by a "U" shaped curve. The sensitive frequency was approximately 8 kHz in tree shrews. The latencies systematically decreased with increasing stimulus frequencies. The ABR amplitudes of wave III increased as the sound pressure level increased. All of these results provide an empirical basis for future studies of hearing diseases in tree shrews.
文摘Transcranial direct current stimulation(tDCS)has been reportedly beneficial for different neurodegenerative disorders.tDCS has been reported as a potential adjunctive or alternative treatment for auditory verbal hallucination(AVH).This study aims to review the effects of tDCS on AVH in patients with schizophrenia through combining the evidence from randomized clinical trials(RCTs).The databases of PsycINFO(2000–2019),PubMed(2000–2019),EMBASE(2000–2019),CINAHL(2000–2019),Web of Science(2000–2019),and Scopus(2000–2019)were systematically searched.The clinical trials with RCT design were selected for final analysis.A total of nine RCTs were eligible and included in the review.Nine RCTs were included in the final analysis.Among them,six RCTs reported a significant reduction of AVH after repeated sessions of tDCS,whereas three RCTs did not show any advantage of active tDCS over sham tDCS.The current studies showed an overall decrease of approximately 28%of AVH after active tDCS and 10%after sham tDCS.The tDCS protocols targeting the sensorimotor frontal-parietal network showed greater treatment effects compared with the protocols targeting other regions.In this regard,cathodal tDCS over the left temporoparietal area showed inhibitory effects on AVHs.The most effective tDCS protocol on AVHs was twice-daily sessions(2 mA,20-minute duration)over 5 consecutive days(10 sessions)with the anode over the left dorsolateral prefrontal cortex and the cathode over the left temporal area.Some patient-specific and diseasespecific factors such as young age,nonsmoking status,and higher frequencies of AVHs seemed to be the predictors of treatment response.Taken together,the results of tDCS as an alternative treatment option for AVH show controversy among current literatures,since not all studies were positive.However,the studies targeting the same site of the brain showed that the tDCS could be a promising treatment option to reduce AVH.Further RCTs,with larger sample sizes,should be conducted to reach a conclusion on the efficacy of tDCS for AVH and to develop an effective therapeutic protocol for clinical setting.
基金supported by the Beijing Science and Technology Project Foundation of China, No.Z181100001718066(to HTL)。
文摘The current randomized controlled trial was performed at the China Rehabilitation Science Institute, China to test the hypothesis that musical auditory stimulation has positive effects on the autonomic nervous system of patients with disorder of consciousness.Although past studies have recommended that patients with disorder of consciousness listen to patient-preferred music, this practice is not universally accepted by researchers.Twenty patients with severe disorder of consciousness listened to either therapist-selected(n = 10, 6 males and 4 females;43.33 ± 18.76 years old) or patient-preferred(n = 10, 5 males and 5 females, 48.83 ± 18.79 years old) musical therapy, 30 minutes/day, 5 times/week for 6 weeks.The results showed no obvious differences in heart rate variability-related parameters including heart rate, standard deviation of normal-to-normal R-R intervals, and the root-mean-square of successive heartbeat interval differences of successive heartbeat intervals between the two groups of patients.However, percentage of differences exceeding 50 ms between adjacent normal number of intervals, low-frequency power/high-frequency power, high-frequency power norm, low-frequency power norm, and total power were higher in patients receiving therapist-selected music than in patients receiving their own preferred music.In contrast, this relationship was reversed for the high-frequency power and very-low-frequency band.These results suggest that compared with preferred musical stimulation, therapist-selected musical stimulation resulted in higher interactive activity of the autonomic nervous system.Therefore, therapist-selected musical stimulation should be used to arouse the autonomic nervous system of patients with disorder of consciousness.This study was approved by the Institutional Ethics Committee of China Rehabilitation Research Center, China(approval No.2018-022-1) on March 12, 2018 and registered with the Chinese Clinical Trial Registry(registration number Chi CTR1800017809) on August 15, 2018.
文摘Acquired atresia of the external auditory canal(EAC)is a rare cause of conductive hearing loss.It has been traditionally classified into 4 categories:traumatic,post-operative,neoplastic and inflammatory.Post-inflammatory acquired auditory canal atresia is thought to be the result of chronic and repetitive infectious bouts affecting the auditory canal.Nevertheless,the underlying pathophysiology of this disorder is yet to be fully elucidated.Current data fail to clearly state the impact that certain underlying systemic disorders may have on the EAC.The possible association to metabolic disturbances such as iron deficiency is also emphasized.In the light of these findings,this analysis can be used to improve the classification of this entity thereby standardizing the assessment of therapeutic approaches.
