Understanding Your Child's Stimming: What’s Happening in Their Brain and Why It Helps

What Is Stimming and Why Do Autistic Children Do It?

As a parent of an autistic child, you've probably noticed your child doing repetitive movements like hand-flapping, rocking, spinning, or making sounds. These behaviours, called "stimming" (short for self-stimulating behaviours), might seem puzzling or concerning at first.

Imagine This: What Soothes You Also Soothes Them

But before we dive into the science, let me ask you something: How do you feel when you're sitting on a beach with a cold breeze and waves breaking in front of you? It's so soothing that you feel peaceful and forget your problems for a few moments, right? Are you someone who clicks their pen continuously while thinking, cracks their knuckles, or shakes their leg without even realising it?

Stimming is something very similar to what your autistic child does, either consciously or unconsciously. The main difference is that for autistic individuals, these behaviours serve even more crucial functions for their nervous system, and sometimes they get stuck in a loop and find it harder to stop or control when they need that regulation.

Just like how the sound of waves naturally soothes your nervous system, your child's stimming behaviours are their brain's way of creating that same kind of natural, soothing rhythm. Here's what science tells us: stimming is your child's brain doing exactly what it needs to do to feel safe, calm, and organised.

Let me take you on a journey inside your child's amazing brain to understand why stimming happens and how it helps them navigate the world.

The Brain Behind the Behaviours

What’s Different About the Autistic Brain?

Think of your child's brain like a very sensitive radio that picks up way more signals than a typical radio. While a regular radio might pick up 10 stations clearly, your child's brain might be picking up 50 stations all at once – some too loud, some too quiet, and some full of static.

Research shows that autistic brains process information differently in several key areas:

1. The Sensory Processing Centres

Scientists using brain scans have found that autistic individuals process sounds, touch, and visual information differently than neurotypical people. Imagine your child's brain has volume controls that are either stuck on "super loud" or "barely audible" for different senses. This means:

A gentle touch might feel like sandpaper
Normal classroom noise might sound like being inside a jet engine
Bright lights might feel blinding
Or the opposite – they might barely feel a hug or not notice when someone calls their name

2. The Amygdala: Your Child’s Built-In Alarm System

The amygdala is commonly described as the brain's threat detector, processing fear and other emotions, and researchers argue it plays a crucial role in autism. Think of the amygdala as your child's security guard that's always on high alert.

In autistic children, this security guard can be extra sensitive. It might sound the alarm for things that wouldn't bother other kids, like:

The texture of certain clothes
Unexpected changes in routine
Too many people talking at once
Fluorescent lights humming

When the amygdala sounds the alarm, it triggers the "fight, flight, or freeze" response. Your child's body floods with stress hormones, their heart races, and they feel like they're in danger – even if the "threat" is just a fire drill or a scratchy sweater.

How Stimming Supports the Brain

The Superpower of Stimming: What Science Tells Us

Now here's where stimming becomes your child's superhero power. When your child stims, several amazing things happen in their brain:

1. Calming the Alarm System

Stimming sends predictable, controllable signals to the brain that help calm down that overactive amygdala. It's like giving your child's internal security guard a familiar, safe signal that says, "everything is okay." The repetitive nature of stimming creates a rhythm that the brain recognises as safe and soothing.

2. Balancing Brain Chemicals

Research shows that autism involves differences in brain chemicals like dopamine and serotonin, which affect mood, attention, and sensory processing. When your child stims, their brain releases helpful chemicals that:

Reduce stress and anxiety
Improve focus and attention
Create feelings of calm and well-being
Help regulate emotions

Think of stimming as your child's natural way of taking their "brain medicine."

3. Creating Sensory Order

Remember that overwhelmed radio we talked about? Stimming helps your child's brain tune into just one clear, predictable signal while filtering out all the confusing background noise. It's like giving their brain a single, clear station to focus on instead of 50 stations playing at once.

Different Types of Stimming – What’s Happening in the Brain

Hand-Flapping and Arm Movements

What’s happening in the brain: These movements activate the brain's motion-sensing system (called the vestibular system) and send strong signals through the nervous system.
Why it helps: It's like your child is conducting their internal orchestra, helping all their senses work together in harmony. The rhythmic movement also releases feel-good brain chemicals.

Rocking Back and Forth

What’s happening in the brain: Rocking activates the brain's balance centres and creates a soothing rhythm that the brain recognises from before birth.
Why it helps: This ancient, primal movement pattern helps regulate the nervous system and can quickly shift the brain from "alarm mode" to "safe mode."

Spinning or Twirling

What’s happening in the brain: Spinning strongly activates the inner ear's balance system.
Why it helps: Some children need extra input to their balance system to feel organised and alert. Spinning can help them feel more aware of their body and more focused.

Vocal Stimming (Humming, Repeating Sounds)

What’s happening in the brain: Sound creates vibrations that travel through the body and can be very organising for the nervous system.
Why it helps: Vocal stimming can help your child focus, self-soothe, or express emotions when words aren't enough. It's also a way to create their controllable sensory input.

Visual Stimming (Staring at Lights, Moving Fingers in Front of Eyes)

What’s happening in the brain: The visual system can be easily overwhelmed in autism. Creating predictable visual input helps the brain process visual information more effectively.
Why it helps: It's like giving your child's visual system a "reset button."

