Hi again, and thanks very much for your reply with so much detailed information.
I can tell you're an experienced and intuitive cat parent, from your relating of the events and feeling what is effective and what is not. : ) Also, I love their names and I'm glad you didn't change them!
I agree with you that the time outs in a space with no toys is not having an effect, and with cats, who basically have short attention spans, anything more than 5 minutes is really not effective. If they have nothing to do, they'll go to sleep. You didn't mention that they cried to get out (most cats can't stand closed doors) or made a fuss at all, so their 'punishment' didn't have any meaning for them.
You're also right about the treats. They need to relate the inappropriate behavior to an action on your part, at the time it's happening. My first suggestion would be to change the configuration of the furniture so that the swagged light wire is not accessible to them from the bookcase you mentioned. That sounds like a disaster waiting to happen.
I do believe they are doing this at night, to your nightstand lamps, because they want to play (remember cats are instinctively nocturnal) and they feel any attention, even negative attention, is attention. They got you up, you 'interact' with them, and their goal is accomplished! If there is any way to prevent access to the nightstands/lamps (have them not sleep with you or not allowed in the bedroom?), and keep the nightstands devoid of any other objects (for sure, don't keep a glass of water on there!), they'll lose interest, when it's not an 'interesting' game, anymore. You can do away with the lamps, altogether, and only have lights mounted on the wall above your bed, with a cord coming down with a 'slide switch', to turn on and off. Another idea is to find a way to weigh down the base of the lamps so they can't be knocked over, or block their access to jumping up on the nightstand by surrounding the lamps with many heavy objects so they can't jump up there, at all--there's not surface for sure footing.
I realize that so far, I'm suggesting changing the environment instead of modifying their behavior, and if you love your space and the set up of your room, I understand why you wouldn't want to change anything; however, cats, as you know, are typically difficult to get out of bad habits, so, sometimes, it's easier to take a different approach.
Nighttime not withstanding, when you are with them and see one of them knocking over a lamp or doing anything they shouldn't be doing, if you're able to stand out of sight and shake a can of coins or pebbles, this sharp, sudden noise will startle the offender, and that
is an action they can relate to the behavior, immediately. You don't want them to see the sound originating from YOU, and that's how they'll associate it with their action, more effectively.
I'm surprised that they don't keep each other occupied/busy enough and continue to exhibit this attention-seeking behavior, but it's just in the personality of the cat (your male, who is the bigger offender?).
It sounds from your description like they have many wonderful toys, but please allow me to suggest this: give them the toys in 'groups' and bring out a different group every few days. When they get a different group of toys, they'll feel like they're 'new' and exciting and before they tire of them, you'll switch out the group again. Also, make sure they have a tall scratching post (or two) and/or a kitty condo with hidey holes and 'shelves' on different levels, or a cat tree, for climbing and playing. Play with more 'interactive' toys with them, like a laser pointer and the fishing pole toy (wand) you described.
I do think your male may be attempting to be 'alpha' cat over you, but you are the human, so you are always 'alpha'. If he wants to be the dominant one over his sister, that's fine; they're both felines--but with you, you're the alpha human and that trumps alpha cat! : ) He sounds like quite the 'nut', yet affectionate and lovable, and that has been the personality of all my males, so it's not surprising.
Your kitties might benefit from a cat appeasing pheromone called Feliway/Comfort Zone for Cats, which comes in both a spray and plug-in diffuser. It's available at major pet supply stores, and also online. The diffuser resembles a plug-in air freshener, but has no scent to humans. Feliway helps to relax cats, and is useful in a multitude of situations. For more information, please see: www.catfaeries.com/feliway.html
Don't plug the diffuser into an outlet they can access.
I do think they'll 'mellow' with age, and they really are still young and therefore, very active/investigative, and getting into trouble. To save your lamps (if they're not already destroyed), remove them from the tables and nightstands and see how things go with the other suggestions I've made.
I hope things will improve, soon!
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