Category Archives: research methods

More Tidbits on Memory…and a Clip You Can Watch WITH Your Kids

2.5 - 3 years, 22-27 months, Baby Brains, Devevelopment in general, Language development, Memory, research methods, Studies

Finger w-1.string 
 So many fantastic thoughts and comments lately. What a great readership! Some really interesting questions asked/points raised about memory. They jogged my own noggin' (noticeably on the decline in recent years) of a few related studies. Here are the nutshell versions:

1. One of the ways researchers get memory in people of all ages is to compare how easy it is to learn something for the first time, compared to when we have to learn it again. For example, in lots of traditional memory studies with adults, the researchers gave their participants lists of words or word pairs (sock-orange) and looked at how long it took to learn them. Then after some substantial delay, when the participants no longer consciously remembered the list, they brought them back and looked at how long it took them to learn the same list to perfect recall again. The difference in the time it took at time 1 and time 2 is termed "savings" which basically shows that you unconsciously retained or REMEMBERED some of the list. For more on this idea and the guy behind it try here. 

Of course, we're not going to give a baby a list of words to learn, but just think of the task in terms of something that babies CAN do. For example, in one study infants of just a few months were put in a crib and their leg was connected to a string (such as by a a loop around their ankle). The point was to see how long it took the baby to figure out that if they kicked that leg vigorously, something fun would happen (e.g. a clown doll would appear, or they'd hear a funny sound, the lights would flash etc.). Then after a delay, they brought the babies back and put them in the same crib, same set-up etc. If they got the "leg kick = funny event" link more quickly, the researchers would conclude that the babies REMEMBERED what they needed to do. Oh there's always a way to get inside that amazing baby head…

2.  The stuff you have to remember to do in future – take your medicine at 2pm, TAKE A HOLIDAY GIFT IN FOR YOUR CHILD'S TEACHER BEFORE THE LAST DAY OF SCHOOL (I'm just sayin'…) – is called prospective memory (as opposed to retrospective memory, for things in the past). It's one of the first things to go when you get older. That's your head's up. 

3.  Yes, there is such a thing as photographic memory – when you can picture in your mind the actual material you want to remember, in the place where you first learned it. That's as in, you are writing an exam and you can picture in your head the page in the text book where you read it AND YOU CAN SCAN THAT PAGE TO FIND WHAT YOU ARE AFTER. It's not exactly common. Usually fades by later childhood (11 or so). Any takers?  Did any of you do this?  I definitely relied on this in school, even later on, but it got way, way harder as the years went by. I'm not sure how good a measure of photographic memory this is…but if you have a few minutes on your hands (ha ha ha…) or insomnia, Try this. 

4.  Another favourite line of research (honestly, can I really call it a fave when there are so many?) specifically targets childhood amnesia. Here's a link to the primary researcher's homepage if you want to have a browse. I cannot help but highlight one of her coolest recent findings. Ya know how excited I get about these things…

The researchers visited young children (about 2-3 years of age) in their homes and taught them a novel event. A machine would actually "shrink" a toy you put inside it. Read: Child puts a big toy in the front opening of the machine, then closes the door. Some flashing lights and machine like sounds go off, then they open door and find a miniature version of the toy inside. Yes, of course, it's been replaced with the mini one by way of the back door and another researcher or something, but boy do they go for it!  It's amazing!!!. This all happens at an age when language is fairly limited but then develops amazingly quickly. They know because they actually measure the children's language skills. 

Then after 6 months or 1 year, they go back to visit the same children and basically probe to see if they remember what happened on that first visit, now "ages" ago as far as they are concerned. The probing includes asking them to talk about it (verbal measure), asking them to pick out pictures of e.g. some of the toys they shrunk (visual recognition) and asking them if they remember how to work the machine (behavioural re-enactment). And oh yes, they measure their language skills again. Get this: Even though children remember what happened (as shown by their performance on the visual recognition and behavioural measures – both non-verbal), their memories are limited to the vocabulary they had AT THE TIME the shrinking machine thing took place. That is, even though they now had WAY better vocabularies, they described the event only in terms of the language they had AT THE TIME THEY EXPERIENCED IT!  This suggests of course that our so-called infantile amnesia is linked to our limited capacity to code or store our experiences in words when our vocabularies are so very limited. Note that as the children had good non-verbal memory of the event, they clearly registered it. It's just that they were limited in their ability to access those memories verbally. So perhaps this helps to explain why we later can no longer access those early memories and integrate them into our autobiographical memories when we are older and rely more on storing and accessing memories verbally. Hmmm…

6. Finally, to help keep your internet-using guilt at bay and to end the week on a lighter note, here's a fun clip on memory that you can actually watch WITH your kids! 

Now just remember to watch it. Good weekend.

