Category Archives: 5.5 – 8 months

Can You Hear That? Listening Study Yields Amazing Insights About Early Human Language

In response to yesterday's blog on clever techniques researchers use to get at the goings on of the infant brain, someone asked if the "habituation technique" I described with looking is also used with listening. If you missed that post, click here for a quick primer. The answer of course is YES!

I was going to post an example of a listening habituation study but if you read yesterday's post, you can probably figure out how that would go. Here, instead, is an example of a listening study using a different listening technique called "conditioned head turning". I wanted to include it because it is one of the more famous studies with mind-blowing findings (if you didn't already hear about it in the media), that have come from infant listening work. I hope you agree that it's incredibly cool!

Check it out:

The Scoop: All babies are born with the capacity to acquire language and which one (or ones) they end up using depends on which one (or ones) they are exposed to. So it's not so surprising that young babies can hear and tell the difference between speech sounds that us old folks can no longer hear e.g. Japanese infants can hear and discriminate between the "r" and "l" sounds in the English language more easily than Japanese adults. Interestingly, the paring down of your sound repertoire to the sounds in your language (s) of exposure happens around 10 months of age, just around the onset of language production. It's as though the brain is honing in on what it will need to find our way in the social world.

In fact, the evidence suggests that this "honing in" may apply to social stimuli in general i.e. not just language. Another study showed that young infants can discriminate between different faces of the same race, a phenomenon that holds for different races; Chinese, Caucasian, African etc. But by 9 months of age, they seem to lose that fine tuned ability and are best at discriminating faces of their own race!  Read: social input goes a long way to influencing our social perception. Here's a link to one of the relevant papers in case you're really curious.

Notice that the speech and face processing narrowing is happening around the same time? Why? Probably because it's more efficient to be finely tuned to the social environment you have to deal with, the one you need to find your way in, to have your needs met in etc.

I don't know about you, but after reading this stuff I usually have two reactions: 1). Wow! Fascinating! and 2). Holy crap it's so much responsibility raising a child. What is he being exposed to?  Do we educate bilingually?  Is he getting multiracial/multicultural input?  Is that necessarily good or bad or something I should worry about at all?  Ughhh!  Then I usually realize that time is marching on and stuff is happening anyway, like it or not. There's only so much we can control…

- Tracy

What’s going on in that sweet little head of yours?

Ever look at your baby and wander what the heck is going on in that head? Ever read those articles in magazines or newspapers or hear stuff on the radio about scientific studies on human infants (non-medical) and wonder "How the heck do they know that?".  Can't exactly ask the baby. Heck, they hardly stay awake long enough to find out anything anyway, even if they could talk.

This week I thought I'd take you behind the scenes of infant research to give you a peek into how scientists get inside that head. In a nutshell? They take advantage of the things that babies already like to do such as suck, listen to and look at new things. Looking has probably been explored the most. And dude, you'd be amazed and what we've learned from theses studies.

Looking studies typically use something called "visual habituation". The set-up looks something like this:Dadandbabycb

Mum or dad wears a pair of headphones, so they can't nudge, budge or influence baby's behaviour in any way (like try to make them look especially brilliant- kidding, kidding…). Baby is given something to look at on the screen (image, video etc.). At first the baby is interested and looks intently ("Hey, what's that?!"). But eventually, baby gets bored and starts to look away – "That again, whatever…" We say that the baby has "habituated". Then the display changes and baby sees something new. If they look with renewed interest – "What the…?!" (we call this "dishabituation")- then we know that the baby detected the difference between the old and new thing. That's it.

Ho hum, you say. But get this, sometimes the change between the old and new thing can be VERY subtle (we're talking teeny-weeny). By tweaking these subtle changes – while keeping everything else in the displays the same – we've learned a whole host of things about what 's going on in that noggin'. And we're talking tiny babies (newborns, 1-month olds) right up to toddlers. 

