年龄相关性听力损失与认知功能障碍的关联机制

年龄相关性听力损失以双侧对称性和渐进性的听力损失为特征,高频区域的听力损失更为明显。横断面和纵向研究均表明,年龄相关性听力损失与认知功能障碍之间存在关联性。听力损失对痴呆的可改变风险因素高于其他已知的因素,包括抑郁、社会隔离、吸烟、高血压等,使其成为认知功能障碍和痴呆预防策略中新的目标。听力损失和认知功能障碍的关联机制可分为因果机制假说和共同病因假说两个类别。其中因果机制包括信息退化、听觉剥夺和社会孤立三种假说,均可解释为听力损失通过中间变量造成认知功能下降。共同病因假说指存在同时造成听力损失和认知功能障碍的混杂因素。当前针对老年人群进行的认知和听力损失的研究在评估方法上存在一些限制,未来应结合纯音测听、言语测试以及中枢听觉测试等技术开展研究。听觉以外的感觉功能,如视觉、嗅觉和本体感觉,也可能与认知功能障碍有关,应结合不同感觉功能障碍开展认知功能障碍的关联研究。     

噪声性听力损失易感性相关基因的研究进展

人们每天都接受到来自周围环境的不同声音,这些声音都是以声波形式到达内耳,转换为电信号,最终由听神经传入大脑,正常情况下不会对听力造成损害,但当声音强度过高和/或持续时间过长时,就可能会对听力造成损害,引起噪声性听力损失(noise-induced hearing loss, NIHL).研究表明,长期或反复暴露于强度高于85 dB A的声刺激环境,可导致内耳精细结构破坏,主要表现为感觉上皮(包括内毛细胞和外毛细胞)和听觉神经元受损并最终死亡.噪声暴露后,听力损失可能即刻发生,也可缓慢持续进展,可以是暂时性或永久性的,可能累及单耳或双耳.目前,NIHL是除老年性听力损失以外最常见的感音神经性聋,美国疾病控制中心(Centers for Disease Control, CDC)2010年的数据[1]显示,在20~69岁的美国人群中,约有2 600万人患有NIHL,患病率达15%;12~19岁美国青少年的听力损失可能有16%由噪声导致.因此,NIHL威胁着各年龄段人群的听觉健康.     

光学遗传用于听力恢复的研究进展北大核心CSCD

听力损失(Hearing loss,HL)是最常见的感觉缺陷,感音神经性听力损失(sensorineural hearing loss,SNHL)是耳蜗功能障碍导致的最常见的症状,目前尚无有效的因果疗法。助听器和电子耳蜗(electric Cochlear implants,eCIs)仍是听力康复的主要选择。eCIs构成一个脑机接口,通过电刺激听觉神经将患者与听觉场景重新联结起来,目前被认为是最成功的神经假体。但eCIs内的电流广泛传播,这将限制听力质量。而光能更好地限制在空间中,光学人工耳蜗(optical cochlear implant,oCIs)应用的听觉神经的光学遗传刺激有望能使人工声音编码的分辨率更高,进而为听力恢复提供另一种更有效方法。本文主要围绕听力恢复的现状和局限性、oCIs的生物医学和光电发展现状等方面展开阐述。     

听力损失与听觉中枢可塑性

听力损失不仅可以导致听觉中枢功能的重组,而且其结构形态、物质代谢、神经递质及受体,相关基因及酶等也发生了变化.本文综述了听觉系统可塑性的临床和动物实验研究,对这些变化的发现将对包括听觉中枢在内的中枢神经系统功能和听觉机制的认识具有重要意义.     

老年性听力损失研究进展及应对策略

近年来,人口老龄化已成为国际社会共同面对的难题,据估计到2050 年,全球 60 岁以上的人口比例将高达 21.1％,老龄人口总数将超过 20 亿[1].随着年龄增长,老年人的各种感觉功能减退,其中以听觉功能减退最为明显.老年性听力损失亦称为年龄相关性听力损失,是继高血压和关节炎后老年人所面临的第三大健康问题.老年性听...     

孤独症儿童听力的初步探讨

孤独症是一种发生在低龄儿童严重的精神疾病，患儿有听力和言语发育障碍。其对声音的异常反应，表现为听觉减退和听觉敏感两个相互矛盾的方面。通过对９例１８耳孤独症患儿的ＡＢＲ检查，证实患儿有听力，且基本正常。但患儿的听觉敏感问题由于患儿的不合作，尚不能被证实，有待进一步探讨。     

中国第二次残疾人抽样调查听力残疾标准介绍

1听力残疾定义及分级1.1听力残疾的定义听力残疾,是指人由于各种原因导致双耳不同程度的永久性听力障碍,听不到或听不清周围环境声及言语声,以致影响日常生活和社会参与。1.2听力残疾的分级听力残疾一级听觉系统的结构和功能方面极重度损伤,较好耳平均听力损失≥91dB HL,在无助听设备帮助下,不能依靠听觉进行言语交流,在理解和交流等活动上极度受限,在参与社会生活方面存在极严重障碍。听力残疾二级听觉系统的结构和功能重度损伤,较好耳平均听力损失在81~90dB HL之间,在无助听设备帮助下,在理解和交流等活动上重度受限,在参与社会生活方…     

听力正常的耳鸣患者临床听力学诊断

耳鸣是常见临床症状,听力正常的耳鸣患者亦不少见.近年来随着各种客观听力学检测方法在临床中的推广应用,人们逐渐认识到听力正常并不意味着听觉系统的正常.临床利用听力学检测方法研究听力正常的耳鸣患者病理生理机制、病变部位的确定及治疗效果的评估等成为了热点.本文对近年来国内外听力正常的耳鸣患者相关临床听力学诊断研究进展做一综述.     