文摘AIM To provide an updated of recent findings about efficacy of cognitive-behavior therapy(CBT) in reduction of command hallucinations.METHODS Pub Med/MEDLINE,Cochrane Library,the Cumulative Index to Nursing and Allied Health Literature,PsycI NFO,Clinical Trial.gov searches were performed using the keywords "hallucinations","behavioural therapy" and " cognitive therapy" in order to identify relevant articles published during the years of 2011 to 2016.No language limits were used.Studies conducted within control group,reviews,editorials,were excluded.Data on efficacy,acceptability and tolerability were extracted by three authors independently.Disagreements were resolved in a consensus meeting or by another reviewer.RESULTS A total of eight articles were eligible for inclusion.Two are randomized clinical trials(RCTs) and six are observational studies.The two RCTs included showed a greater efficacy of CBT compared to standard care on auditory hallucinations(AHs).Nevertheless,they considered different CBT models,particularly Treatment of Resistant Command Hallucinations and Cognitive Therapy for Command Hallucinations.As regards non RCT-studies,all papers included showed reduction on frequency and severity of AHs and distress related to them.However,the lack of content details within non-RCTs studies decreased their comparability.In terms of predictive variables,our findings show that negative symptoms at baseline appeared to be the strongest predictor of the treatment efficacy.Indeed,negative symptoms showed a significant negative correlation on outcome.CONCLUSION Although more conclusive studies are still needed,we found some preliminary evidence for the efficacy of CBT in the treatment of command hallucinations.
基金supported by National Science Foundation of China (Grant 30600125)National Science Foundation Hebei Province (Grant C2011206036)
文摘The development and plasticity of central auditory system can be influenced by the change of peripheral neuronal activity. However, the molecular mechanism participating in the process remains elusive. Brain-derived neurotrophic factor(BDNF) binding with its functional receptor tropomyosin receptor kinase B(TrkB) has multiple effects on neurons. Here we used a rat model of auditory deprivation by bilateral cochlear ablation, to investigate the changes in expression of BDNF and Trk B in the auditory cortex after auditory deprivation that occurred during the critical period for the development of central auditory system. Reverse transcription-quantitative polymerase chain reaction(RTqPCR) and immunohistochemistry methods were adopted to detect the m RNA and protein expression levels of BDNF and TrkB in the auditory cortex at 2, 4, 6 and 8 weeks after surgery, respectively. The change in the expression of BDNF and TrkB mRNAs and proteins followed similar trend. In the bilateral cochlear ablation groups, the BDNF-TrkB expression level initially decreased at 2 weeks but increased at 4 weeks followed by the reduction at 6 and 8 weeks after cochlear removal, as compared to the age-matched sham control groups. In conclusion, the BDNF-TrkB signaling is involved in the plasticity of auditory cortex in an activity-dependent manner.
基金Supported by European Research Council Advanced Grant,No.#249516Research Council of Norway FRIBIOMED Grant,No.807696SFF Grant,No.222373
文摘In this invited review I provide a selective overview of recent research on brain mechanisms and cognitive processes involved in auditory hallucinations. The review is focused on research carried out in the "VOICE" ERC Advanced Grant Project, funded by the European Research Council, but I also review and discuss the literature in general. Auditory hallucinations are suggested to be perceptual phenomena, with a neuronal origin in the speech perception areas in the temporal lobe. The phenomenology of auditory hallucinations is conceptualized along three domains, or dimensions; a perceptual dimension, experienced as someone speaking to the patient; a cognitive dimension, experienced as an inability to inhibit, or ignore the voices, and an emotional dimension, experienced as the "voices" having primarily a negative, or sinister, emotional tone. I will review cognitive, imaging, and neurochemistry data related to these dimensions, primarily the first two. The reviewed data are summarized in a model that sees auditory hallucinations as initiated from temporal lobe neuronal hyper-activation that draws attentional focus inward, and which is not inhibited due to frontal lobe hypo-activation. It is further suggested that this is maintained through abnormal glutamate and possibly gamma-amino-butyric-acid transmitter mediation, which could point towards new pathways for pharmacological treatment. A final section discusses new methods of acquiring quantitative data on the phenomenology and subjective experience of auditory hallucination that goes beyond standard interview questionnaires, by suggesting an iP hone/iP od app.
基金'This study was supported by grants from the National 973 Program of China(No.201 lCB707805)the National Natural Science Foundation of China(No.91132301)the Natural Science Foundation of Hubei Province(No.2014CFB732).
