Posted on: March 22nd, 2016 by Dr. Dale Rubenstein

Cats’ five senses are the same as humans: sight, hearing, smell, touch and taste, but there are obvious differences both in anatomy (we can’t swivel our ears to locate the direction of sound) and function (we can’t see a mouse scurrying across the floor in the dark–thankfully!). The sensory organs of cats allow them to hunt, jump and climb, enabling cats to survive. Knowing how to protect your cat’s sensory organs will help keep your cat healthy and happy.

Cats have excellent night vision, which enables them to hunt at night. While cats can’t see in total darkness, they can see much better in dim light than we can.

Eye problems you would notice include changes in coloration (redness, cloudiness), discharge, changes in pupil size (one side larger than the other) or blinking/holding one eye closed. Also, cats have a “third eyelid” that acts as a protective screen. If the third eyelid is visible, this may mean that your cat is sick. Eye problems are painful and can worsen quickly, so scheduling an exam is in order; this is not something that should wait over a weekend.

A cat’s ears are very sensitive, and cats can hear a wide range of sounds including high frequency (ultrasonic) that humans are unable to hear. A cat will usually turn its head to the direction of the sound, which helps both visually and with hearing. As with people, the inner ear is involved in maintaining balance.

Signs of ear problems in cats include scratching or shaking their head, holding one ear down, swelling, odor or discharge, or sudden loss of balance. You may also see wounds or scabs on or near the ear. You may see multiple purple bumps (adenomas) on the inside surface of the ear canal; these may result from chronic inflammation. Non-healing wounds may indicate tumors.

Some ear problems can be diagnosed during an office visit, by examining the ear and performing microscopic exam if there is a discharge. Because cats have a deep S-shaped ear canal, anesthesia may be needed to fully examine, diagnose and treat deeper ear problems.

Cats have a very acute sense of smell, that helps locate prey or danger (for our indoor cats: unfamiliar animals, people or changes in their environment). The most common nasal problem in cats you would observe at home is sneezing, most often due to upper respiratory virus. While vaccination helps prevent more serious disease, many cats are infected with respiratory viruses as kittens and remain life-long carriers; the virus can shed with stress (anesthesia, travel) or steroids (used to treat inflammation and allergies).

Other causes of sneezing in cats include dental infection, which can extend into a sinus. Also, cats can get nasal polyps which are inflammatory/benign, often causing “noisy” breathing, possibly with mouth odor. Polyps are usually seen in younger cats; surgery is usually needed to treat polyps. Older cats can get nasal tumors/ cancer, so if sneezing starts in an older cat, testing (imaging, biopsy) may be needed to determine the cause. Anytime sneezing persists, or if your cat is “acting sick”, has trouble breathing or is not eating well, an exam is in order.

Cats do live up to their reputation as “finicky” eaters, which in the wild, prevents them from eating something that might be toxic. Unfortunately, pet food manufacturers do their best to figure out what flavorings cats like best, which frequently leads to excess weight gain. Their appetite is often perked up by a new food, but this is usually short-lived (just after you bought a case or a large bag, they will decide they don’ t really like that food).

The rough surface of the tongue contains taste buds and also helps remove dirt from the fur. When you have two companion cats, you will often notice one grooming the other on the hard-to-reach spots.

Dental pain can be a cause for a cat to change its eating habits. Cats may chew on one side of the mouth, may let food fall or may avoid certain foods; you may also notice an odor from your cat’s mouth. Ulcers, wounds, foreign bodies (sticks) or tumors are other causes for mouth odor and sometimes cause a change in shape of the face or jaw.

Because the first and most common sign of many illnesses in cats is a drop in appetite, any time your cat “becomes extra finicky”, take this as a warning that your cat should be seen promptly by your veterinarian.


A cat’s whiskers are very sensitive to the slightest touch. Whiskers are used for monitoring the environment and are used in a friendly greeting with another cat. The cat has four rows of whiskers on the upper lip on each side; smaller groups of whiskers can be found on other body parts including above each eye, on the cheeks and on the backs of front paws. You will note that a cat sheds whiskers as it does other fur, but whiskers should never be cut, as this alters the cat’s ability to orient itself.

Know what is normal for your cat; if you notice a change, please contact your veterinarian. It is always best to treat a minor problem before it becomes more serious and more chronic.

Thanks to Dr. Nicholas Dodman and Catnip News, Tufts Univ. 2010, for background information for this post!