Ever made eye contact with a baby and wondered what exactly they were seeing when they looked back at you?
Turns out a few researchers were certainly curious. A team led by Svein Magnussen of the Institute of Psychology has performed a study that sheds new light on the way that newborns perceive their worlds.
The First Years of Sight
They were fortunate enough to have some previous research to build on. We’ve long known a couple of things about how vision develops in newborns.
As you might guess, we’re not born with the best eyes around. That said, we’re certainly not born with nothing at all. Visual development actually starts long before birth. The very first nods toward working eyes occur at around four weeks of pregnancy, when nerves begin to form the vital connections that make our visual system tick.
A couple of months later, by week 16, eyes have already come a long way. Babies at this stage of development are actually capable of perceiving light. They’re not quite ready to open their eyes, but they will show some movement in response to light stimuli.
By the end of the second trimester (week 26), a fetus’s eyes are in about the same state as they’ll be at birth. These babies can and will open their eyes and can even respond to fairly low-level light, such as a flashlight aimed at a mother’s belly.
That’s some pretty impressive speed of development, but newborn babies still aren’t exactly renowned for their eyesight. And rightfully so – newborn vision is, in a word, practical. Even before the most recent experiment, it was acknowledged that babies were extremely nearsighted. This isn’t exactly shocking, as a newborn’s world doesn’t consist of much more than its caregivers and whatever those caregivers decide to put in front of it.
What newborns are sensitive to is light. Well, somewhat sensitive. By our standards, they’re not particularly good at picking up on it at all, and will happily sleep in a moderately-lit nursery for the first few months of life. However, light remains the first real visual stimulus that babies will respond to. Babies are also extremely fond of faces. This is something you’ve no doubt noticed if you’ve had the occasion to hold a baby; if they’re relaxed, and not fussing or flailing, they’ll generally lie back and concentrate exclusively on your face, likely making eye contact as they do. This general preference for faces also makes sense, given that these first days are a chance for a baby to recognize and bond with its parents.
After those first few gains, vision develops very rapidly. As nearsighted as babies are at birth, by the time they reach four months of life, they’re generally able to perceive relatively distant objects and may react to a parent entering a room that they’re in. They also very rapidly get better at using their eyes to follow moving objects, something that newborns aren’t particularly good at. After a couple of months, they’ll even start to develop simple hand-eye coordination – the first steps toward some parent-trying years of grabbing everything they can possibly reach.
Other higher-order visual tasks also come along during that same time frame. Color vision is a notable example; one little known fact about newborns is that they’re born completely color blind. It takes some time for that to change, but by six months, your child will have excellent color vision, on par with your own, actually.
After that six-month threshold, babies are actually pretty visually competent. They’ve got the tools, and now they’ll begin to vigorously start testing them as they move around and interact with their environments. To the initial delight and later chagrin of many parents, this is when most infants begin to get good at picking up and even throwing toys and other, sometimes more delicate, objects.
It’s around this point that some babies will actually have changes in eye color. Most newborns have extremely dark eyes, with Caucasian children’s even appearing dark blue or gray. In many cases, initial eye colors will remain what they are for the rest of a child’s life. However, in some cases, they may change, differentiating into one of many potential colors.
Going Back to Newborns…
Now that we’ve laid out what comes after newborn vision, let’s talk a little more about what scientists have recently learned about how eyes function directly after birth.
The Swedish team responsible for the most recent survey found that after only one or two days of life, newborns were able to distinguish images up to around 30 centimeters in front of them – a length that corresponds to the rough distance between a nursing mother and her child.
While previous work has had similar results, the Swedish researchers made a key change from earlier studies: they used moving visual stimuli. An awful lot of previous work had attempted to correlate infants’ reactions to stationary pictures; however, as team leader Svein Magnussen points out, newborns are adapted to see moving objects – specifically their parents’ faces.
Besides distance, though, Magnussen’s team also gained new knowledge about how babies perceive faces. The images shown to newborns in the study were faces that conveyed a range of emotional information, some being happy, some neutral, and so on and so forth. While they’ve only just started to answer the question of how well babies can pick up on these emotional signals, there is some evidence that they can comprehend at least some number of social cues – something that has been hinted at before by babies’ reported penchant to imitate the facial expressions of people holding them.
There’s obviously much more work to be done after the most recent study, but Magnussen and his team have put us one step closer to better understanding newborn vision. As this understanding develops, it may give scientists the ability to better influence and safeguard the visual health of even the youngest of patients.