Introduction
Dog whistles are high-pitched whistles that emit sounds at frequencies higher than the range of human hearing, which generally cuts off at around 20 kHz. The extremely high frequency sounds from a dog whistle are audible to dogs and other animals, but cannot be heard by most adult humans.
As we age, our ability to hear high pitched sounds diminishes. The loss of sensitivity to high frequencies as part of the natural aging process means that most adults will not be able to hear the high frequency sounds that dog whistles produce. This high frequency hearing loss explains why the whistle becomes inaudible to many humans later in life.
How Dog Whistles Work
Dog whistles emit sounds in the ultrasonic frequency range, which means at a very high pitch not audible to the human ear. According to Wikipedia, the frequency of most dog whistles is within the range of 23 to 54 kHz [1]. This range is well above the normal hearing range for humans, which is typically 20 Hz to 20 kHz.
Dogs however have a much broader hearing range, extending up to around 65 kHz according to the Whole Dog Journal[2]. This allows dogs to hear the high frequency sounds emitted by a dog whistle, while they are inaudible to humans. Dog whistles are specifically designed to take advantage of a dog’s sensitive high frequency hearing in order to provide cues and commands.
The whistle itself emits a narrow, high amplitude tone that the dog can hear clearly. But the focused ultrasonic frequencies dissipate very quickly over distance, reducing potential disturbance to humans. This allows dogs to be selectively signaled even when in close proximity to their owners.
The Human Hearing Range
The normal human hearing range refers to the range of sound frequencies that a healthy young human ear can detect. According to research, a healthy young person typically has an audible frequency range of around 20 Hz (hertz) at the low end to 20,000 Hz at the high end [1]. This means humans can hear sounds ranging from a low rumble to a high-pitched whine.
However, the human hearing range declines with age, usually beginning around 8 years old. Specifically, it’s the upper frequency limit that gets reduced over time. By middle age, most adults have lost the ability to hear above 15,000-16,000 Hz. By age 60, the upper limit of hearing tends to be around 12,000-14,000 Hz. The reduction is more pronounced in men compared to women [2].
In summary, while young children and teenagers can hear up to around 20,000 Hz, this high frequency hearing acuity declines with age. By mid to late adulthood, the upper threshold of human hearing is typically 14,000 Hz or lower.
When Humans Stop Hearing Dog Whistles
Most humans can hear sounds in the frequency range of 20 Hz to 20 kHz, although this range decreases with age. By adulthood, most people can’t hear sounds above 16-18 kHz.1 Dog whistles emit sounds in the ultrasonic range starting at around 23 kHz and going up to over 100 kHz, which is above what most adult humans can hear.
The ability to hear high frequencies declines steadily with age due to natural hearing loss. The loss of hearing higher frequencies starts in early adulthood and progresses with age. By the 60s, most people have lost almost all hearing above 14 kHz.2 This age-related high frequency hearing loss is known as presbycusis and is caused by changes to the anatomy of the inner ear.
Therefore, most people are unable to hear dog whistles above the age of 16-18. By the 60s and 70s, almost no adults can still detect the ultrasonic frequencies of a standard dog whistle. However, the exact age this high frequency hearing disappears can vary based on the individual.
Causes of High Frequency Hearing Loss
There are two main causes of high frequency hearing loss:
Age-Related Hearing Loss
As we age, the tiny hair cells in our inner ear start to deteriorate and become less efficient at converting sound waves into electrical signals that our brain interprets as sound. This natural aging process typically causes hearing loss in the high frequency range first, making high pitched noises like birds chirping or certain consonants in speech harder to hear (Source). Age-related hearing loss, known medically as presbycusis, starts gradually and progresses slowly as a person gets older. It usually impacts both ears.
Noise-Induced Hearing Loss
Exposure to loud noises, either in a single intense burst like an explosion or over time with repeated exposure, can damage the hair cells in the cochlea that detect high frequency noises. Common causes include regular exposure to noise over 85 decibels from heavy equipment, machinery or concerts, as well as sudden extremely loud noises like gunshots (Source). The higher the decibel level and the longer the duration of exposure, the more likely noise-induced hearing loss will occur, often in the high frequency ranges first.
Other Signs of Hearing Loss
In addition to not being able to hear high-frequency sounds like dog whistles, there are other symptoms that can indicate age-related hearing loss. One common symptom is tinnitus, which is perceived ringing or buzzing in the ears. Tinnitus often occurs along with hearing loss in older adults. According to the National Institute on Deafness and Other Communication Disorders (NIDCD), over half of people aged 75 and older experience tinnitus.
Another sign of hearing loss is difficulty understanding speech, especially in noisy environments like restaurants. Background noise makes it challenging to pick out the actual conversation. Older adults may complain that others seem to mumble or that conversations are hard to follow. This difficulty understanding speech is a key indicator that hearing acuity has declined.
