Preceding article: How Do You Get to Carnegie Hall? Part One
NATURE AND NURTURE
I am a teacher by trade; my interest in the brain stems from trying to understand how we learn. I have tried to make my understanding of a complex and not thoroughly understood topic, clear and simple. All the mistakes are mine, but I am grateful to those who took the time to check it over and answer my questions while I was writing it. Readers who wish to pursue this subject should check out the books in my bibliography below.
This map of the brain suggests that specific and static areas are responsible for specific functions. In fact it is more complicated, less static and less specific than that. Image via Wikipedia
What is happening inside Emma’s brain and body? She was born with a good genetic mix. We can make that assumption because not only does she have smart, healthy parents but she is also a bright healthy baby who has hit all the milestones, except for size (she is on the small side), on time. As far as anyone can tell she has the tools she needs to learn and grow successfully.
A brief word about genetics and the brain: the current understanding is that the brain is too complex and the genetic code too limited to allow the brain to be directly blueprinted by genes. What is probably in the genetic blueprint is the timing of brain growth and which area is responsible for what. The rest is experience pruning and encouraging growth of synapses. (Schwartz 2002)
This is a fairly simplistic explanation of memory and learning. I should also note that there is considerable disagreement among the experts as to which does what where, when and sometimes how. With that caveat, you can see the difficulties a mere amateur faces.
Gross Motor Learning
Most of the learning I have been describing is called gross motor as Emma is largely using her big muscles. She learns through constant repetition of movement until both muscle and brain remember the movement. Both are needed to move her leg as undirected muscle, no matter how strong, is useless and skilled direction to the muscle without a trained muscle is, at the very least, frustrating. Each movement Emma makes is retained in the neocortex in an area that deals with gross motor movements and as she practices, it becomes more firmly embedded in her memory until she can do it without thinking about it. It is probable that the area storing this memory is not as specifically located as maps of the brain might lead us to believe. In fact, at this age the area may change day to day.
I am looking at two kinds of long-term memory here. (LeDoux 2002) One is the kind of memory we have of events. If we remember an event such as a birthday party, we remember through a number of sensory images such as smells, pictures, tastes, sounds and touches, and we remember them in the areas that originally received them. We patch them together (or blend them, depending on
Hippocampus Image via Wikipedia
the most recently accepted theory) through the hippocampus (among other areas of the brain) to create a memory of the birthday party. Neuroscientists call these kinds of event memories explicit or declarative memories. Others call it “knowing that” as in you know that red wine was spilt over your favourite cream shirt and the stain has never come out. Because we assemble declarative memories, they are seldom as accurate as we think or identical to those of other witnesses.
Most of Emma’s memories of learning to get her knee up on the level where she wants to climb are called implicit or non-declarative memories. (Walsh 2010) It might be easier to understand if you think of it as “knowing how” as in knowing how to ride a bicycle (which one apparently never forgets). These tend to be muscle memories, skill memories or memories which Emma will eventually recall and employ without consciously doing it. She probably isn’t conscious of most of her later efforts to get her knee up on a step any more than you remember specific incidents of lifting weights or steps in going for a walk. You will still strengthen your arms or your heart. She may remember specific attempts: the feel of the step under her knee and hands, the sound of her mother’s voice and the smell of detergent on her clothing. Those will be declarative memories.
Mapping and Practice: they’re brain changers
Emma’s constant practice does not just build muscle. It also changes her brain.
Motor Cortex Image via Wikipedia
Somewhere in the motor cortex, synapses have been alerted that this kid is into climbing and needs the brain involved more in the legs. The brain grows in the area of moving a leg onto a step because Emma is paying attention to what she is doing. It isn’t just that she exercises her muscles in a novel fashion but that she also gives it her attention as she learns how to do it. The growth Emma causes in the brain is called mapping. It takes very little attentive repetition to effect the mapping.
The Great Importance of Attention in Learning
Mapping is a little bit like the difference between driving (or cycling) somewhere yourself or sitting in a cab that is taking you there. If you are the driving force, you are more likely to remember. If you are sitting in a cab, looking out the window, you will find it harder to remember the route. The same is true as Emma gives attention to the skill of getting that leg up on a step and then pushing with her knee and her arms. She is the driver and she is not likely to forget this new skill.
