Infant scientist now has to learn about a real baby

The word ‘infant’ comes from the Latin word infans, which means ‘without speech’ (‘in’ = not; ‘fans’ = speak)

I’ve been studying infant development for about 20 years, but I haven’t changed a single diaper. My wife assures me that this gap in my baby knowledge will be filled very quickly after the birth of our son (in about 2 weeks). I’ve conducted research experiments on 100s of babies, at least, trying to figure out how they go from crying, pooping, speechless little creatures to crying, pooping little creatures that who speak (and backtalk). So there are some things I know about babies, but I fear that this scientific knowledge has done nothing to prepare me for the real thing.

Well, maybe fear isn’t the right word. I’m excited. I am a little anxious. I’m also curious. What’s it going to be like to see one baby every day, developing little by little. Will he hit all of the developmental milestones on time? Will he even show all of them? I know there is a lot of individual variability across infants. I’ve seen it in the data. But what will his specific deviations from the norm be? And how will I respond to them? Will I be worried despite my knowledge that individually variability is normal? Or will I even care? This baby might seem perfect to me no matter what he does and which developmental milestones he hits. I just don’t know at this point.

What I do know is that I have a lot to learn, and I’m looking forward to learning it. I’m also looking forward to sharing the experience with my wife. Although I’ve been thinking a lot about what it’s going to be like, it’s still kind of an abstract fantasy to me. The reality hasn’t set in, even though I can feel the little guy moving around inside my wife. I’m not sure if the reality really will set in until I can actually see him and hold him.

Or maybe not until I change his diaper for the first time.

Fetal Awakenings

Here is the cochlea of a 5-month-old fetus

It is fully developed by this age.  A month later it will be fully functioning. 

Hearing develops after the chemical and tactile senses. They all develop gradually, and I wonder what that must be like. Maybe like very very slowly waking from sleep – that period when our faculties are coming online. 

Nobody knows if fetuses dream, but they do spend most of their time in REM sleep. Even if they do dream, their dreams couldn’t be much different from their “wakeful” period because their experiences are narrowly limited. 

But they can hear during the 3rd trimester. How we know is from work by scientists who monitored the heart rate of fetuses while presenting sounds and saw that the heart rates changed in response to the sounds. Cool!

This is a sheep

Scientists placed recoding devices in the uteruses of sheep to estimate what kind of sound reaches the human fetuses. Apparently certain parts of our anatomy are comparable to sheep’s. 

What they hear are sounds that are muffled kind of like the speech of the grown ups on the Charlie Brown cartoons. Not enough to hear consonants but enough to differentiate some vowels and hear the intonation and rhythm of the speech. 

So as they wake from their fetal sleep into their newborn state, infants already have some familiarity with the musical qualities of language. 

Here’s how scientists have shown that. They hook up newborns to the high-amplitude sucking procedure.

They monitored sucking rate and found that infants’ arousal (measured by sucking rate) increased in response to their mother speaking versus another woman and to their mother’s language (or a rhythmically similar one) versus another language (if it’s rhythmically dissimilar). And the preference was seen even when presenting them with a Charlie Brown-like muffled version of the speech.

Newborns even showed preferences for specific nursery rhymes they heard in utero. I don’t know if there would be any reason to teach my fetal son Goodnight Moon right now, but it’s interesting to know that I could.


References:

Birnholz, J. C., & Benacerraf, B. B. (1983). The development of human fetal hearing. Science, 222, 516–518.

DeCasper, A. J., & Fifer, W. P. (1980). Of human bonding: Newborns prefer their mothers’ voices. Science, 208, 1174–1176.

DeCasper, A. J., & Spence, M. J. (1986). Prenatal maternal speech influences newborns’ perception of speech sounds. Infant Behavior and Development, 9, 133–150.

Griffiths SK, Brown WS, Gerhardt KJ, Abrams RM, et al. The perception of speech sounds recorded within the uterus of a pregnant sheep. J Acoust Soc Am 1994; 96: 2055–63.

Lecanuet, J. P., Gautheron, B., Locatelli, A., Schaal, B.,Jacquet, A. Y., & Busnel, M. C. (1998). What sounds reach fetuses: Biological and nonbiological modeling of the transmission of pure tones. Developmental Psychobiology, 33(3), 203–219.

Mehler, J., Jusczyk, P., Lambertz, G., Halsted, N., Bertoncini, J., & Amiel-Tison, C. (1988). A precursor of language acquisition in young infants. Cognition, 29(2), 143–178.

Nazzi, T., Bertoncini, J., & Mehler, J. (1998). Language discrimination by newborns: Toward an understanding of the role of rhythm. Journal of Experimental Psychology: Human Perception and Performance, 24(3), 756–766. 

Our fetus is growing up to be a newborn

This is what our son looked like at 18 weeks. I think he has my nose. Now he’s almost 38 weeks gestational age, and I can only imagine what he looks like now.

But I can feel him.

I didn’t realize before how much fetuses move. First there were the discrete kicks that I had heard about and vaguely remembered from when my mother was pregnant with my younger siblings. But now we can feel him moving around, shifting positions, hiccupping, and responding to us feeling around for him.

The doctor says he’s made his way to the desired head-down position. That’s my boy!

I saw Michael Moore speak once and heard him declare that life begins at birth. Even though I’m pro choice, I thought then and feel more strongly now that that was just about the most ridiculous statement I’ve ever heard.

I’ve known for a long time that hearing is fully functional by the beginning of the 3rd trimester (and the cochlea is at full size by the beginning of the 2nd!). I had imagined that when the time came I’d regularly talk and sing to my fetus just in case it might help with development.

But I don’t.

He’ll learn language, and we’ll bond emotionally whether I talk to him now or not. I don’t want to get in the habit of pushing his development. It’s enough of an accomplishment that he’s gotten himself head down. I'm already proud.

Dapper Dad

My favorite page so far from the book "things to do now that you're....a dad"

Damned Chimney

Three weeks until my son's due date, and we're finishing up some last-minute home improvement projects. I'm told this is called nesting. I get it. We want the home to be a good environment for this new little life we'll be bringing home.  And I'm sure he'll appreciate the effort...

But now this damned chimney! What started out as a simple tuck point has turned into a major overhaul. To be honest, we can't really afford it. But you gotta do what you gotta do.

And the chimney won't be done by the time he's born!!!

What will my son think when he sees the chimney half on the roof and half in pieces on the ground? Maybe his 2-day-old eyes won't be developed enough to see the chimney pieces, but surely he'll notice the scaffolding around the house. "Crap, my Dad must be a slouch," he'll think.

Poor little guy. I'll try and get my act together. I promise. Until then, please try to be patient and not look at things too closely.

The chimney will be rebuilt much stronger than it was.