"... somebody or something can only be "at home" when the profession lies outside"
– Konrad Lorenz (on cats)
In the old days, people allowed their cats almost unlimited access to the great outdoors. These outdoor cats had a lot to learn and lots to keep them busy and on their toes – if they were to thrive and survive. They had to: Constantly be on the watch-out for danger
Avoid aggressive-looking dogs
Locate and investigate subjects of interest
Find friends or mates
Chase small varmints
Find safe/dry resting places
Remember routes to and from home
Decide what was fun and what was not
Stay clean so as not to advertise their presence
Know how to interact with other cats
Know when to fight and when to run away
By necessity, the daily tasks of an outdoor cat riveted his attention and exercised his mind. An indoor-outdoor cat returns from outside excursions to "crash" in front of the fire or sleep it off in the master bedroom. Then, once his batteries are recharged and he has consumed a square meal, he departs again in search of adventure.
But there are dire consequences of this way of life. Outdoor cats are constantly exposed to danger and unneutered ones contribute to the unwanted feral kitten problem. Outdoor cats also run the risk of contracting serious or fatal diseases, or they may fall victim to trauma or predators.
Fortunately, well cared for cats are usually fully vaccinated, reducing their risk of picking up infections. They are also neutered or spayed, curtailing their wanderlust and stopping them from contributing to the unwanted cat population. But trauma and predators remain as significant risks, so many cats today are simply not allowed out at all. When denied access outside, cats do not have to run the gauntlet of mortal risk each day and live longer and healthier lives.
All this is very well for the doting cat owner - but what of the cat? Don't indoor cats lose something that only an outdoor life and independence bring? Not necessarily, it turns out, depending on the owner's savvy, energy and creativity. Confinement needn't be a barely tolerable imposition, as long as owners understand the challenges of their cats' indoor existence. Regarding indoor life for cats, owners have to ask themselves one question: "What's missing from this picture?" ... and then they should set about replacing or recreating the missing elements.
The first step is to consider which aspects of an outdoor life an indoor environment fails to provide. Neutering totally eliminates reproductive urges, but there are plenty of other issues that need to be addressed if indoor cats are to find themselves suitably challenged and mentally stimulated.
Bringing the Outside Indoors
Exercise: Exercise generates the mood-stabilizing neurotransmitter, serotonin, more powerfully than drugs like Prozac®. For this reason, it is every cat owner's duty to make sure their pet gets plenty of exercise on a daily basis to keep him or her stable and happy.
Kittens exercise themselves, but cats slow down as they mature. Make sure your indoor cat engages in a level of activity similar to that of an outdoor cat. Running, jumping and climbing are all activities that outdoor cats take in their stride. Providing indoor cats with climbing frames and encouraging them to chase moving toys are excellent ways to keep them lean and limber.
Predatory concerns: In nature, cats stalk, chase, and may even kill small mammals and birds. The slaughtering aspect of this behavior is not appealing to many of us, but is nonetheless natural. Even the thrill of an unsuccessful chase is enough to exercise a cat's mind and provide him with gainful distraction. In zoos, keepers often put a live fish in a pool in big cats' enclosures so that they can occupy themselves fishing. The livebait may only be put in to the pond once a week but the promise that the pool offers keeps the big cats fishing even between times. In the home, predatory outlets include: fish tanks, pet birds in cages, window bird feeders, pet rats in a cage, pull toys, rolling toys, some food puzzles (e.g. Busta® cube, Boomer Ball®), cached food treats and "laser mice." Where fish, pet birds, and pet rats are utilized for this purpose, it is the owner's duty to make sure that they are safe from harm. A safer but perhaps more sterile method of providing predatory entertainment is the use of videos showing rodents running in wheels or birds flocking.
Drinking: Imbibing water may not appear to be the most thrilling mental exercise for a cat but it can more fun if the water is flowing or dripping. In nature, cats hone on to moving water sources because flowing water is less likely to be contaminated. For whatever reason, moving water holds intense interest for some cats. For these water-loving cats, you can arrange something as simple as a dripping faucet or as refined as a water fountain for your cat's hydrophilic pleasure.
Grooming/Scratching: Grooming your cat regularly is a great bonding exercise as well as a healthy occupation that your cat will enjoy. Strategically positioned scratching posts provide an acceptable outlet for cats to condition their claws and to mark their territory. Trying to stop cats from scratching without providing an appropriate outlet is to deprive them of an outlet for a natural behavior that they probably find stimulating and invigorating.
Novelty: Outside, things are never the same twice, but indoors, this is rarely the case. Owners should strive to provide an assortment of toys and new opportunities for their indoor cat to keep him on the ball, mentally. Hide toys around the house and rotate them periodically, so your cat appreciates the newness of the game each time.
Company: Your company will do fine, as long as there is plenty of it. However, if you have to spend long hours away, consider getting another cat for your cat (better still, get two in the first place). Remember though, not all cats get on well together. They are like people in this respect. If you are considering adding a new cat to your household, consider the likely compatibility of the cats concerned. And, as an acid test, see how they get along together before making a permanent commitment. Some cats will appreciate each other and become firm friends. Other will not. Pause to consider this matter before taking the plunge.
It is a cat owner's duty to provide mentally-stimulating environment for their pet(s). If they fail to do so, psychological problems can and do arise.