Category Archives: 4-5.5 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: Losing sleep over the 4-month transition

I'm going to address a few readers' questions that have been piling up in my inbox about sleep. But I'd like to open up the floor more in the next couple of weeks to any kind of question you might have about your child's development. Feel free to email me your non-sleep questions as well as the more sleep-specific ones and we'll try to tackle them as soon as possible.  Here's a fairly typical question from that dreaded 4-month mark:

My son is 3.5 months old; born June 12th. He was a really great sleeper
right from the get go. By 2 weeks old he was sleeping atleast a 6-7
hour stretch every night. I did very little to encourage this, he sort
of developed this pattern on his own. He kept this up until about a
month ago, when he randomly starting waking up every 2-3 hours. I am
tired! I miss my sleeping baby! Every times he wakes in the night I
nurse him. He goes right back to sleep after a feed, no problem, but I
am getting sick of the frequency of wakings now.

Some background
information for you: my son is huge! he was born weighing 9 lbs 14 oz.,
and at 3.5 months he is a little over 17 lbs. Do you think he could be
extra hungry because of his size, and he needs these extra feedings? Or
do you think he is mostly habitually waking? I am reluctant to do sleep
training because he is still so young, but I am also sleep deprived. I
have a 2.5 year old at home as well, so napping during the day rarely

my son seems to be teething, and he is also obsessed with grabbing for
toys right now. Do you think all this stuff going on is disrupting his
sleep, and he may start sleeping well again in a matter of time?

First off, congratulations for being one of the lucky ones who got more than 2-3 hours of consecutive sleep at night in the first 3 months or so. Many parents don't experience that early sleepy phase. Having said that, it seems like your baby has hit the first major sleep transition with full force. We've talked about the 4-5.5 month developmental stage at some length here  and here. Go read those posts first, so you have a sense of what's going on in your baby's head — the new and amazing ways he can see the world differently and interact with you and the world differently (yes! Reaching and grasping is a new and fabulous skill he's going to be practicing). That will give you some context for what I'm about to say next: I'm very, very sorry, but there's not a whole lot you can do about his sleep in this transition stage. At least not in terms of successfully sleep-training. That doesn't mean you can't try one of the variety of methods out there, if you're so very desperate that you just need a plan of action. But many of these methods are doomed to fail because this stage is just an inherently volatile, senstive and difficult time for sleep.

To answer your last set of questions directly: Yes, I DO think that his sleep is disrupted because of these new cognitve capacities that are coming to fruition just now. Yes, he may start sleeping well again afterwards. But my guess is that he won't go easily back to "old" patterns of sleeping because children don't "regress" to old patterns, they continue to develop new ones and continue to adapt to new contexts as they are able to understand more and more about their environments. That means he MAY turn into a good sleeper again, or he may need your help learning new sleep skills. The good news is that you have only a few weeks before things re-stabilize for a while (it will not SEEM like a few weeks, it will seem more like a few DECADES, but nevermind…). At around the age of 6 months or so, if your baby HASN'T developed his own better sleeping habits after pulling through the transition period, you can choose a sleep-training technique that best suits your family's needs and implement these strategies then. Between 5.5  – 8 months, you have a much better chance of success in whatever method you try.

If you are indeed at your wit's end and need to try some sleep-training method, first read the posts I linked to above about the milestones he's hitting. Then, armed withthe "why" of what your baby's going through, pick what you think will have the best chance of working for your child and for your sanity. Just make sure that whatever sleep-training method you pick, you stick with it consistently for 3 days. If you don't seen any noticable improvement by then, you may want to cut your losses and wait for that next window of opportunity.


4 months old Part II: The love affair takes off

I promised you more about what's going on in the 4-month old baby's emotional world. With this post, I'm going to try to give you a flavour for how big a difference one month makes at this early stage in development. Many developmentalists see the 3–4 month period as the fruition of a “love affair” between the infant and the caregiver. But it is a love affair with all the qualities of a still life. It doesn’t progress from moment to moment, and that’s because babies that age can't keep track of what to expect, what happens next. The cognitive software simply isn’t there yet—not until babies reach 4 months. That’s why, before about 4 months, regardless of how intensely your baby gazes at you, no matter how giddily she cooes and giggles at the glorious sight of your smile, there is no disappointment when the interaction ends—as long as it is followed right away by something else the baby can attend to. Even when left alone on a play mat, when you've gone off to pee, to answer the phone, to get a drink, 2 – 4-month old infants will generally not fuss if they are distracted by something interesting, at least not for a few minutes. That's why distraction is such an effective means of dealing with a 3-month old's crying. Oh no! Mama's gone! Waaaaaaaa! Hey… look at that fuzzy coloured ball… rattle, rattle, bounce, rattle… mama who?

