What Autistic Pruning Teaches Us About Sensitivity, Overload, and the Beauty of Holding On

By Tim Aiello, MA, LPC, NCC, ADHD-CCSP, ASDCS

There was a time when I thought I was just “too sensitive”—to sounds, to emotions, to life. I was constantly told to toughen up, let things go, or stop overthinking. But the truth is, I wasn't holding on because I lacked resilience. I was holding on because my brain was.

This brings us to something called synaptic pruning, and why it matters so much for autistic adults.

What Is Synaptic Pruning?

Synaptic pruning is a natural neurological process where the brain eliminates unused or unnecessary synaptic connections between neurons. It happens primarily during childhood and adolescence, acting like a "spring cleaning" for the brain. The goal? To streamline neural pathways so that the brain can function more efficiently.

Think of it like tidying up a cluttered desk: removing old papers and broken pens so you can find what you need more easily. For most people, this process happens automatically and aggressively in early development, especially in the prefrontal cortex—the part of the brain responsible for executive function, emotional regulation, and decision-making.

How Synaptic Pruning Works Differently in Autism

In autistic individuals, research shows that synaptic pruning is significantly reduced. Instead of clearing out excess neural connections, the autistic brain retains more of them.

A groundbreaking study by Tang et al. (2014) found that children and adolescents with autism had more synapses in their cortical tissue than neurotypical peers. Their brains weren’t overgrown—they just hadn't eliminated as many connections. The result?

A more densely connected brain, with increased activity in regions related to sensory processing, attention, and memory.

In other words, we hold on to more.

The Impact of “Too Many” Connections

Now, holding on isn’t necessarily a bad thing. There’s evidence that reduced pruning is associated with enhanced perceptual skills, pattern recognition, and memory. That intense focus we can have? That deep recall of seemingly minor details? That’s not a coincidence. It’s structure.

But it also comes at a cost. When our brains are wired to take in more—more sights, more sounds, more emotions—overload becomes a daily risk. We're not just distracted by background noise; we're processing it all. We're not ignoring the emotion in someone’s voice; we’re absorbing it, maybe even carrying it.

This is why sensory sensitivity, emotional overwhelm, and rigidity in routines are often misunderstood. They’re not behavioral quirks or preference issues. They’re the product of a brain that doesn’t filter or let go the same way. The autistic brain doesn't prune input—it archives it.

Pruning, the Polyvagal Lens, and Safety

From a Polyvagal Theory perspective, this retention of neural data can keep the nervous system in a heightened state of alert. When you're constantly registering cues of threat—bright lights, subtle changes in tone, crowded spaces—it becomes harder to feel safe enough to drop into regulation.

And without that sense of safety, the social engagement system (ventral vagal pathway) struggles to activate. Instead, many autistic adults stay in a chronic state of sympathetic arousal (fight/flight) or dorsal shutdown (freeze/fawn), often without knowing why.

Understanding how the autistic brain is wired—how it physically holds on to more connections—helps validate this experience. It’s not anxiety without cause. It’s not emotional dysregulation out of nowhere. It’s a brain and body doing their best to process everything, often all at once.

Why This Matters for Adults

We often talk about autism through a childhood lens—meltdowns, stimming, early intervention. But adults still carry these neurological traits. The pruning process didn’t “catch up.” If anything, it laid the groundwork for:

• Hyper-awareness of surroundings

• Difficulty transitioning between tasks or topics

• Intense emotional memory

• Deep empathy that can look like social withdrawal (because it’s exhausting)

• The need for quiet, order, and space—not because we’re antisocial, but because our systems are trying to survive

  
  

For many of us, understanding pruning is a relief. It explains why we can’t just “tune things out” like others do. It’s not about being fragile. It’s about having a brain that remembers, notices, and feels more.

Reframing the Narrative

Reduced pruning doesn't mean we're developmentally stuck. It means we're differently tuned. Yes, it may make sensory processing harder. But it also grants us a richness of perception that many neurotypical people miss.

We see the small things. We hear the tone beneath the words. We remember what mattered to someone three years ago.

That’s not brokenness. That’s depth.

And maybe the world doesn’t always understand that. Maybe even we struggle to understand it at times. But this kind of brain—this kind of processing—is profoundly human. It just doesn’t fit neatly into systems built for speed and efficiency.

What Helps?

If you're an autistic adult navigating life with a brain that doesn't prune the way others do, here are a few supportive ideas:

1. Sensory Hygiene

Create rituals that soothe the senses: weighted blankets, noise-canceling headphones, dim lighting. These tools aren’t luxuries—they’re necessities.

2. Mental Offloading

Your brain is holding a lot. Use visual systems, mind maps, or even voice notes to externalize what’s swirling inside.

3. Structured Downtime

Rest isn’t just about sleep. It’s about creating low-input space where your brain doesn’t have to process so much—walks, baths, music with no lyrics.

4. Validation

Surround yourself with people who get it. Whether that’s therapy, community, or online spaces, validation is a form of nervous system regulation.

Final Thoughts

Autistic pruning—or the lack of it—doesn’t make you defective. It makes you different. It means your brain is less interested in tidying up and more focused on holding on.

And yes, that can be overwhelming. But it’s also incredibly powerful.

We don’t need to be less sensitive. We need a world that’s more sensitive to us.

References

• Tang, G., Gudsnuk, K., Kuo, S. H., Cotrina, M. L., Rosoklija, G., Sosunov, A., ... & Sulzer, D. (2014). Loss of mTOR-dependent macroautophagy causes autistic-like synaptic pruning deficits. Neuron, 83(5), 1131–1143. https://doi.org/10.1016/j.neuron.2014.07.040

• Courchesne, E., Campbell, K., & Solso, S. (2011). Brain growth across the life span in autism: age-specific changes in anatomical pathology. Brain Research, 1380, 138–145. https://doi.org/10.1016/j.brainres.2010.09.101

• Porges, S. W. (2011). The polyvagal theory: Neurophysiological foundations of emotions, attachment, communication, self-regulation. W. W. Norton & Company.