文摘Auditory verbal hallucination(AVH)is emphasized as a pathological hallmark of schizophrenia.Neuroimaging studies provide evidence linking AVH to overlapping functional abnormalities in distributed networks.However,no clear conclusion has still been reached.This study aimed to further explore the brain activity of patients with schizophrenia having AVH from both local activity(LA)and functional connectivity(FC)insights,while excluding confounding factors from other positive symptoms.A total of 42 patients with AVH(AVH patients group,APG),26 without AVH(non-AVH patients group,NPG),and 82 normal controls(NC)underwent resting-state functional magnetic resonance imaging(fMRI).LA measures,including regional homogeneity(ReHo)and fractional amplitude of low-frequency fluctuations(fALFF),and FC measures were evaluated to understand the neuroimaging mechanism of AVH.APG showed increased ReHo and fALFF in the bilateral putamen(Put)compared with NPG and NC.FC analysis(using bilateral putamen as seeds)revealed that all patients showed abnormal FC of multiple resting state network regions,including the anterior and post cingulate cortex,middle frontal gyrus,inferior parietal gyrus,and left angular gyrus.Interestingly,APG showed significantly decreased FC of insula extending to the superior temporal gyrus and inferior frontal gyrus compared with NPG and NC.The present findings suggested a significant correlation of abnormal LA and dysfunctional putamen-auditory cortical connectivity with the neuropathological mechanism of AVH,providing evidence for the functional disconnection hypothesis of schizophrenia.
基金supported by grants from the National Basic Research Program of China(973Program)(#2012CB9679002011CBA01000)National Hi-Tech Research and Development Program of China(863Program)(#2007AA02Z150)to SMYthe National Natural Science Foundation of China(NSFC)(#30730040)to Yang Shi-ming
文摘Objective To report outcomes of cochlear implantation (CI) in a child with auditory neuropathy spectrum disorder (ANSD) and to provide preliminary clinical evidence of the efficacy of CI in ANSD patients.Methods A 4-year-old boy with diagnosed auditory neuropathy spectrum disorder (ANSD) received implantation of a Nucleus CI24R after an unsatisfactory trial of amplification.Post-implantation performance in both hearing sensitivity and speech recognition was assessed in different sessions.Aided hearing thresholds were tested by behavioral audiometry.Mandarin Early Speech Perception Test (MESP),Meaningful Auditory Integration Scale (MAIS),category of auditory performance (CAP) and Speech Intelligibility Rating (SIR) were used to assess the benefits in auditory skills or speech recognition the boy obtained from CI.The tests were administered before surgery and at 3 months and 7 months after opening.Results The boy demonstrated improved auditory sensitivity by using CI.Concerning speech recognition and communication,both speech audiometry and questionnaires showed an obvious benefit from CI.Conclusions CI has worked efficiently in this ANSD boy.But because of limited understanding of ANSD and rehabilitation effect by cochlear implantation in this condition,the clinical decision to implant should be cautious and only after a thorough evaluation.Meanwhile,well controlled and long term studies are needed to confirm the efficacy of cochlear implantation in patients with ANSD.
文摘Objective: Congenital auditory neuropathy(AN) affects hearing and speech development. The degree of hearing difficulty in congenital AN varies as a function of pathology at the inner ear hair cell(IHC) synapses or the auditory nerve. We report a case of a Chinese girl with AN revealed by OTOF(otoferlin) gene mutation analysis who had only a mild hearing loss.Patient: A 13-year-old Chinese girl was diagnosed as having congenital AN on the basis of OTOF gene mutation analysis. She manifest a mild sensorineural hearing loss with 50% maximum monosyllable speech discrimination rate, normal DPOAEs(distortion product otoacoustic emissions) beyond ambient noise levels, only SPs(summating potentials) evoked during ECoG(electrocochleography) and absent ABRs(auditory evoked brainstem responses) bilaterally to clicks presented at 100 d Bn HL. She was able to effectively communicate with others by speech reading owing to her mild hearing loss. Moreover, bilateral hearing aids helped her to communicate.Conclusions: Our patient was demonstrated to have a mutation on the OTOF gene. Nevertheless, she was able to communicate using auditory visual speech reading in spite of a mild auditory threshold elevation probably due to partial pathology at the IHC synapses or in the auditory nerve.
文摘Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on sound wave trans-mission.This method employs the artificial head technique, in which the head related transfer function was taken into account tothe outer ear simulation phase.First, a bionic artificial head was designed as the outer ear model with considering the outersound field in view of theory and physical explanations.Then the auditory peripheral simulation model was built, which mimicsthe physiological functions of the human hearing, simulating the acoustic signal transfer process and conversion mechanismsfrom the free field to the peripheral auditory system.Finally, performance comparison was made between the proposed SQOEmethod and ArtemiS software, and the verifications of subjective and objective related analysis were made.Results show thatthe proposed method was economical, simple, and with good evaluation quality.
文摘Squamous papillomas(SPs) are common benign neoplastic lesions, usually affecting the skin, oral mucosa, upper aerodigestive tract and genital organs. However, SPs of the external auditory canal(EAC) are rarely reported in the English literature. In this report, we present a 19-year-old female with left EAC SP. The etiology, natural course, diagnosis and management of this disease are discussed, with a brief review of the literature.