听力损失及其对听觉感知的影响— 基于系统方法的研究进展

本文从系统研究的角度出发,总结了不同类型听力损失的病因学、组织病理学、心理物理学和听力学的表现及其对听觉感知功能的影响,为进一步理解听力损失的机制及听力耳聋患者的治疗提供了不同的视角.     

儿童听力筛查的必要性

儿童时期尤其是婴儿期,即使听觉输入仅有轻微改变也会导致明显的言语发育迟缓 ,进而对其后期的学习和社会交流产生不良影响[1 ] .随着新生儿听力筛查在全球范围的普遍实施 ,先天性听力损失和早期获得性听力损失的确诊时间大大提前 ,为后期的干预和康复争取了时间.然而与新生儿听力损失的发病率(0.1% )相比 ,儿童听力损失的发病率却明显增高.     

Effect of hearing aids on hearing

We examined 114 patients aged 10 to 91 years with different kinds of hearing aids fitted in one ear only, the unaided ear acting as a control. They were re-examined several times during a period of follow-up from 1 to 9 years comparing the relative change in hearing due to hearing aid usage with various degrees of amplification of the aid. We compared the degree of hearing loss in the aided and unaided ear looking for evidence of a possible change in hearing related to the frequency of hearing aid usage in hours per day and in years, the maximum power output (MPO) and the gain of the aid. According to our findings there is no change in hearing between the aided and the unaided ear at the alpha = 0.05 probability level at least for 8 years. There is no effect of the long-term amplification of the hearing aid on deterioration of hearing comparing the aided ear and the unaided ear, but with high MPO of the aid, the patient should be followed up more frequently than with low MPO amplification.     

Rehabilitation of patients with hearing disorders using hearing aids and tactical hearing measures

After a brief summary of the problems of rehabilitation of hearing-impaired subjects, the optimal conditions for rehabilitation with hearing aids are presented: a) The right timing is crucial. b) Optimal provision of hearing aids must be carried out in close co-operation between the patient, the hearing aid technician and the otolaryngologist. c) Easy handling of the hearing aid and the use of attachments must be guaranteed. d) The hearing-impaired person must be fully informed as to the extent and type of hearing loss. He/she must accept the affliction and know about the possibilities of rehabilitation. The patient's motivation is a pre-requisite for all further steps. e) The patients must learn tactical measures to make optimal use of their hearing ability in relation to their environment. Hearing tactics consist of hearing training and a change in the attitude of the hearing-impaired patients themselves and their attitude towards their surroundings.     

The influence of hearing loss on directional hearing

Fifty patients with cochlear hearing loss were tested with phase audiometry. Thirty-three of the patients had unilateral hearing loss at 500 Hz and 17 bilateral, symmetrical hearing loss at 500 Hz. Those patients who had slight hearing loss (less than 40 dB HL) had as a rule normal directional hearing. Those who had hearing loss exceeding 40 dB HL at 500 Hz usually had abnormal directional hearing. The sound lateralization ability was independent of whether the hearing loss was unilateral or bilateral.     

Evaluation of hearing improvement due to hearing aids

A method to assess the hearing improvement due to hearing aids is described. This method has been used routinely at a local hospital for 2 years on 200 patients. This method is based on the assessment of the speech reception threshold for sentences ("Marburger Satztest") in silence and in various noise levels (speech simulating noise). The following were used for the assessment of the hearing aid: the improvement of the speech reception threshold in silence with or without a hearing aid, the maximum tolerable noise level (i.e. the noise level at which everyday speech becomes subliminal for patients with hearing aids) and the noise level at which the speech reception threshold with the hearing aid is worse than without.     

极重度聋及其听力康复技术

根据世界卫生组织(WHO-1997)的听力障碍分级标准,极重度聋是指好耳侧500Hz、1000Hz、2000Hz、4000Hz处的纯音听阈均值大于80dB HL。较我国1987年第一次残疾人口调查时采用的听力残疾分级标准有较大改变,一是增加了测试频率4000Hz,二是听阈标准由90dB HL降低至80dB HL。2006年,我国第二次全国残疾人口抽样调查采用了新的听力残疾分级标准,既考虑到我国原先使用的标准又做到了与国际接轨。我国新标准将世界卫生组织标准中的极重度聋细分为听力残疾一级和听力残疾二级,听阈在81～90dB HL为二级,在90dB HL以上为一级。严重的听力障碍…