For the millions of people with hyperacusis, environmental sounds can feel like an assault on the entire body, potentially leading to ear pain lasting days, or even seizure-like episodes. Because of its crippling effects, sufferers are often forced into an isolated existence potentially leading to depression. In many cases hyperacusis is secondary to another condition, adding further restrictions to one’s life, and making it more difficult to stay positive. Hyperacusis commonly occurs in those with multifaceted health conditions, i.e. autoimmune disorders, PTSD, and Lyme. Fortunately, with the growing number of cases comes an increased awareness, encouraging much needed research and treatments. To date, findings indicate hormonal and nervous system imbalances as being key factors in this condition. Although there are currently more questions than answers, estrogen’s role is one that warrants further exploration.
What is Hyperacusis?
Hyperacusis is defined as having over-sensitivity and discomfort to normal environmental sounds that are otherwise easily tolerated. This does not mean one has better hearing, but rather that the body doesn’t process sounds normally. The result is a physiological response whose mechanics are poorly identified, which may be why it was primarily considered a psychological disorder for many years. Hyperacusis affects people of all ages and its onset can be sudden or gradual depending on the cause.
The majority of research attention is focused on the closely associated condition, tinnitus. Tinnitus sufferers hear sounds that don’t exist, such as ringing in the ears. This is not all bad for those with hyperacusis since there is a close association between the two. The military is one sector that is at high risk, as approximately 50% of combat personnel from the Gulf War developed tinnitus, likely due to the significant noise and stress they endured. Overall, it’s estimated 10-15% of the population has tinnitus and 50% of tinnitus sufferers have hyperacusis. Comparatively, hyperacusis estimates for the general population are between 9-15%, most of which are associated with another condition.
Conditions associated with Hyperacusis:
- Chronic fatigue syndrome
- Mitochondrial disease
- Lyme disease
- Autoimmune disorders
- Autism spectrum disorders
- Post traumatic stress disorder (PTSD)
- Closed head injuries
- Hearing loss
- Emotional exhaustion
Stress, Hormones and Hearing
Central to auditory functioning is a finely tuned orchestra of biochemical processes. If one section is “out of tune”, it throws off the entire system or “dysregulates” it. Studies point to the important interface of the central nervous system and hormones, known as the hypothalamus-pituitary-adrenal axis (HPA-axis). Often referred to as “adrenal fatigue” a dysregulated HPA-axis can also lead to altered estrogen (and other hormone) levels. One study tested the relationship of hearing sensitivity and stress on men and women. The findings demonstrated stress levels correlated with sound sensitivity in both sexes, with the most pronounced sensitivity in women having extreme emotional exhaustion. The details of the relationship aren’t clear, but what is clear is that a relationship exists. The significance role of stress on auditory sensitivity has prompted suggestions that stress assessments be included in diagnostic and treatment protocols.
The following have links to auditory processing and nervous system functioning:
- Hormones of the circadian cycle, i.e. cortisol, DHEA
- Reproductive hormones, i.e. estrogens and progesterone
- Stress response, i.e. HPA-axis
- Neurotransmitters, i.e. serotonin and GABA
- Electrolyte balance
Estrogen and Neurotransmitters
Keeping in mind that everything must work in sync, let’s look at the role of estrogen. The following is evidence as to its role in hyperacusis. Estrogen modulates systems of GABA, serotonin and glutamine. These neurotransmitters have roles in auditory functions as well as neurodegenerative disorders, and the conditions previously listed. Serotonin is also key in directing auditory processing and its levels are deficient in several related disorders. For this reason, SSRI anti-depressants are sometimes used for treatment.
The balance between glutamate and GABA is critical to proper neurological functioning. Whereas glutamate is highly excitatory, GABA offsets this effect. In conditions associated with hyperacusis the imbalance manifests with an overabundance of glutamate. Due to the prevalence of high glutamate in autism spectrum disorders, it has been suggested it be used as a diagnostic biomarker. So what contributes to this crucial balance? Estrogen and mitochondrial function.
Estrogen and Mitochondria
Published literature proposes estrogen as having neuroprotective effects that provide a defense against nerve degeneration induced by excess glutamate. Estrogen also preserves mitochondrial efficiency and reduces oxidative stress. Simply stated, estrogen helps the body produce energy more efficiently without creating excess free radicals that set the stage for inflammation and disease. Exposure to the hormone prior to contact with toxic chemicals has been noted as offering protection.
Mitochondrial function is also necessary for the nerve’s protective coating, called myelin. Thus, supporting mitochondria is vital in this process, since GABA and glutamate rely on them to work effectively. Just as mitochondrial function decreases with age, so does GABA production. It all comes back around because many of the conditions linked to hyperacusis also have a prevalence of impaired mitochondria. The excessive glutamate also causes increased cellular calcium, which can trigger seizures in those who are susceptible.
Evidence so far warrants further exploration of estrogen and its role in hyperacusis. Unfortunately there is a void in the research as it pertains to the topic. Furthermore, it is critical to study bioidentical estrogen so as to avoid the harmful effects of synthetic hormone replacement therapy. In the meantime, there are actions one can take to support auditory processing and lessen undesirable “sound effects”.
- MSG, and food dyes
- Loud sounds
- Environmental allergens
- Anti-inflammatory diet
- Magnesium and B vitamins
- Vitamin D
- Stress management
- Regular sleep schedule
- Sound retraining therapy
- Mitochondrial support
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