聴覚過敏

聴覚過敏症は、音（痛みを含む）に対する過敏性の増加^{[ 1 ]}と環境騒音に対する耐性の低下です。聴覚過敏症の定義は大きく異なる場合があり、多くの場合、鐙骨、鐙骨筋、または鼓膜張筋の損傷または機能不全に関連しています。これは、音量、痛み（ノクサクシスとも呼ばれる）、不快感、恐怖の4つのサブタイプに分類されることがよくあります。 ^{[ 2 ] [ 3 ]}これは、非常に衰弱させる聴覚障害になる可能性があります。^{[ 4 ]}

原因や危険因子は様々で、最も一般的なのは騒音への曝露です。^{[ 2 ]}耳鳴りと同時に起こることもよくあります。^{[ 2 ]}文献で提案されているメカニズムには、脳、内耳、または中耳の機能障害が含まれます。^{[ 5 ] [ 6 ] [ 7 ] [ 8 ] [ 9 ] [ 10 ]}

聴覚過敏の有病率についてはほとんど知られていないが、これは用語の定義にばらつきがあることが一因である。^{[ 2 ] [ 11 ]}報告されている有病率の推定値は大きく異なり、確固たる疫学的データを得るにはさらなる研究が必要である。^{[ 12 ]}

聴覚過敏の症状には、ほとんどの人が影響を受けない音に対する音の大きさの知覚の増加（音量過敏）、痛み（不快感過敏/疼痛過敏/音誘発性耳痛）、不快感、および/または恐怖が含まれます。 ^{[ 13 ]}片耳または両耳に影響を及ぼします。^{[ 14 ]}患者の大多数は両側性の症状を経験しますが、多くの場合、片方の耳がもう一方の耳よりも影響を受けます。不快感過敏は、ミソフォニアと同義とみなされることがよくあります。恐怖過敏は、フォノフォビアと同義とみなされることがよくあります。多くの研究者は、聴覚過敏をより狭義に定義し、音量過敏と疼痛過敏のみを含めるようにしています。^{[ 14 ]}

聴覚過敏には耳鳴りが伴うこともある。^{[ 15 ]}耳鳴りの方が一般的で^{[ 16 ]}、そのメカニズムには重要な違いがある。^{[ 4 ]}

Hyperacusis can result in anxiety and stress. Avoidant behavior is often a response to prevent the effects of hyperacusis and this can include avoiding social situations.^[17]

聴覚過敏の最も一般的な原因は、過度に高いデシベル（音圧）レベルへの過剰な曝露であり、これは音響外傷を引き起こす可能性があります。^{[ 2 ]}聴覚過敏や耳の痛みなどの症状を引き起こす可能性のある音響ショックは、予期せぬ中程度から大きな騒音への曝露後にも発生する可能性があり、これは必ずしも永久的な蝸牛損傷につながるわけではありません。^{[ 8 ]}

影響を受けた人の中には、聴覚を司る細胞を損傷する可能性のある耳毒性薬の服用、ライム病、メニエール病、頭部外傷、または手術の結果として突然聴覚過敏を発症する人もいます。また、生まれつき音に敏感な人や、上側半規管裂開症候群を発症する人もいます。^{[ 36 ]}ベル麻痺は、関連する弛緩性麻痺が中耳の2つの小さな筋肉である鼓膜張筋とアブミ骨筋に影響を与えると、聴覚過敏を引き起こす可能性があります。^{[ 37 ]}アブミ骨筋の麻痺は、耳小骨の振動を減衰させるその機能を妨げ、影響を受けた側の音が異常に大きくなります。^{[ 38 ]}年齢も重要な要因となる可能性があり、若い患者ほど聴覚過敏が重度になる傾向があります。^{[ 12 ]}

最近、GJB2（Cx26）遺伝子変異を1コピー持つ人は、平均よりも聴覚が敏感で、過敏症に似ていることが発見されました。これらの人は、騒音による損傷のリスクが高いようです。^{[ 39 ]}

Some psychoactive drugs such as LSD, methaqualone, benzodiazepines, or phencyclidine can cause hyperacusis.^[12][40] An antibiotic, ciprofloxacin, has also been seen to be a cause, known as ciprofloxacin-related hyperacusis.^[41]Benzodiazepine withdrawal syndrome is also a possible cause.^[42][43]

Prevalence estimates for hyperacusis vary widely in the literature, and further epidemiological data is needed. No gender differences have yet been established among hyperacusis patients. Hyperacusis appears to be more severe in younger patients.^[12]

The basic diagnostic test is similar to a normal audiogram. The difference is that, in addition to the hearing threshold at each test frequency, the lowest uncomfortable sound level is also measured. This level is called loudness discomfort level (LDL) or uncomfortable loudness level (ULL). In patients with hyperacusis this level is often considerably lower than in normal subjects, and usually across most parts of the auditory spectrum.^[2][45] However, there is not a consensus regarding what constitutes a normal LDL. The relationship between LDL's and self-reported ability to tolerate sounds in everyday life in unclear.^[46]

In addition to self-report questionnaires, audiologists may employ a variety of other techniques to evaluate auditory function in patients experiencing noise sensitivity. When conducting testing that involves the presentation of sounds, which may cause the patient discomfort or pain, it is vital to inform the patient of the volume and duration of sounds to be presented prior to testing. Care should be taken to begin with sounds of low volume, and volume should be increased gradually. The audiologist and patient should both be prepared to stop testing at any time, depending on the patient's symptoms.^[46]