Mom-and-baby-conversation2 It is at around 4 months that mother-infant reciprocity — that intense emotional dance of gazes and coos — peeks and it's a key transition point described by Margaret Mahler, an infant observer with a background in psychoanalysis. Mahler says that at 4 months begins a phase of “differentiation” of the infant from the mother marked by a mushrooming sense of autonomy. It may seem counter-intuitive that a period of increasing closeness should lead to a spurt in autonomy. But it's no accident. The love, excitement, and learning that flow between infant and caregiver during their face-to-face exchanges at around 3-4 months push the infant into a major developmental advance, a sort of blossoming of awareness that results in a sense of a self—an I—who can act on the world out there. Yet autonomy does not mean that the bond with the parent is over. Quite the contrary. Mahler emphasizes that the baby’s sense of a unique, separate self forms the basis of a new kind of bond with the mother—a bond between two partners, rather than a fusion in which mother and baby act as parts of a single organism. Infants now begin to interact with their caregivers in a back-and-forth fashion (as I described in detail in Part I). Also at this age, infants begin to initiate play and wait for the parent to respond to them. So the onset of differentiation at 4 months is a time of both budding autonomy and increased interpersonal engagement, leading to true play for the first time ever. The time babies spend gazing at mother’s face now begins to decline, but their attraction to game-playing skyrockets. Almost any kind of game will do, as long as it involves some repetitive, expectable activity. By 5 months, infants love the feeling of excited anticipation they get while waiting for the parent to swoop down, pat or tickle them, or throw them up in the air. When they feel lonely, or bored, or tired, they are now obsessed with their new-found power to initiate their parents' engagement and they now EXPECT parents to be on call for the next game to begin.

So the plot thickens for the 4-month old. And it's not hard to see why this developmental transition is such a difficult one for so many of us parents who are trying to take a break from the fun and games for one or two blessed hours, at least between 2 and 4 am…

4 months Part I: So hard and so normal

I'll start with a confession. When my boys were 4 months, I hit my wall. I was so sleep deprived; I often got 2-4 hours of sleep / night for weeks. On a good night when my husband took several night feedings, I would get 5 hours of sleep (I know, this seems like HEAVEN for some of you right now, but I'm a sleep wuss so I couldn't cope well even with that "much" sleep). I NEEDED my brain back. So the first time we tried sleep training, the boys were 4 months. The short story is that it was a miserable failure… I was a miserable failure. There was no pattern to how often they'd wake up and how long they'd cry.  Although we'd TRY to be consistent and implement a sleep-training plan (not CIO, but still some crying was happening all the time) there always seemed to be some major issue that one or the other of the boys was going through: one started teething as early as 4 months, one would be hungry constantly and needed to  "cluster feed," the swaddle seemed too confining, the swaddle seemed too loose, one had flipped on his stomach, the other didn't burp before being put down, and so on. In sum, it sucked. And there seemed too many variables at work, too many possible and impossible baby reasons for them to legitimately need a better, less wimpy, more kick-ass, responsive, sensitive mom. So, after about a week of banging our heads against the wall with some pretty basic sleep-training methods, I gave up. And then I proceeded to lose my mind for the next 2 months. The only thing that got me through it was knowing that it was TEMPORARY. I knew I had a plan and I would put it in place… at 6 months.

Mine is not a unique or even particularly interesting story. It is SO common. So what's the deal with this age? Four months is the beginning of a major stage transition in cognitive development. Babies at this age are now beginning to coordinate simple actions, like reaching and grasping, into routines that have a deliberate impact on the world. Now your baby can actually reach what he’s aiming for, put it in his mouth, and explore it. That means that objects are accessible, reachable, touchable, and YUM, suckable. But more than that, babies at this age are beginning to develop expectations. They start being able to PREDICT what's going to happen in the world. When they reach, they expect what they reach for to be there. Having this prediction confirmed time after time gives them a sense that their actions are causing a particular effect. Piaget termed this level of cause-effect thinking “magico-phenomenalistic causality” (ah, yes, we psychologist are so hip with our terms…), which just means that the baby has a kind of magical expectation that his actions will produce desirable effects. With respect to people, these growing expectations are the key to gratifying exchanges of smiles and gestures; it's that incredibly social "aha" time when the baby realizes when I coo to mummy, she'll laugh, when I laugh, she'll laugh back! Babies will now make a noise in order to elicit a smile from the parent. A time when attention to other people is not just a static state of awestruck delight (like at 3 months and before), but a state of turn-taking, when every noise, every gesture, is offered in order to get a response from the other person. That response means everything. And so, in the middle of the night, perhaps during dreams, certainly when babies wake up throughout the night or during the "middle" of their nap, this is what they're most concerned with: re-engaging that power to socially connect, experiment with, and play with the most important people in their worlds.

When we try to sleep train at this age, we need, at some point (like, at 4 in the morning!), to cut off this quest for a reaction. And babies are not usually happy about this. If they coo, they want you to goo-goo back. ALL. THE. TIME. If they cry, they want you to run and soothe them. EVERY. TIME. They're playing with these cause and effect relationships and they want to feel like they've mastered this little world that continues to grow for them.

In short, the four month stage transition is as magnificent as it is crazy-making. I think one of the hardest parts of this time is that most parents have reached the end of their sleep-deprivation ropes. It's around this time that many of us lose all that adrenaline we've been running on and the realization of how difficult it all is, and how long it could go on for, hits hard. Maybe for some of us, an equally bad part of this stage is that we've lost much of the social support we had when our babies were newborns and our kind mothers, friends and neighbours brought us freezable dinners and words of sympathy that made us feel a little less alone. Also, many parents have to return to work around this time in their baby's life and oftentimes this seems like an impossible transition to make.

I'll post some more details about the amazing new ways that 4-month olds start thinking and feeling about their worlds. But for now, how are you coping with the 4-month stage? What's the hardest part for your family? If you've already been through this period, what do you remember about this time in your family's life?