There appears to be a serpent in the paradise of stimming. The activity can be so delightful that it becomes addictive—distracting autistic people not only from what other people want done (schoolwork, hygiene, ABA therapy), but even from they themselves want and need (food, sleep, communication, a meaningful life). Many autism “experts” and parents worry about the potentially addictive nature of stimming, but most autistic people who write for an online audience unabashedly celebrate their stims, viewing them as wholly positive. Many of them believe stimming actually helps them function better in the world, by allowing them to concentrate on what they need to do. For these people, the stim is an effective tool, as well as a source of joy.
There are, however, a few autistics who do view stimming as potentially problematic. Ido Kedar, for example, writes:
It may start small but it can take over your life- not so much life, but all you do is less important than the stim itself if it is compelling. So, it is an escapist drug and it is addictive. I used to stim a lot as a young boy, especially before I could communicate. Now I stim less because I am engaged in life at a normal level, so I stay in the world as much as I can. I am thrilled about that because I don’t want to live in Autismland flapping, tensing, and twirling my life away.
But to describe stimming as “addictive” certainly does not justify attempts to separate autistic individuals from their stims–especially if the goal is simply to make them “look normal.” If the stim is a source of pleasure, it should obviously be tolerated at least some of the time. Why should autistic people not be allowed to experience their own pleasures? And if a stim actually helps the stimmer achieve his or her goals (in other words, if it helps them focus better)–as many autistics claim–it should obviously be tolerated all of the time.
Intervention may be warranted if stimming seriously detracts from quality of life, or if it is self-injurious. However, even here, great caution is warranted. Stimming often serves as an essential coping mechanism (a response to physical or mental distress). Determining whether this is the case is no simple task, not only because the source of distress may not be obvious to neurotypicals, but also because autistic people (especially children) often have trouble identifying the source of their troubles, let alone communicating them to others. An autistic child may not realize that the unending buzz of the fluorescent lights in her classroom is setting her nerves on edge, and so she cannot ask her teacher to turn them off. She may not be aware that she dreads the bullying coming up during recess time, and is stimming to relieve anxiety. But if it can be determined that physical or mental distress is the cause of the stim, then the next step should be to see whether that distress can be alleviated in some way. ONLY if the cause of distress can be eliminated or greatly reduced should other activities such as schoolwork, hygiene or therapy be gently promoted. And it may well be the case even then, that stimming will help the autistic individual focus better on what needs to be done.
But what if the stim is self-injurious—that is, what if the autistic person is desperately trying to smother pain they cannot control with a different kind of pain (head-banging, arm-biting, etc.) that they can control? Extreme stims often (perhaps always) are a response to extreme distress that cannot be expressed in other ways. A non-verbal teenager may not be able to tell his doctor that impacted wisdom teeth are causing him constant suffering, and that he is banging his head against the wall in an attempt to distract himself. In that case, the only humane solution is to try gently to replace the harmful stim with a less destructive one—for example, head-banging and biting can often be replaced by deep pressure. Under no circumstances, however, should aversives—bitter tastes, sudden loud noises, disgusting smells, or the application of new pain, such as electric shocks (and yes, these aversives are all still in use today, even though there is no scientific justification for them)—be used to eliminate self-injury. There are few things crueler than punishing a child (or adult, for that matter) for stimming, if the stim is all that stands between them and despair.
 Cynthia Kim, “A Cognitive Defense of Stimming,” from her Musings of an Apsie blog: https://musingsofanaspie.com/2013/06/18/a-cognitive-defense-of-stimming-or-why-quiet-hands-makes-math-harder/
 Some useful tips may be found on http://fuckyeahstimming.tumblr.com/tagged/Replacement-Stim-Requests-and-Suggestions