—Tracy

When Parting May Not Be Such Sweet Sorrow

12-17 months, 18-22 months, 2.5 - 3 years, 22-27 months, 3 - 3.5 years, 3.5 - 4 years, 8-11 months, Fear and anxiety, older than 4 years, research methods, Separation anxiety

Wow! That was a lot of guilt purging last week. I hope we're all travelling a little lighter this week if only because we've been reminded that we are not alone in carrying that MOTHER LOAD of guilt. Seriously, thanks for all the sharing. Not only has it been great to hear that we are not alone, but it's been great to get to know you a bit. We aim to please…so the more you tell us, the more you can help shape this site, what gets covered etc. 

In that spirit..
Last week's group carthasis started with Bella's guilt over her departure to Europe, but someone (Paola?) mentioned that she was also interested in the garden variety of separation anxiety.  I thought I"d give a little background into the research on separation anxiety (regular kind) but then leave you with a couple of questions that, to my knowledge, are not so well covered in the research literature. The first is an issue about separation anxiety that I"ve experienced with my son (there we are in the pic in those "all important" early days). I've also heard about it from friends re: their experiences with their own children. Once again, it would be great to hear about your experience…

Here's a quick "Did you know…?" to set it all up (just some highlights mind you, the literature on attachment is MASSIVE).

Fig4 1. One of the key studies that influenced thinking on human attachment came from a study with monkeys. Infant monkeys were given a choice of a). a surrogate mom made of wire, with a plastic nipple attached that delivered food or b). a similar wire mother with no food access but who was covered in a soft terry cloth. Although they nursed from the wire mom, the monkeys preferred the cloth mum (as in, they spent 17-18 hours a day with the cloth mum versus 1 hour with the wire/nipple one), even more so when food was not at issue but the monkeys were frightened by some foreign object that entered the room. You can read more about the study here. Although this finding came from a study with monkeys and not human babies, it raised the idea that food supply may not be as central to developing an attachment to a caregiver (as previously believed) as comfort and security. 

2. Of course the MAJOR line of research on human attachment came from Mary Ainsworth's work in the lab using something called the "Strange Situation". Basically, moms and infants come to the lab and spend some time in a "waiting room" of sorts (magazines for mom, toys for baby etc.). Over the course of 15 minutes, the people in the room change. At first mom is alone with baby. Then a stranger enters. Mom leaves baby with the stranger. Mom returns, then leaves again. Then the stranger also leaves and baby is alone. Stranger returns, then mom returns. Each of these scenarios last only a very short time; less than a minute to 3 minutes max. The researchers were mostly interested in what happens when mom and baby are reunited. Based on baby's reaction to mom's return, the babies were classified as either a). securely attached, b).avoidant attached or c). anxiously attached. The secure babies (about 65% of the infants tested) got upset when mom left but were comforted and quickly re-assured by mom on her return. In contrast, the avoidant (about 23%) babies were somewhat detached, did not show much emotion, even avoided mom or acted unaffected by her departure and also her return. Interestingly, biological markers (such as heart rate and skin conductance) later showed that these babies were nonetheless in distress. And the anxious babies (about 13%), were VERY upset at mom leaving, seemed upset or even angry on her return and were not easily reassured. 

The argument goes that securely attached babies, confident in a secure base to return to, are more free to explore their environment and therefore to learn. There is evidence that they fare better than avoidant- or anxiously- attached babies on complex problem -solving tasks and that they are generally better adjusted in later childhood and beyond.

3. In case you're freaking out because you don't believe that your child would react like a securely attached baby, here's something to consider. There is evidence that the proportion of babies in the different categories varies across cultures. E.g. supposedly there is a greater proportion of "avoidant" babies in studies with German infants  (although a more recent study with a German sample showed more of a "normal" distribution of babies across the three categories)  and of "anxious" babies in studies with Japanese infants.. Makes sense if you consider that parenting practices and styles definitely differ cross-cuturally, although perhaps less so nowadays what with the whole global village, internet etc. revolution.  In that case, it would be normal, and perhaps highly adaptive, for babies' attachment behaviors to reflect the culture they are being raised to function in.

4. A student of Mary Ainsworth – Mary Main – went on to do pioneering work on adult attachment. She was interested in how your memories regarding attachment with a primary figure when you were a child compared to the type of relationships/attachments that you form as an adult (in friendships but particularly in romantic relationships). Turns out that in ~75% of cases, that early style of attachment stays with you and is similar to the types of relationships/attachments formed in later life. Although, keep in mind that it has also been suggested that certain "buffering" factors can help mediate that connection. So a rough time in childhood does NOT necessarily mean that you are doomed to repeat that pattern as an adult.  