Hearing loss can also lead people to turn up the TV or radio volume much louder than needed. Family members may complain about the volume, but it seems normal to the person with hearing loss. This is often a gradual change as high-frequency hearing dims over time. Getting hearing tested can reveal the extent of hearing loss that may not be obvious to the individual affected.
Protecting Your Hearing
There are several steps you can take to protect your hearing and minimize damage from loud noise exposure:
- Avoid loud noises whenever possible. This includes loud music, power tools, noisy hobbies, and other sources of excessive noise. Walk away from loud sounds or turn them down when you can (CDC, 2022).
- When you can’t avoid noisy environments, wear hearing protection devices such as earmuffs or earplugs. These can lower sound levels by 15 to 30 decibels (CDC, 2022).
- Take regular breaks from loud noise exposure to give your ears a rest. Even short pauses can help prevent permanent damage (CDC, 2022).
- Keep the volume lower on headphones and earbuds. Listen at moderate volumes for limited periods of time (CDC, 2022).
- Get your hearing tested periodically to detect any early signs of hearing loss. This allows you to address problems before they worsen (CDC, 2022).
- Be attentive to muffled hearing or ringing in your ears after noise exposure. These are signs you may be damaging your hearing (CDC, 2022).
Protecting your ears from excessive noise can help preserve your hearing and allow you to continue detecting high frequency sounds as you age (CDC, 2022).
Testing Your Hearing
Audiometric testing is commonly used to map an individual’s hearing range and sensitivity. This painless, noninvasive exam measures your ability to hear different sounds, pitches, or frequencies at various volumes. An audiologist will place headphones over your ears and play a series of pure tones, each at a different frequency and loudness level. When you hear the tone, you raise your hand or press a button. The results are plotted on a graph called an audiogram, which charts the softest sounds you can hear at each frequency tested.
There are two main types of audiometric testing:
Pure tone audiometry tests your hearing threshold, or the softest sound you can hear at least 50% of the time, across pitches. It screens hearing ability at frequencies that are most important for speech comprehension.
Speech audiometry uses speech sounds and words to evaluate your hearing ability. You repeat words you hear through headphones or from a speaker at different volumes.
Together, these tests can identify hearing loss or sensitivity issues – like trouble hearing high frequencies. Testing is usually conducted in a soundproof room to increase accuracy. Regular audiometric screening can detect changes in hearing over time. It’s an important tool for monitoring age-related or noise-induced hearing loss.
Devices to Extend Hearing Range
There are certain devices that can help extend a person’s hearing range, allowing them to hear high frequency sounds again that they may have lost the ability to hear as they aged. Some options include:
Hearing aids – Many modern hearing aids are designed to specifically help with high frequency hearing loss. They can amplify and transposer high frequency sounds into a more audible range for the wearer. Styles like in-the-canal hearing aids are less visible and can improve mild to moderate high frequency hearing loss in adults (1). Features like directional microphones and noise reduction help hearing aid users pick out high frequency sounds against background noise.
Assistive listening devices – These portable systems can also help make high pitched sounds more audible by increasing volume and filtering out background noise. Devices like personal amplifiers, FM/loop systems, and infrared systems pair with headphones or neckloops to transmit sounds directly to the listener (2). This improves clarity for high frequency sounds.
Smartphone apps – Apps like Pet Sounds, Dog Whistle, and other sound generator apps can produce adjustable, high frequency tones. While they can’t replace hearing aids, these apps allow a user to test if they can detect certain high frequency sounds (3). The apps turn the smartphone into a tool to hear if any high frequency perception remains.
With some of these assistive devices, people who have lost the ability to hear high pitched noises like dog whistles and certain speech sounds can regain some degree of high frequency hearing again.
(1) https://www.mayoclinic.org/diseases-conditions/hearing-loss/in-depth/hearing-aids/art-20044116
(2) https://www.boystownhospital.org/knowledge-center/hearing-aids-high-frequency-hearing-loss
(3) https://www.newgenhearing.com/best-hearing-aid-for-high-frequency-hearing-loss/
Conclusion
In summary, the typical human hearing range spans from 20 Hz to 20,000 Hz. Most adults can hear sounds up to around 18,000 Hz in their teens and early 20s. High-frequency hearing then gradually declines with age. By the time someone reaches their late 40s or early 50s, they usually can no longer hear sounds above 16,000 Hz. This means most adults over 50 will not be able to hear a dog whistle, which produces sounds in the 23,000 to 54,000 Hz range.
The inability to hear high pitches like a dog whistle is a natural part of the aging process. But larger-than-average high frequency hearing loss can also be caused by prolonged exposure to loud noises. To help preserve your hearing, it’s important to wear hearing protection when exposed to noisy machinery, power tools, concerts, sporting events, and other loud environments. You can get your hearing tested by an audiologist if you are concerned about your high frequency hearing range or want to track it over time.
While humans lose the ability to hear high frequencies as they age, devices like hearing aids and frequency transposition technology can help extend a person’s functional hearing range. With proper prevention and management, hearing loss does not have to be an inevitable or debilitating part of aging.