Check out this example: In one study, 6 month olds who were habituated to displays of say 8 black dots on a white screen, looked longer when the display changed to 16 black dots. As the two displays contained the same brightness, density of dots, total area of the dots  (i.e. the amount of black), the researchers concluded that the infants must have detected the difference in number. We're talking 6 month olds here people, they're not counting (at least not the way we do)! Cool huh? 

Infant looking has been used to study everything plus the kitchen sink: we're talking awareness of spatial position, proportion, solidity of objects, understanding gravity, adults' intentions (did they mean to grab that object or just touch it by accident?), discriminating faces of the same race, sensitivity to facial expressions and even to rudimentary addition and subtraction (with some conclusions more hotly debated than others).  And get this: it takes longer for babies of depressed moms to habituate to a happy face compared to babies of non-depressed moms, presumably because it's more novel to them! 

Kinda makes you see that bundle of sweetness in a whole new light doesn't it? So what do you think? Are you surprised by some of these findings? Did you have other ideas about how researchers pried their way into the infant brain?  Wanna know about anything in particular about the baby brain? Send your q's and stay tuned to hear more about ingenious ways of getting at the inner sanctum later this week.

Reader’s question: Siblings and cribs and big boy beds, oh my!

So here's a GREAT question. Great in that, "wow, it covers so many issues" way and, also, great in that "holy crap where do we start?" way… I'm doing this in parts because, well, there's lots of parts:

I figured why not ask you a question about M''s sleep because OMG I'm dying here. She's 7 months and unlike her bro (now 2.5), she's not yet napping
on a flat surface.

OK, right off the bat, I just have to suggest that whatever you're thinking, the 2.5 year old will have some problems with whatever transition you're going to make, given he's in a MAJOR developmental transition. Doesn't mean you shouldn't make changes, only means that you should be aware of the crazies that might ensue. I realize I haven't written yet about the 2.5 stage on this blog. Bad me. VERY soon I'll get into the details. Like… tomorrow. As for the 7-month old… If you're going to do anything dramatic, DO IT NOW!  8 months is just around the corner and that's a tough age for change.

With D, he had a nice smooth transition to me
laying with him on the bed to nurse, falling asleep and me leaving him
there for naps. I could even move him to his crib/co-sleeper and he was
fine as he got older. He'd cry at first and then be fine. Same happened
when I night weaned him. Easy CIO and was done. Q was a
completely different story. Actually, she's a lot like how M is

Little Miss M naps in her car seat in the Graco Sweet Peace
(swing) and I can nurse her, put her in there awake, and she'll scream
a bit and then fall asleep. But it's playing music and swinging. If I
do the lay down/nurse thing with her, she pops right awake when I get
up and it's all over. Of course, I have not actually tried putting her
in a crib (D is still in there) and the playpen was a disaster
because she'd stay asleep and then roll over a few minutes in and wake
up screaming her fool head off. Admittedly, I've been lax on the naps
because I'm chasing after the other two. But, for the most part, those
are okay (although I want to get her on a solid flat surface and not
always in the swing…

You're in a great time of resilience for your 7-month old, so any major
change you want to make will probably go reasonably smoothly. You seem to be ok with some pretty proactive
sleep-training methods: you can put those in place for naptime anytime
(like, now) you're ready.

Needless to say, at night, she's still in with me and I'm not
getting any sleep. She does fall asleep and most often stays asleep
(except for the last week = teething/separation) in our bed. But when I
get in, she wants to nurse constantly, and I give in, mostly to keep
her quiet so I can catch some z's. I know that if she was in her own
bed in her own room, she probably wouldn't need to nurse, but since
she's with me, I hear her and then pop a boob in her mouth.
We're ready to move D [2.5 years old remember...] into a big bed with Q [his almost-5 year old sis] (same room -
God help me) and then move M into his crib. I THINK. D still
naps so well in the crib, I'm afraid to make him sleep in a big boy bed
for nap time when I fear he'll just get out and never nap. And M,
well, I realize some training will need to occur because good lord, the
night time especially is really killing me. I'm not averse to CIO; it
never worked with Q but was great with D. She does seem to scream
and then fall asleep if she's tired. So that's a good thing.
We were waiting to do this all in one big shift (which probably
isn't that smart), but it needs to happen. I need my bed and boobs
back. I'm not interested in night weaning, and I'll go in there 1 or 2x
if I have to, but I need her out of my bed.
So should I move D? Get another crib for M? Move him just
for night and leave him in the crib for naps (and put M in a
playpen?) Move them both at the same time?

