Let me address in particular the case of tantrums. Children are not born to throw tantrums. Every single time a child throws a tantrum, there is always a reason. The challenging part is to find out the reason. When they are not verbal, yet, sometime it's just impossible to find out the reason. So that's a major problem for parents with children on the spectrum.
There are two routes to dealing with tantrum issues.
(1) If you know the exact cause of their tantrum, then it's easy. You draw pictures for them, explain to them what happened. Use magnetic drawing board, and perhaps index cards with mini-photo-album. Do the picture-aided talking also around bedtime. These actions can remove their resentment right away. I would say that whenever I know the cause of my son's tantrum, I have always been successful at removing his resentment.
Very often the cause of resentment is simply because of rush. Parents have other responsibilities. Parents have deadlines. In those cases, adults need to do whatever needs to be done, there is no time for arguing, even if the kids don't like it. For those cases, you simply need to explain to them afterwards, and make them understand the reason behind the rush.
(2) If you don't know the cause of their tantrum, then it's much more difficult. Bad situations may happen outside of your home. The bad feeling may be coming from school, or from some past events that nobody remembers anymore. That's a very challenging part for parents, because you are working in the dark, and your children cannot tell you the exact source of their discontent.
Inside the minds of these children, once they get into the tantrum mode, there is an auto-feedback loop in their thought process. Almost nothing you can do can make them change their opinion. The more you talk about it, the more you try, the worse it gets. So, that's not the right moment to solve the problem.
If you just need to distract the attention of your children, you can always give your tablet PC or smartphone for they to play. But that is only a temporary band-aid.
It takes time and effort to remove their resentment. What you want to do is to connect their bad memories to their good memories. And here is how you can do it.
Step number one: when they are mad, draw a picture of the moment, with an index card is possible. (Magnetic drawing board is OK, too, if they already have longer-term memory.) That will "record" the moment of bad memory. Keep the card, or if you used magnetic drawing board, draw the picture of your children being mad, again, at bedtime. That's step number one.
Step number two is to connect a good memory to the bad memory. Take your children out for fun events. Whatever you do would be fine. In my case I take my son out for elevator rides. Or sometimes I talk him after I go pick up some of his favorite food items for dinner (fish taco, rice, pizza, whatever.) Or sometimes I play with him when he is building elevators/houses/car washes with building block toys. When your children are at their happiest moment, that's when you want to make connection to their bad memory. At the moment of their highest happiness, you show them the index card where they were mad, and ask them: "are you still mad, or are you better?" Things like that, use some very gentle questions to remind them about their bad moments. Then, again, at bedtime, you remind them about the good/fun moments they had today, and remind them that you have shown them about their bad moments (with card), today, too. (With my son, I usually don't need to use cards any more, he is fairly verbal. But at bedtime I do still draw pictures on magnetic drawing board.)
Step number three: connect the bad memory to good memory. Next time when tantrum happens, now you have one more tool. You can can remind your children that you have been nice to them, that you have had fun with them. At bedtime, again, draw pictures and explain to them the whole story, from the first incident, to how you took them out for fun, to how you gave them some of their favorite food or toys, to the most recent time that they threw a tantrum. Ask them whether Daddy/Mommy (you) is their friend, ask them whether Daddy/Mommy is nice to them. Ask them whether Daddy/Mommy loves them. Ask them whether they love Daddy/Mommy.
So the three steps are:
(a) save the memory of bad moments, drawing on index card helps. DON'T try to solve the problem when it is already happening
(b) connect a good memory to their bad memory. You remind them of their bad experience only when your children are at their happiest moment
(c) connect their bad memory to their good memory. Next time when tantrum happens, remind them what nice things you have done for them
Repeat these three steps, again and again.
For "repulsive" loops, such as sensory problems or tantrums, the modulation process is "inward": you CANNOT start at the moment of their sensory problem or tantrum. You must wait until their moment of maximum fun/happiness, and then modulate the bad experience into the good experience. It's a very simple principle: no matter whether it's outward or inward modulation, you always want to start with fun/happiness, so that you can channel that positive energy into their negative moments, and break the undesirable auto-feedback loop by establishing more connections inside their brains.
To solve sensory and tantrum issues, I always tell parents that the children need to be happy first. That's the key. You need to saturate your children's brains with happy experiences. Those happy experiences are you anchor points. Without those anchor points, it'll be virtually impossible for you address their sensory or tantrum issues.
The inward modulation is less efficient than the outward modulation, so you will need to be patient and repeat the whole process several times.
There is no mystery about autism. It's all about making more and more connections inside your children's brains. You re-wire their brains and make happy energy flow to the negative areas inside their brains. That's all.
