Introduction
Purring is one of the most endearing behaviors cats exhibit. While we usually associate purring with happiness and contentment, research has shown that cats may purr for many reasons. Some interesting facts about purring in cats:
- Kittens purr to their mother cat during nursing. The purr vibrations may help stimulate milk production.
- Injured or sick cats purr during the healing process. The vibrations may promote bone density and tissue regeneration.
- Cats purr not only when content, but also when stressed or anxious. The purr may be self-soothing.
This article explores the main reasons cats purr and the possible benefits. Purring seems to be a way cats communicate their needs and promote wellbeing.
Happiness and Contentment
Cats often purr when they are feeling happy and content. The act of petting and positive social contact with humans can trigger purring as an expression of feline happiness and satisfaction 1. A cat that purrs and rubs against you is likely showing affection and contentment with your presence and attention. Purring does not always indicate happiness though; some cats also purr when they are hungry or stressed 1.
When a cat purrs during social interactions with humans, it is generally a sign that the cat feels safe, secure, and relaxed. Petting activates nerves under a cat’s skin that lead to the release of endorphins, resulting in feelings of pleasure. The combined stimulation of being petted and of purring releases more endorphins, creating a positive cycle. Purring may start as an involuntary response but become a voluntary behavior to prolong this pleasurable bonding activity with a human companion 2.
Healing and Pain Relief
Purring may promote healing and provide pain relief in cats. The frequency of a cat’s purr falls between 25-150 Hz, with the dominant frequency being 25-50 Hz [1][2]. This range overlaps with frequencies used in therapeutic devices designed to aid bone density and tissue regeneration in humans, such as ultrasound therapy at 40-50 Hz. The vibrations from purring may have similar effects, stimulating healing and relieving pain.
Research suggests cats may purr more frequently when injured or ill. Purring is thought to release endorphins that relieve pain and has a calming effect that reduces stress. By purring when hurt, cats may be self-soothing and activating their natural healing abilities [1]. So even if in discomfort, a cat may purr to aid their own recovery.
Communication
Purring allows cats to communicate a variety of positive emotions and messages to both humans and other cats. According to The Atlantic, purring is “a signal of safety and well-being” in social situations.1 When a cat purrs, it is expressing happiness, contentment, and affection. Purrs can serve as a friendly greeting, or to let humans know the cat wants attention or care. Cats may also purr during moments of connection, like when being petted, as a way to communicate bonding and trust.
In addition, kittens purr to their mother cat soon after birth. The kitten’s purr helps the mother locate her babies when they are nursing or nesting. 2 The purring signals that the kitten is healthy and content. This mother-kitten purring lays the foundation for purring serving a social communication function throughout the cat’s life.
Nursing and Suckling
Kittens often purr while nursing from their mother. The vibrations from the purring help stimulate the mother’s milk production and letdown (1). When kittens purr against the mother cat’s body it can trigger the release of oxytocin, a hormone involved in bonding, maternal behavior, and milk ejection (2).
The vibrations from purring also help guide newborn kittens to latch onto their mother’s nipples when nursing (3). Kittens are born blind and deaf, so the purring provides a form of communication between kitten and mother during feeding time.
As kittens nurse, the sensation of suckling coupled with purring helps reinforce the bond between kitten and mother (1). This multisensory experience of hearing, feeling, and tasting forms an association between purring and comfort.
Sources:
(1) https://www.quora.com/Why-doesnt-my-kitten-purr-when-I-pet-him-but-only-does-it-when-being-nursed-by-his-mother
(2) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3183537/
(3) https://feline-nutrition.org/answers/why-do-cats-purr
Hunger
Cats often purr when they are feeling hungry. This “solicitation purring” has a distinct sound that is different from the content purr cats make when they are happy or relaxed. According to National Geographic, solicitation purring contains an element that sounds like a cry or meow, while happy purrs are lower and smoother.1
Purring while being fed or when showing interest in food helps reinforce the behavior of being fed for cats. The sound of their purr stimulates their caregiver to feed them. So purring when hungry can be a form of communication between the cat and the human.2
Stress and Anxiety Relief
A cat’s purr can serve as a self-soothing mechanism when the cat is scared, injured, or nervous. The low frequency vibrations of purring have been shown to reduce stress and lower blood pressure in both cats and humans [1]. When your cat purrs near you, it may indicate that your presence has a calming effect that helps relieve kitty’s anxiety. Cats often purr while being petted as the stimulation releases endorphins that produce feelings of pleasure and comfort. Your cat snuggling up and purring softly beside you allows kitty to reduce stress, while also possibly soothing any anxiety or worries you may have.
Bonding with Humans
Cats often purr as a way to bond with their human owners and show affection. When a cat sits in your lap or rubs against you, they are expressing their trust and contentment as well as reinforcing the positive interactions. Purring solidifies those bonds between cat and human.
According to Felisway, purring is one of the main ways cats communicate their feelings of trust and contentment to us. When we pet them and they purr in response, it reinforces those positive, affectionate interactions and strengthens our bond.
Research also shows that the unique relationship between cats and humans has been developing for thousands of years. As reported by UPI, the process of cats being domesticated and bonding with humans began over 9,500 years ago. So that special connection you have with your purring cat has been evolving between our two species for millennia.
Individual Differences
Just like human voices, each cat has a unique purr that is distinctive to them. Research shows that the fundamental frequency and harmonic patterns of purring can differ between individual cats. Some studies have even suggested the possibility of using sound analysis of purrs to help identify individual cats.
There are several factors that can cause variation in purring frequency and volume between different cats:
- Breed – Some breeds, like the Siamese, tend to purr louder than others.
- Age – Kittens often purr at a higher pitch than adult cats. Senior cats sometimes develop a coarser, lower pitched purr.
- Genetics – Subtle differences in cats’ throat anatomy can affect the resonance of their purr.
- Personality – Shy, anxious cats may purr more quietly than bold, confident cats.
While all domestic cats purr, the exact tone and volume is unique to each kitty. Paying attention to an individual cat’s purring patterns can help decipher their current emotional state.
For example, a cat purring loudly while kneading may indicate a more urgent desire for attention than a soft, intermittent purr. Understanding a cat’s distinctive purring quirks takes time but strengthens the human-feline bond.
Conclusion
In summary, cats purr for a variety of reasons related to contentment, healing, communication, hunger, stress relief, and bonding. The main reasons cats purr include feeling happy and safe, relieving pain, indicating a need, expressing distress, and strengthening social connections. While the exact mechanism is debated, we know purring utilizes intricate muscular and neural control to produce its signature vibrations and sound.
For cat owners, understanding why your cat is purring can provide insight into their health, emotions, and needs in the moment. This common feline behavior demonstrates the complex social and non-verbal communication used by cats. Responding appropriately when your cat purrs can deepen the bond you share. Overall, when a cat purrs frequently around you, it is a sign they feel comfortable, safe, and content in your presence.
