3 Scientific Reasons Why Babies Don't Blink

Sam Westreich, PhD

Go on, try to have a staring contest with the next baby you see

Pictured: World staring contest champion, 2022 (0–2 age group).Photo byPhoto by Kevin Gent on UnsplashonUnsplash

Table of Contents

· Theory 1: Tiny eyes need fewer tears
· Theory 2: Babies have a lot to take in
· Theory 3: Babies can’t spare the dop(amin)e
· Put it all together: physical, mental, and chemical reasons why babies win staring contests

Babies are pretty useless, but they’re also fascinating. They exhibit a whole bunch of weird behaviors. Having recently acquired one for my house, I have noticed many strange actions coming from this tiniest, lovable family member.

For the first month or so after they’re born, they literally have not learned how to smile. They are born with the ability to grasp things in their tiny little hands, but it’s a reflex; they actually forget how to do this and have to re-learn to do it consciously.

And when they’re awake, they stare — at everything. Whether it’s a parent’s face, a bright pattern on the television, or a small spot on an otherwise blank ceiling, babies lock onto it with an unblinking stare.

In fact, babies don’t blink much at all. Human babies only blink 2–4 times per minute. (In comparison, the average human adult blinks 15–30 times per minute — nearly 8x more often than a baby.)

How do they do that, and why?

Why don’t their eyes dry out, like ours do if we hold them open for too long?

Is there some advantage to staring?

We’re likely never going to be able to say for certain, but here are three proposed hypotheses for why babies keep their eyes locked on you, rarely blinking.

Theory 1: Tiny eyes need fewer tears

One of the main reasons why we blink is to keep our eyes lubricated and moist. The liquid layer deposited on the outside of our eyeballs each time we blink — called the tear film — helps to smooth the surface of the eye for better focus, and delivers antibacterial enzymes and oxygen to the surface of our eye. If we don’t blink, the cells on the outside of our eye may run low on oxygen, since they aren’t supplied directly by blood vessels.

In babies, because they have smaller eyes than adults, there’s less surface area to cover with tears, and so the tear film lasts longer. Additionally, the tear film produced by babies contains more lipids (fat molecules), which also helps prevent it from evaporating as quickly.

Another benefit of tiny eyes: a smaller chance for irritants to enter them. Have you ever had a bit of sand or dust blow into your eye? You probably felt it start to water, and instinctively blinked several times to clear it.

Babies, with their beady little eyes, are less likely to get particles into the eye, and thus don’t need to blink as often to clear them out.

Those are all physiological reasons. What about neurological?

Theory 2: Babies have a lot to take in

Another theory why babies keep their eyes open so long between blinks focuses on the neurological benefits. Basically, to a baby, everything is new and confusing and not well understood. They’re just trying to understand everything that is happening around them.

We do this as well, when we focus on something. When adults are watching something closely, we blink less. Think about watching the action at a baseball game, or watching an action movie in a theater. Our eyes stay open and we blink less, trying not to miss any of the fast-paced action.

(This can be a problem for us when it comes to looking at things like a computer screen for many hours during the day. We blink less, and our eyes get dried out, causing strain and headaches.)

For babies, everything is exciting. Whether it’s watching a parent or just looking at the crazy, giant world around them, there’s a lot for them to take in. They may blink less because they’re so focused on whatever happens to be in front of them at that time.

So perhaps the wide eyes are to try and learn as much as possible.

Or, maybe it’s just all down to chemicals…

Theory 3: Babies can’t spare the dop(amin)e

The signal that ends with you blinking starts in your brain, with a chemical used for sending signals between neurons (aka a neurotransmitter) called dopamine.

Even in adulthood, we see a link between our dopamine levels and blinking. Dopamine is used for tons of signals in the brain; you might recognize it as the “feel-good” chemical that’s released when we do pleasurable activities, like shopping, eating a delicious meal, or smelling freshly baking cookies in the oven at grandma’s house.

But we see the effect of too much, or too little, dopamine in diseases. Parkinson’s disease, for example, leads to declines in the levels of dopamine available in the brain. Schizophrenia, on the other hand, causes too-high levels of dopamine.

And guess what happens to blink rates in these patients? Individuals with Parkinson’s show lower rates of blinking, while individuals with schizophrenia will blink more often than the average person.

So how does this relate back to babies? There’s no evidence that babies, overall, have lower dopamine levels; in fact, their dopamine levels seem to vary, related to the levels of the mothers. (A depressed mother may have a more irritable and fussy infant.)

But rather, a baby’s brain is still growing and developing, and it may not be able to properly interpret dopamine signals to run regular blinks. The baby may blink more once this area of the brain has had more time to undergo growth and development.

Put it all together: physical, mental, and chemical reasons why babies win staring contests

All of these hypotheses have some evidence supporting them — and there’s no rule that says that, for one to be right, the others must be wrong. The answer is likely that all of these, combined, contribute to the ability of babies to stare, unblinking, into the souls of anyone who looks at them.

  • Their smaller eyes and more lipid-rich tear film (eye moisture) helps keep them from getting dry eyes as quickly.
  • Their brain may not be fully developed enough to stimulate regular blinks.
  • And, on top of everything else, there’s an exciting and confusing world to see!

There’s a ton of crazy things going on with babies, like how they are specifically geared to smell great to us, or how we should probably be pooping on them (perhaps as a revenge tactic for what they are likely to do to us?).

Their blink rate rises steadily as they get older; by the time they’re a teenager, they’ll be blinking normally.

Thank goodness. As if teens don’t have enough things to worry about; blink rates shouldn’t be one of them.


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A microbiome scientist working at a tech startup in Silicon Valley, Sam Westreich provides insights into science and technology, exploring the strangest areas of biology, science, and biotechnology.

Mountain View, CA

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