What Spanking Actually Does to a Person’s Brain

Jul 17

If you grew up in a home where spanking was normal, you've probably heard the defence: “It never did me any harm.” I get it. It was common, it was legal, suggested in parenting books, and for a lot of parents, it felt like the only tool in the toolbox when things got hard.

A 2021 study out of Harvard and the University of Washington gives us something we haven't really had before: a look inside kids' brains to see what spanking actually does.

Here's the study: Researchers scanned the brains of 147 eleven-year-olds while showing them fearful and neutral faces. Kids who'd been spanked showed heightened activity in brain regions involved in detecting threat and processing emotional significance — when they saw a fearful face, their brains reacted the way you'd expect from someone braced for danger. And the pattern looked strikingly similar to what's seen in children who experienced far more severe abuse.

To be clear, this doesn't mean spanking and abuse are the same thing, or that one spank rewires a child forever. This was one study, with real limitations the authors are upfront about — it can't prove cause and effect, it couldn't measure how often or how hard kids were hit, and group sizes were small. But it adds real weight to something developmental psychologists have argued for decades: spanking isn't a "milder, harmless" form of discipline. It may be operating on the same continuum as more serious threats to a child's safety, just to a lesser degree.

What that might mean for you now: If you were spanked growing up, this research offers one possible explanation for things you may already notice in yourself: a nervous system that's quick to read a room, quick to sense tension before anyone's said a word, or slow to feel safe. Some people notice it in how they handle conflict: freezing, over-apologizing, or feeling flooded by emotion faster than the situation seems to call for.

None of this means something is "wrong" with you. It means your brain did exactly what brains are built to do — it adapted to the environment it was living in. A nervous system that learned early on that caregivers could be a source of both comfort and threat will organize itself around staying safe. That's not a flaw. It's biology doing its job.

This isn't about assigning guilt in either direction. At the time, we did not have this information and most parents were working from the same script that was handed to them. This is about understanding your own wiring with more compassion — so that hypervigilance, that quickness to brace, that hard time trusting a calm moment, starts to make sense instead of feeling like a personal failing.

Where to go from here: Nervous systems can learn new patterns. Therapy that focuses on emotional regulation and building a felt sense of safety in the body can genuinely help recalibrate these responses over time. You're not stuck with the wiring you got at eleven.

This post is for general education and isn't a substitute for individualized clinical care. If any of this resonates and you'd like support, reaching out to a mental health professional is encouraged.

Source: Cuartas, J., Weissman, D. G., Sheridan, M. A., Lengua, L., & McLaughlin, K. A. (2021). Corporal punishment and elevated neural response to threat in children. Child Development, 92(3), 821–832. https://doi.org/10.1111/cdev.13565