a. Uncontrollable repetition of a particular response, such as a word, phrase, or gesture, despite the absence or cessation of a stimulus, usually caused by brain injury or other organic disorder.
b. The tendency to continue or repeat an act or activity after the cessation of the original stimulus.
2. The act or an instance of persevering; perseverance.
At any given time, Sam will be "stuck" on something that occupies his mind a good bit. Sometimes those things are subtle, and may even be just in his mind, but other times, he talks about them incessantly. In the past few years, we've gone through several topics, but the ones that impacted me the most were issues with the weather and then, death. When he is obsessing about weather, he'll look outside several times a day and comment that it's cloudy...which must mean rain, which means lightning, which means the power will go out and he'll be without his computer, videos, and DVD's (Oh, my!)... and that's exactly the path his brain takes him on. It can be all consuming at times, and no matter how many times I'll tell him that weather is always moving, and the power only goes out rarely, his mind will always complete the scenario he fears the most, being without power.
The weather then took a back seat to death. He just all of a sudden started asking me about dying. I tried to explain it as well as I could, but no explaining could take the fear away of his own death, and then the death of people he loves. We'd hear him upstairs wailing into his pillow about losing everyone. I could not assure him that we won't die some day, as that would be untruthful, so what we tried to do was to make it less scary. I told him that everything he loves would be a part of his life after he's no longer here. I told him that as happy as he can imagine being on earth, he'd be doubly that happy as a free spirit. It was a long process, fraught with worry and tears often, and dyspepsia for me, but he finally let it go.
Now, our focus is something actually wonderful. He is obsessed now with being "young at heart." He knows that he's 21 and that people his age don't watch Sesame Street and other shows he adores, so he's decided that he can love them because he's decided to be "young at heart." I smile and tell him he's unique and special and that not everyone gets the joy of being able to be young at heart like him. I smile at these moments when he beams, and reminds me several times a day about how he does not have to like "grown up" things because he's "young at heart." Me? I'm praying we stay stuck on this one for a long, long time. A really, really, really long time.