Introduction
A cat’s purr is one of the most distinctive and beloved sounds in the natural world. For cat owners, a purring cat is a happy cat. But why exactly do cats purr, and what does this rhythmic rumbling mean? Purring is much more complex than simply expressing contentment. Cats purr in a variety of contexts, and researchers continue uncovering intriguing new information about what purring means and its effects on cats and humans.
This article will explore the meanings behind a cat’s purr. We’ll cover the mechanics of purring, how cats use purring to communicate, the proposed health benefits of purring, and what purring may signify when a cat is injured or ill. Purring remains somewhat mysterious, but scientific studies and observations by veterinarians and cat owners provide valuable insights into this unique feline behavior.
What is Purring?
The purring sound that cats make comes from rapid vibrations of the cat’s vocal folds within the voice box or larynx. As the cat breathes in and out, the vocal folds quickly open and close, producing a rumbling vibration (Library of Congress). This vibration generates the unique purring sound.
There are several theories about the exact mechanism behind purring in cats. One theory suggests that purring is created by rhythmic signaling from the central nervous system that causes the muscles of the voice box to twitch at a rate of 25-150 vibrations per second (Earth.com). This rapid twitching produces the purr sound.
Another theory proposes that purring arises from blood flowing past the cat’s larynx and vocal folds, creating a fluttering sensation that turns into vibrations and purring. This would explain why injured or sick cats can still purr even when breathing abnormally (Library of Congress).
Overall, purring seems to be an involuntary process that originates within the central nervous system and causes contractions of the laryngeal muscles at a rapid rate, creating the distinct purring rumble.
Purring as Communication
One of the main reasons cats purr is to communicate contentment and happiness. According to Whiskas, cats often purr “when they are in a relaxed environment, sending out waves of calmness.” This purring occurs frequently when being petted or stroked by their owner, as the cat expresses its satisfaction through its unique vocalization. Purring can be a greeting as well, as cats may purr when approached by their owner or another cat they are fond of, as a way to say hello.
In addition to displaying contentment, purring can be a tool cats use when seeking food or attention. As noted by 24Petwatch, “A cat can purr in response to happiness, as a coping mechanism for stress, to solicit food or attention, and to communicate to other cats.” So purring is not exclusively an expression of happiness, but can serve multiple communication purposes for cats.
Purring and Healing
Research has shown that a cat’s purr may have therapeutic effects. Specifically, the frequencies produced during purring may promote wound healing and reduce inflammation. According to one study, the frequencies in a cat’s purr range from 20-140 Hz, which happens to overlap the frequencies commonly used in bone growth and fracture healing devices.
The vibrations of a cat’s purr have been theorized to help stimulate healing on a cellular level by promoting the regeneration of bone cells. Experts speculate this effect also promotes wound healing by reducing inflammation and swelling. Some research suggests cats may have evolved to purr as a self-soothing or self-healing mechanism. So a cat may purr when injured or ill as a way to help promote its own recovery.
While researchers are still exploring the potential therapeutic mechanisms, a cat’s tendency to purr when sick or injured indicates the behavior likely plays a role in the healing process. Pet owners often observe their cats purring when in apparent discomfort or pain, lending support to the theory of purring as a self-healing behavior.
Purring When in Pain
While purring is most often associated with contentment, some evidence suggests cats may also purr when injured or ill. Cat owners have reported hearing cats purring even when severely injured, such as after being hit by a car. Veterinarians note that purring does not always indicate a cat is happy and healthy.
One theory is that the purring is a self-soothing behavior when a cat is stressed or in pain. The act of purring releases endorphins that can help relieve pain and calm the cat. According to veterinary experts, purring may be an instinctual reaction to deal with discomfort. So even severely injured or ill cats may purr as a way to self-medicate and release tension.
While purring can signify contentment, it does not necessarily mean a cat in pain is not suffering or in need of medical attention. Cat owners should watch for other signs of distress like changes in appetite, decreased activity, crying, or aggression. But the presence of purring alone does not indicate a lack of pain.