So there you go, some points to ponder. Here's what I'm interested in hearing from you:

My son has been very attached to me, since very early on. At 18 months of age, he would get upset if I left the room to go the bathroom, even if he was in the company of his father or grandparents who he knows very well and loves dearly. A good friend of mine's child went through a phase (granted he was quite young, maybe only 6-7 months or so) where he would get upset when she bent down over the sink to brush her teeth and was momentarily out of his view. Both of these kids improved immensely, but then with no warning would show this intense reaction all over again. No precipitating event, so stressful time, no new baby, move, change of preschool or daycare, illness of loss of a family member etc. Then it would subside, only to return again. And so it went. This summer,at almost 5, my son went to a day camp for the first time (for 2 weeks). He did not know a soul, it was in a location he did not know well, first time taking his own backpack, own lunch etc. But he did not even blink. "See ya Mum". That was it. Ditto the first day of school some weeks later. So we seem to have come out the other side. It's understandable to me that there may be sensitive periods in development when kids are more likely to suddenly seem anxious about separation agai
n, but sometimes he would sail through those sensitive periods without a blip and sometimes not. 

I'm interested to hear from you about "bouts" of separation anxiety. Anyone out there have a child who would "zoom" in and out?  At what ages?  What do/did you attribute it to?

Finally, as a mum of only 1, I"m always interested to know how kids with siblings cope with things. If you have more than 1, are/were your kids similar or different when it comes to separation anxiety?  Also, do you think that how the younger one or ones handled separation from you was different to how their older sibs handled it because they had sibs – read: company – to help tide them over until you returned? 

Send me your thoughts…

–Tracy

The Cat in the Hat in the Amniotic Sac: What Can Sucking Tell Us About Hearing?

0-3 months, Baby Brains, hearing, research methods, senses

Cat in the hat What's with the feline in the millinery?  As with yesterday's post, try not to shoot the blogger if you've already heard this one. It's an old study (early 80's – never mind that I can remember the time…just barely I'll have you know), but the media has gone wild with it ever since it first came out. I just could NOT think of a week of posting on methods in infant research without mentioning it. What about that title? Gotta love it!

This study used sucking to shed light on prenatal hearing.In earlier work, the researches had determined that very young infants would adjust their sucking rate to be rewarded with hearing their mothers voice (I bet this doesn't happen in the teenage years…but I digress…). Mothers read The Cat in the Hat Story or another one of two other stories to their unborn fetuses, 2x per day for the last 6 weeks or so of pregnancy. Soon after birth, the researchers measured infant sucking when they heard the story they heard prenatally vs. one of the other stories. What happened? The newborns worked hard (sucked faster or slower) to hear the story they heard in the womb – moreso than to hear the other story. By playing with this method a bit more, later work showed that it was the rhythm of the story and not the words that the babies were responding to. BTW, the babies also worked harder to hear mom do the reading over some other female voice reading the same story. This study was a real landmark in establishing at least a couple of things: 1). the state of development of hearing in the womb and 2). how the prenatal environment helps tweek perception. 

If you're now thinking "Wow, amazing how far these researchers will go", consider this: in another (now old) study a pregnant woman was asked to swallow a tiny microphone so that researchers could gain a better sense of just exactly what the baby can hear in there. Can you imagine it? "It's in the name of science ma'am. Please just please swallow the technology." 

So I'm on a roll now. Here's another interesting way that researchers have used sucking. The main question was whether information taken in through one sense (e.g. sight) is stored in such a way that it can be accessed through other senses (e.g. touch). The technical term is cross-modal or inter-modal perception. In one study, 1-month old babies were allowed to suck on either a smooth or a bumpy pacifier – but they were NOT allowed to see it. The babies were then shown two simultaneous pics, one of the smooth pacifier and one of the bumpy one. And guess what? They looked longer at the one they had sucked on but NEVER SAW, as though they recognized it. So what they had taken in through sucking or touch was stored in a more general way, a way that was accessible through another sense, sight.  

Finally, I wanted to briefly mention the use of "geodesic nets" – think "hairnets with sensors" that provide real-time information on the patterns of brain activity as the brain processes something e.g. a picture, a sound, an event etc. The baby wears a get-up like the one shown here. Newsweek Baby brain
It's not painful at all and many babies are surprisingly co-operative about the whole experience. For more on geodesic nets and language studies, put in user friendly terms, try here.

Phew. It's been a whirlwind tour through infant research this week. Now seems like a good time to ask how this stuff is all working out for you. Too technical? Nerdy? Boring? Less on studies, more on parenting connections?  It would be great to hear some feedback. I hope that even if the details were too much or we covered too much ground that you might have gained a new respect for that bundle of sweet-smelling, soft, cuddly goodness. That's one amazing brain growing in there!

–Tracy