Category Archives: Memory

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 I was younger I could remember anything, whether it happened or not” — M.Twain

Memory

After the last post and your comments, I'm completely into thinking about memory processes and talking more with you about them. Have you guys seen this? I saw this video a while back but it came back to me as I was thinking more about memory and how odd and awesome it is. If you haven't seen it, prepare to be blown away.

And here's an episode of Radiolab on Memory and Forgetting. It is so, so good. You guys know how much I love Radiolab. This episode does such a nice job of explaining how memory in the brain works — they have a knack for providing just the right metaphors. They also elaborate on LeDoux's work that I referenced in the last post on emotional memories. Many of the comments on the last post made some allusion to how amazing it was that we (or our children) DON'T remember things that seem so… memorable. In this Radiolab episode, you'll here more about how common it is to "lose" memories, how biased the memories we DO retain really are, and how easily we can create "false" memories. Fascinating stuff…

– Isabela

More on autobiographical memory: What do we remember from our childhood and why?

2.5 - 3 years, 3 - 3.5 years, Baby Brains, Memory

I was writing a comment back to the few readers that responded to the last post, part of which mentioned autobiographical memory, and then realized it was WAY too long for a comment and I might as well share it with everyone. So, here are a few more thoughts about the research on autobiographical memory:

In the comment section, @sheila asked some GREAT questions, the first of which was: How do scientists measure memories and trace them forward to deem them accurate or not? There are a bunch of ways that developmental scientists look at these things, some will seem pretty darn boring because it's not like you can ASK an infant if he remembers something. So, what researchers do is, for example, show a baby a shape one day and then test whether he "remembers" it a few days later by looking at his gaze and the extent to which it implies "recognition". Or they will teach an 18 month old a sequence of play events (hit this, then this, then pop goes the toy) and then test him at 2 years old and see if he knows how to re-enact that play sequence. Ta DA! Memory! If you look at the article I linked to in the last post, they give you a bunch of details (if you can't access it and are interested enough, leave a comment and I can send the pdf file).

Sheila also described the common experience of not being able to differentiate details of your childhood memories from stories or pictures that parents and other people tell you as you are growing up. This is indeed the norm in terms of how most people think of childhood memories. Interestingly, and not surprisingly, children DEVELOP the ability to remember in different ways. At first, young babies and children tend to "encode" small, concrete details about their world. Of course, that's because that's how they understand the world around them at that early stage of cognitive development — in concrete terms, not abstract. Also, their working memory capacity (the RAM of our minds) is so limited at this age that they can't keep much in mind at the same time for very long at all. As children grow, they are able to hold more in storage, to keep more things in the mind's RAM for longer periods of time. With that developmental progression comes older children's and adults' abilities to encode more "gist-like" or "fuzzy trace" memories. So, we as adults are more likely to remember episodes in terms of their general meaning to us, their emotional valance, and so on. Both children and adults "store" memories in both the more literal (e.g., details about a task, episode, etc.) and "gist-like"  (semantic, elaborate, "relational) styles, but young children rely much more on the former and adults more on the latter. (You guys don't want me to spout on about the fact that there actually is no "storage" per se in the brain, like a treasure chest that gets opened and shut; instead it's more about patterns of neural firings that scientists are still pretty in the dark about).

@Beth wondered in the comments whether early memories can be triggered by trauma; implicitly I thought she was also asking if more traumatic experiences are better remembered. Yes, to have ANY experience stick and become a lasting memory, there needs to be SOME level of emotion involved. There's a whole lot of cool neuroscience to back this claim up — but the summary is that you need certain parts of your more "primal, emotional" brain to be firing during an event to encode it into long-term memory. So it is indeed possible that those more emotionally-charged experiences are the ones you remember best. But also, those are the experiences that will be talked about most in your family oftentimes, which keeps those memory traces alive and these re-enactments, in turn, continue to strengthen those neural memory traces.

But there is also the extreme cases of emotional memories; these are the cases of post-traumatic stress disorder (PTSD). People with PTSD have experienced INSANELY traumatic things (abuse, war, etc.) and in some of these cases, their emotional centres OVER-fired and shut down the part of the brain that participates in storing information and forming memories during the trauma. As a result of this emotional flooding, these people often DON'T remember the traumatic events themselves (nice evolutionary survival mechanism, if you ask me). PTSD sufferers often have NO semantic memory (they can't actually remember WHAT happened), but they have EMOTIONAL traces still "stored." So, for example, a loud bang from a garbage truck can trigger seemingly irrational panic/anxiety attacks in a veteran who has experienced horrors in combat, but he won't know why because he won't be able to trace the memory back to the initial experience. (For more info, Joseph LeDoux has some exceptional research in this area).

@Cloud expressed something I think about almost daily right now, as I try to develop family traditions that my children will hopefully look back on with warmth and love throughout their lives: How WEIRD is it that a 2.5 year old (and many 3-5 year olds also) won't remember our vacations, holiday celebrations, or any other cool events, events that they can NOW remember? I think it IS strange. But also, we have to remember (hahahahaha… ugh) that just because most children won't retain coherent memories of these special events into adulthood, they still MATTER. These experiences still make up the foundation of who our children are, how they are developing, how secure, happy, anxious, angry, and so on they WILL become. We may not be able to retrieve a perfectly intact memory of our childhood vacations (I certainly can't), but those experiences nevertheless were the basis from which we learned how to share with other kids, swim safely, dance like lunatics, trust adults, stay clear of poison ivy, read with a watch light under the covers, try different types of foods, and so on. 

And now this post is getting away from me and I haven't even BEGUN to talk about all the ways in which our memories are biased, flawed, skewed, motivated by our current situation, mood, developmental stage and so on. There are boatloads of studies that show how bad we are at ACCURATELY encoding certain types of information. And who among us has not had the fight with a parent, sibling or partner who remembered a CRUCIAL event totally differently than we did? Memory is NOT an objective, factual trace laid onto our neural circuitry… that's what makes it so fascinating for so many psychologists to study and for so many therapists to delve more deeply into with their clients.

Are those experiences that we CAN'T remember from our childhood any less influential on the person we've become than the things we DO remember? What memories would you be/ are you sad that your child will not retain? (My mother, for example, is horrified that I don't remember the details of our trip to Italy when we were 12 years old. TWELVE?!?! How could I forget that gorgeous cathedral, that ice cream cone, that gilded br
idge?! She thinks I'm brain damaged. But the thing is, I DO remember the guy on the Spanish Steps who winked at me on his moped… 28 years later, and I remember him and that wink PERFECTLY.)

– Isabela