Tactile Stimming (Touching Textures, Rubbing Objects)

What’s happening in the brain: Recent research shows that touch processing differs in autism.
Why it helps: By choosing their tactile input, your child can regulate how their skin and body feel, which directly affects their emotional state and ability to focus.

Whole-Body Stimming (Jumping, Running in Circles)

What’s happening in the brain: Large movements activate multiple sensory systems at once and help organise the entire nervous system.
Why it helps: Big movements can help your child feel more connected to their body, release built-up energy or tension, and shift their brain from stress mode to organised mode.

When Stimming Becomes Extra Important

During Sensory Overload

When your child's environment becomes too much (too loud, too bright, too chaotic), their brain needs stimming to create one predictable signal they can focus on while filtering out everything else.

During Emotional Overwhelm

Brain chemicals like GABA, glutamate, and serotonin may explain common autism symptoms, including the need for repetitive behaviours during emotional stress.

During Transitions or Changes

Changes activate the brain's alarm system. Stimming helps reassure the brain that, despite the change, some things (like their own predictable movements) remain safe and constant.

When Processing Complex Information

Sometimes, stimming helps your child's brain organise and process information, like having background music while doing homework.

Understanding the Fight-or-Flight Connection

What Happens When Stimming Is Suppressed?

Here's something really important to understand: when your child can't stim, their brain might stay stuck in fight-or-flight mode.

When stimming is prevented or interrupted:

Stress hormones stay high in their system
The amygdala keeps sounding false alarms
Your child might have meltdowns, shut down, or develop other ways to cope
Learning and social interaction become much harder

What This Means for You as a Parent

Stimming Is Not Something to Fix

Your child's brain is doing exactly what it needs to do.

Different Environments Require Different Amounts of Stimming

In a quiet, predictable environment, your child might stim less...

Suppressing Stimming Can Create More Problems

If your child can't stim, all that sensory and emotional overwhelm has to go somewhere.

You Can Help by Understanding Patterns

Notice when your child stims...

Creating Supportive Environments

Instead of stopping stimming, you can:

Reduce overwhelming sensory input
Provide quiet spaces
Offer fidget tools
Educate others

How to Support Your Child’s Stimming Needs

Honour Their Body’s Wisdom

Trust that your child's brain knows what it needs.

Provide Sensory Alternatives When Needed

If stimming isn't appropriate in certain situations, offer alternatives...

Educate Others

Help teachers, family members, and friends understand that stimming is your child's brain taking care of itself.

Watch for Overwhelm Signs

Learn to recognise when your child's stimming increases...

The Beautiful Truth About Your Child’s Brain

Stimming Is a Natural, Helpful, and Powerful Tool

Your child's brain is incredibly smart and adaptive. Every stim serves a purpose – calming anxiety, organising sensory information, expressing emotions, or helping them focus.

Looking Forward with Understanding

Stimming Is a Solution, Not a Problem

As research continues to reveal more about the autistic brain, one thing becomes clearer: stimming is not a problem to solve but a solution your child's brain has already found. By understanding and supporting these natural regulatory behaviours, you're helping your child build confidence, reduce stress, and develop their self-advocacy skills.

Remember, every time your child stims, their brilliant brain is working to help them feel safe, organised, and ready to engage with the world around them. That's not something to discourage – that's something to celebrate and protect.

Your child's stimming is their superpower, their self-regulation toolkit, and their way of staying connected to their own needs and feelings. By understanding the brain science behind it, you can be their strongest advocate and supporter.

References

Baum, S. H., Stevenson, R. A., & Wallace, M. T. (2015). Behavioural, perceptual, and neural alterations in sensory and multisensory function in autism spectrum disorder. Progress in Neurobiology, 134, 140-160.

Brondino, N., Fusar-Poli, L., Rocchetti, M., Provenzani, U., Barale, F., & Politi, P. (2015). Complementary and alternative therapies for autism spectrum disorder. Evidence-Based Complementary and Alternative Medicine, 2015, Article ID 258589.

Crane, L., Goddard, L., & Pring, L. (2009). Sensory processing in adults with autism spectrum disorders. Autism, 13(3), 215-228.

Kapp, S. K., Steward, R., Crane, L., Elliott, D., Elphick, C., Pellicano, E., & Russell, G. (2019). 'People should be allowed to do what they like': Autistic adults' views and experiences of stimming. Autism, 23(7), 1782-1792.

Marco, E. J., Hinkley, L. B., Hill, S. S., & Nagarajan, S. S. (2011). Sensory processing in autism: a review of neurophysiological findings. Pediatric Research, 69(5 Pt 2), 48R-54R.

Morris, I. F., Sykes, J. R., Paulus, E. R., Dameh, A., Razzaque, A., Vander Esch, L., Gruenig, J., & Zelazo, P. D. (2025). Beyond self-regulation: Autistic experiences and perceptions of stimming. Autism & Developmental Language Impairments, 10, 1-15.

Neuhaus, E., Beauchaine, T. P., & Bernier, R. (2010). Neurobiological Correlates of Social Functioning in Autism Clinical Psychology Review, 30(6), 733-748.

Note: This guide is written for parents to understand the neurobiological basis of their child's stimming behaviours, using current research translated into accessible language.