On one of my first trips to the Pacific Northwest I noticed a highway marker on I-5 just north of Salem, Oregon, that reads: “45th Parallel Halfway Between the Equator and North Pole.”
Hailing from the sunny climes of the Southwest, I pondered what that meant. On average, the 45th parallel north gets just over eight hours of daylight in winter. Add in that during the winter months of November, December, January, and February, the Pacific Northwest is sunny only a small percentage of the time (Seattle 28 percent and Portland 29 percent). After living in the beautiful PNW for 18 years I learned it means very little sunlight creates dark, depressing winters: the perfect set up for what I call the “deep blue funk,” also known as “winter blues.”
“Winter blues” is the common name for the medical condition Seasonal Affective Disorder (SAD). SAD affects certain people who live far north, or south, of the equator in the winter months due to lack of sunlight. Do cats, luxuriators of sun puddles, experience the same condition?
The National Institute of Mental Health classifies SAD as a type of depression that changes with the seasons. Common recurring symptoms start in late autumn, continue through winter, and dissipate in sunnier spring and summer seasons. They include lethargy, difficulty staying awake, increased appetite, feeling hopeless or worthless, and social withdrawal. Suicidal thoughts and behaviors may present in the most severe cases.
It’s thought that the lower sunlight of winter not only causes a decrease of serotonin, a brain chemical that regulates mood and feelings of wellbeing, but also causes an increase in melatonin, a hormone that helps regulate sleep patterns and mood.
There isn’t much science-based data to support SAD in cats, but there is the oft-cited owner survey by People’s Dispensary of Sick Animals (PDSA), a veterinary charity in the United Kingdom. It reports that one-third of cat owners said in winter their cat’s mood appeared gloomy or depressed and their appetite increased while energy levels decreased.
Changes in sunlight signal cat brains to grow a denser coat in darker months when there’s less sunlight–could there be other chemical signals?
“Cats are seasonal breeders and I would suspect that hormones, even in spayed or neutered cats, contribute to changes in their behavior, too,” says Lynn Bahr, DVM, CEO of Dezi & Roo, Just for Cats. “Housecats live in artificial environments. Their homes are cooled in the summer and heated in the winter. So I am not sure that their bodies are responding naturally to any of the seasons. Many housecats don’t have enough access to sunlight year-round. I believe this is a real problem and suspect many suffer from depression, increased appetite, and lethargy throughout their lives. It is possible they suffer from SAD all year long and not just in the winter months.”
Emotional Contagion or Real?
Emotions, such as happiness, joy, fear, anger, and sadness, are contagious. Emotional contagion means that we subconsciously read facial cues and copy each other’s emotions. Research shows that cats, too, respond to human facial expressions such as smiling or frowning.
Are cats experiencing SAD, picking up on human emotions, or just bored out of their gourd because they don’t have enough mental and physical stimulation?
“I believe it has more to do with the type of owner cats have than the premise that they are picking up on emotions,” Dr. Bahr says. “Cats who live with happy, playful, active owners are more likely to be kept stimulated and entertained than those that live with owners that sleep a lot, are depressed, and keep the house darkened.” She gives an example of moving clocks forward and backward. Cats don’t know the time changed but they do recognize a change in their owner’s habits of coming home later or getting up earlier, which is a change in the normal routine. That change may confuse some cats and cause stress.
Light therapy. This is the gold standard that fills the void of diminished sunlight during winter months. A special full-spectrum light box simulates natural sunlight, which may ease some SAD symptoms.
Lighten up. Open blinds or curtains to bring in available natural sunlight. Move your cat’s bed into the sunlight, add window perches, or read a book in a sunny corner and invite your cat to soak up the rays with you. Move playtime to well-lit areas–whether natural sunlight or under a light box, it will be good for both of you.
Increase indoor activities. Exercise does a body good. It releases feel-good endorphins that lift our mood. Increase your cat’s playtime by leaving puzzle feeders out for exploratory scavenger hunts, or surprising her with a new toy.
Take it outside. Fresh air and sunshine are two of the best cures for things that ail us. For adventuresome cats, consider a leashed walk (after you’ve practiced indoors so she is accustomed to harness and leash), an outing in a stroller, or other supervised outdoor access. Catios, window units, and fancy chicken coops revamped for cats are all wonderful outdoor options.
Dr. Bahr says, “There are many ways in which owners can give their cats the sunshine they need. It is important to provide indoor cats with this natural basic need all year long but especially during the winter months when the days are shorter.”
This article was reviewed/edited by board-certified veterinary behaviorist Dr. Kenneth Martin and/or veterinary technician specialist in behavior Debbie Martin, LVT.