OK, everyone following that? Yeah, YOU try having 3 kids under 5… Here's my distilled advice, after making far too many flow-charts to get this all straight. M is at a great age to make the transition from co-sleeping to her own crib. Wait another month and it will be SO MUCH HARDER. And you're really fed up, which means a lot in my book. You can't be the flexible, connected mother you want to be when you're sleep-deprived and starting to feel fed up. So, I'd say: Go for it! Move M to a crib or crib-like thingy.

But here's the problem, D is 2.5 and that means real upheaval, developmentally. The short story is that he's going through a major cognitive-emotional transition period. I'll write more about it in a post unto itself tomorrow, but one of the main components of this stage is the onset of JEALOUSY. So, before this, he didn't have the capacity to feel the real force of jealousy (yeah, he might have been whiny when he wanted you and you had his baby sister in your arms or at your breast, but NOTHING like what he's feeling now or will be feeing very soon). Because of this sudden developmental onset of jealousy, moving him OUT of his bed/crib and substituting his sister in his place will be, in short, a MAJOR diss from his perspective. Now, you could just decide that it's worth the upheaval. You wouldn't be evil deciding that, given the various constraints of available beds, cribs, boobs, and sleep deprivation. But if it was me, here's what I'd do:

I'd move M to a crib or some sort of pack and play or something, out of your bed (too bad you don't live close to me… I have two cribs I need to get rid of soon). It's  a great age for this shift for her. I'd leave D in his crib for another 4 months or so. He's sleeping in there great, he's napping wonderfully, and everything is how you'd like it to be, except that he's got the crib you'd like to give to M. MANY kids drop their naps if they're shifted to a big boy bed during this 2.5 year old stage. First off, this stage often involves sleep setbacks to begin with. If you compound these developmentally-charged sleep setbacks with a change in sleep setting all together, you may be in for some real sleep upheavals from him. The rest you thought you'd get from M being out of your bed may end up being compensated for by the crazies that might come from D. Also, switching him back and forth from his new "big boy bed" to his old crib (just for naps but not for night), where his baby sister will be sleeping at night, will be very confusing for him and might make him less likely to sleep in both settings. Many kids really get comfort from the feeling of their own space, their own bed, their little den. To try to get him to switch back and forth, in a time of transition (nap and night), will probably be very difficult.

This is really, really hard because you're balancing the developmental needs of two children, one of whom is in a great resilient stage and the other who is in a vulnerable, sensitive stage. The oldest will probably do just fine with having her brother start sleeping in her room (5 is a nice stable age). Add to the mix that your own needs have to be met and you have space constraints and it seems silly to purchase an extra crib… well, it is really tough and very typical for many families dealing with siblings and their conflicting sleep needs.

But, of course, you guys should know me well enough by now to know that
I never think things are so absolute. So… if you're desperate, and
you really don't want to buy a second crib or move M to his brother's
room for a few months, you COULD try to play the "big boy" card big
time. If you go the route of change everything all at once (OY!), here's how I'd do it: You could keep in mind D's probable issues with jealousy and let
him know how SPECIAL and BIG and GREAT he's been, so much so that
you're going to move him to his very own SPECIAL, BIG BOY bed, in his
BIG SISTER'S SPECIAL room. Really make a HUGE deal of how much you love, care, respect, need him. In other words, make this transition the foundation for addressing his probable jealousy. Take some extra time to be sensitive to what this move means to him and make it clear to him how special his role in the family is. Also, pay extra attention to his emotions and perhaps connect with him on how hard it might be for him. I don't mean to sound extra hokey, but it really is a sensitive stage in his little world.

Any other moms with more than one child who are dealing with a similar situation? How do you decide whose needs to prioritize? What would you do in this situation?