There are currently no evidence-based guidelines regarding the treatment of patients with hyperacusis. The majority of audiologists report insufficient formal education in this area, likely due in part to the current lack of consensus in the literature regarding definitions and treatment of hyperacusis.^[47] Dr. Kelly Jahn surveyed 32 patients^[48] with severe pain hyperacusis and found that 95% of them had experienced a lack of empathy or support from doctors (20% somewhat agree and 75% strongly agree, with a 5% non response rate).^[49]

The Hyperacusis Memorial Wall of Remembrance is dedicated to hyperacusis patients and their stories.^[64]

• Musician Jason DiEmilio, who recorded under the name Azusa Plane, had hyperacusis and ultimately went on to die by suicide due in part to his sensitivity to noise.^[65]
• Dietrich Hectors, a hyperacusis sufferer in Belgium, took his life in 2009, after years of struggling with catastrophic hyperacusis and tinnitus.^[66][67] A local government in Belgium made a short film based on his life to warn others of the dangers of hyperacusis and tinnitus.^[68]
• Musician Stephin Merritt has monaural hyperacusis in his left ear, which influences the instrumentation of his band, The Magnetic Fields, leads him to wear earplugs during performances and to cover his affected ear during audience applause.^[69]
• ロシアの共産主義革命家、政治家、政治理論家であるウラジーミル・レーニンは、 1921年後半までに重病を患い、定期的な頭痛や不眠症など、聴覚過敏症と一致する可能性のある症状を呈していたと報告された。^{[ 70 ]}
• ジ・アントラーズのミュージシャン、ピーター・シルバーマンは、蝸牛水腫による聴覚過敏と耳鳴りを患い、症状が「管理可能なレベル」まで軽減するまで音楽活動を中断せざるを得なかった。^{[ 71 ]}
• レーシングドライバーのヴォルフガング・レイプは、レースキャリア中に何度か騒音による外傷を受けた後、重度の聴覚過敏症を発症した。^{[ 72 ]}
• ルートヴィヒ・ヴァン・ベートーヴェンは、難聴に加えて聴覚過敏症を患っていた可能性がある。彼は手紙の中で、「誰かが大声で叫ぶと、耐えられない。私の身に何が起こるかは神のみぞ知る」と書いている。^{[ 73 ]}
• イギリスの作家リンダ・ストラットマンは聴覚過敏症を患っており、音が「メスのように切り裂かれる」と報告している。^{[ 74 ] [ 75 ]}
• 日本人男性の大浜松造は聴覚過敏症を患っており、ピアノの音をめぐって近隣住民３人を殺害した。^{[ 76 ]}
• ロックバンドSuperchunkのベーシストであり、 Merge Recordsの共同創設者でもあるミュージシャンのローラ・バランセは、聴覚過敏症を患っており、その結果ツアー活動を中止した。^{[ 77 ]}

In the context of global hearing health initiatives, such as World Hearing Day promoted annually by the World Health Organisation (WHO), hyperacusis has been increasingly recognised as a relevant public health issue due to its impact on communication, daily functioning, and quality of life. Although public discourse on hearing health has traditionally focused on hearing loss, conditions involving decreased sound tolerance, including hyperacusis, are gaining attention as they can be equally disabling. This is particularly relevant in contemporary discussions of neurodevelopmental conditions, such as autism spectrum disorder (ASD), in which auditory hypersensitivity is often reported. Individuals with ASD often exhibit atypical sensory processing, and increased sensitivity to sound may manifest as distress, avoidance behaviours, or pain in response to everyday auditory stimuli. This auditory intolerance can significantly interfere with social participation, educational engagement, and therapeutic interventions, thereby compounding the communication challenges commonly associated with ASD.^[78]

Increased awareness of hyperacusis in hearing healthcare settings is aligned with broader efforts to promote early identification, prevention of hearing injury, and appropriate treatment of sound-related disorders throughout life. From a public health perspective, integrating hyperacusis into global hearing health initiatives highlights the need for multidisciplinary approaches involving audiology, speech therapy, neurology, and mental health services.^[79] This is particularly important given the growing recognition of differences in sensory processing in populations with neurodevelopmental disorders and the increasing prevalence of environmental noise exposure worldwide. Addressing hyperacusis within the scope of hearing health awareness campaigns can contribute to better recognition, reduced stigma, and the development of more inclusive clinical and environmental accommodations for affected individuals.

In this context, the 2026 World Hearing Day theme, "From communities to classrooms: hearing care for all children: Act now so that no child is left behind due to ear or hearing problems," highlights childhood hearing care as a global public health priority. Although the official campaign focuses on universal childhood ear and hearing care, this framework can support inclusive strategies that address auditory sensitivity and sound intolerance in diverse pediatric populations, including those with neurodevelopmental conditions such as autism spectrum disorder.^[80]

• Auditory system
• Auditory hypersensitivity
• Health effects of noise pollution
• Tinnitus
• Misophonia
• Otoacoustic emission
• Safe listening
• Sensory processing sensitivity
• Recruitment (medicine)
• World Hearing Day
• Hearing Health Foundation

• Hyperacusis Research, Ltd.
• Hyperacusis Central Website
• Hyperacusis Central YouTube