That’s worth repeating: attentive exercise, in this case of the legs, will strengthen the legs and the area in the motor cortex that is involved with this movement of the legs. The difference is, and it is a big difference, the change in the brain requires Emma’s attention to what she is doing. (Schwartz 2002) This is only one small example of how Emma’s will and interaction with her environment shapes her brain. Even more interesting is that the brain will continue to be plastic enough to be shaped by her will throughout her life, although probably never as effectively as now:
The motor cortex …is hardly a static layout. From day to day and even moment to moment, the motor cortex map changes, reflecting the kind of movements it controls. Complex movements result in outputs from the motor cortex that strengthen some synapses and weaken others, producing enduring changes in synaptic strength that result in those things we call motor skills. Learning to ride a bicycle is possible, in likelihood, not merely because of something called muscle memory but also because of motor-cortex memory.(Schwartz 2002)
The Equal Importance of Practice in Learning
The non-declarative memories won’t do more mapping in the brain but will reinforce the mapping Emma has already laid down in her brain through her earlier attention to getting her knee on a step. She needs to do a lot of practice to get this skill into her implicit memory. Emma didn’t just climb the big steps outside. Her apartment is on the third floor and ever since she learned to climb steps, she has climbed the two stories to her home. A parent patiently walks behind ready to catch her if necessary but mainly chatting with Emma about what she is doing, what her trip to the park was like and what they will do when they get home. All that climbing has created strong arms, legs and strong implicit memory about climbing. None of this is special to Emma; every child maps new skills in the brain and reinforces the skill with practice.
Image via Wikipedia Click to see details of chart and sources.
Not all of this learning is just about gross motor movement and therefore intrinsic memory. Her parents deliberately teach Emma how to climb down safely. Teachers call it explicit teaching. The headfirst dive her mother caught her doing off the couch is not safe and so not acceptable. Emma is not allowed to
ever get down from a height without turning around and lowering her legs first. This practice will eventually end up in her muscle memory and in implicit memory. She will not think about how to get down safely; she will just do it. I suspect it gives her confidence as she learns because she knows her escape route.
Were her parents thinking this way? Probably not. More likely, they were thinking about making sure Emma knows how to be safe even when they aren’t watching. It is just as well, as who wants to think child–rearing from first principles?
When Emma is ready to move on, she builds on the implicit memory of putting her knee on the big outdoor step, by using her hands to pull herself up on that knee. She doesn’t learn to climb onto the baby gym and balance there immediately after standing. She learns to put a knee on a step, pull herself on the step and so on to each stage in the process. Usually when she starts a new stage, the previous stage has been mastered to the extent that it requires little or no thought, (i.e. it is in implicit memory) but the new stage will require her attention.
Emma’s ascent of the baby gym brings up the question of how much planning was involved. It’s hard to believe that she hadn’t thought about getting up there. The question is how long had she been thinking about it? Had she been thinking about it on and off for a couple of days, perhaps every time she saw it? Had she thought of it just that day or just before the attempt? Did she think about how she was going to get on it, or did she just attack it the way she attacks a big step or the couch? Did she get one knee and two hands firmly on the gym, balance, and then realise that getting the next knee up was going to be a bit tricky? These are questions worth answering. Have they have been answered? How could they be answered?
Whenever or however Emma planned her ascent, there must have been a point when Emma had to start thinking as well as doing. From the expression on her face, you can see the concentration that does not come from doing something learned and mastered. This is something new. Her concentration is fierce as she balances and brings the second knee to rest on the gym. When she is climbing steps, she will look around to see who is watching or taking a picture but this particular feat has all her attention and there is none left over for an audience. This feat will probably be in her explicit memory as it is the first time and she is very pleased with herself.
Many thanks to Dr. J. P. Thivierge and Dr. Vanessa Taler, both of the School of Psychology, University of Ottawa for suggesting books, clarifying concepts and reading these four posts for errors in neurology.
NEXT: NEGOTIATING LEARNING BETWEEN PARENTS AND CHILD
LeDoux, J. (2002). Synaptic Self; how our brains become who we are. London, England, Penguin Group.
Schwartz, J. M., Begley, Sharon (2002). The Mind & the Brain: Neuropasticity and the Power of Mental Force. New York, HarperCollins
Vygotsky, L. (1934/1986). Thought and Language. Cambridge Massachusetts, London England., MIT Press.
Walsh, S. J. (2010). Recognition Memory: Brain-Behaviour Relations from 0 to 3. Human Behaviour, Learning and the Developing Brain: Typical Development. D. F. Coch, Kurt W.; Dawson, Geraldine.