Scientific Research
Several scientific studies have explored the potential link between a cat’s purr and pain relief or healing capabilities. One key study from the Scientific American found that the frequencies in a cat’s purr (25-150 Hz) can help stimulate bone growth and promote healing. Specifically, the vibrations and sound waves at these frequencies can improve bone density and muscle regeneration.1 This may explain why cats often purr when injured or unwell, as a potential self-soothing mechanism. However, the study had limitations in that it was conducted on bones and muscles outside of the body, so more research is needed.
While interesting, there are still many unknowns about the science behind cat purring. Some experts theorize cats may purr from pain as a signaling or self-soothing behavior, but this has not been conclusively proven. Owners report cats purring when clearly in distress or pain, suggesting purring alone cannot reliably indicate a cat’s wellbeing or internal state. More research is needed to fully understand the complex motivations and messaging behind feline vocalizations.
Overall the scientific literature is limited and inconclusive when it comes to understanding if and how a cat’s purr may provide comfort or healing when the cat is in pain. Anecdotal observations suggest purring persists even in injured or distressed cats, but the exact mechanisms and purpose behind this require further study.
Expert Opinion
Veterinarians and cat behavior experts have weighed in on whether cats purr when in pain. Dr. Gary Richter, a veterinary health expert with Rover, says “cats absolutely do purr when they’re in pain, and they purr when they’re sick.” He notes it can be confusing for owners, since we associate purring with happiness. However, Dr. Richter explains purring serves a calming, self-soothing function for cats as well. According to cat behaviorist Jackson Galaxy, purring may release endorphins that relieve pain and promote healing.
There is consensus among vets that cats can and do purr when in distress or pain. As Dr. Elizabeth Colleran, a cat veterinarian in Oregon, states: “I can confirm that I have seen cats purr when I am examining a fractured limb or during blood draws. It seems counterintuitive, but they really do.” She theorizes purring may be an instinctive way for cats to comfort themselves when hurt or sick.
Owner Observations
Many cat owners report witnessing their cats purring when in apparent distress or pain. Though anecdotal, these observations provide insight into purring behaviors.
A common pattern emerges in owner accounts. Cats often purr during visits to the veterinarian, when recovering from injuries or illness, and when being comforted by owners during stressful situations.1 For example, some owners describe their cats purring after surgeries, when receiving medication, or when having blood drawn. Others note purring behaviors when their cats appear anxious or when interacting with unfamiliar people or animals.
While cat owners cannot definitively conclude that purring indicates pain or distress, many feel strongly that their cats use purring to self-soothe during difficult experiences. The context of purring offers important clues into their motivations. Overall, observations suggest purring serves multiple purposes beyond conveying happiness.
Conclusion
Based on the scientific studies conducted on purring and healing, along with the experiences and knowledge of veterinarians, the evidence seems to suggest that cats do often purr when in pain or experiencing illness or injury. While purring may sometimes indicate contentment, it can also serve as a self-soothing mechanism and may aid healing through the vibrations. However, questions remain about the specific mechanisms and functions of purring. More research would be helpful to better understand why cats purr in different contexts and what biological purpose it may serve. While purring alone should not be taken as an indicator that a cat is not in pain or distress, a pattern of purring along with other signs like appetite and normal activity levels can give cat owners assurance that their pet is not suffering.
References
[1] The Science Behind Cat Purring. Jennifer Coates, DVM. https://www.petmd.com/cat/behavior/evr_ct_why_do_cats_purr.
[2] Why Do Cats Purr? Sarah Hartwell. https://pets.thenest.com/cats-purr-11224.html
[3] Solving the Mystery of Cat Purring. Elizabeth Von Muggenthaler. https://www.scientificamerican.com/article/why-do-cats-purr/
[4] The Healing Power of Purrs. Arden Moore. https://www.vetstreet.com/our-pet-experts/the-healing-power-of-purrs
[5] Do Cats Purr When They Are in Pain? Dr. Marty Becker. https://www.vetstreet.com/our-pet-experts/why-does-my-cat-purr-when-she-appears-to-be-in-pain