Neural Pruning vs. Long-Term Potentiation

“The only use of knowledge of the past is to equip us for the present.”

Alfred North Whitehead (1861 – 1947)

Our brains are probably the most complicated part of our bodies. It literally runs everything from all our voluntary function to most of our involuntary function. Isn’t it crazy how the brain named itself? I always thought it was funny that the brain can think about itself but not understand how it works.

Well, we actually do understand a few things:

  • The brain is made up of neurons, cells that communicate with each other using electricity
  • Neurons communicate through small gaps called a synapses with various electrochemical neurotransmitters
  • We have specific synapse connections for each activity that we do
Synaptic Connection (2019) – Christopher S. Mukiibi
Inspired by True Events.

An interesting feature of these synaptic connections is that they slightly change depending on what we need to survive in our environment. The brain strengthens the synaptic connections we use often and tosses out the stuff we don’t use to give more processing power to the useful synaptic connections.

Our brain is kind of like a computer. It needs RAM to run all of the programs properly so it automatically deletes synaptic connections we haven’t used in a while. Our miraculous brain does this through two processes:

Neural Pruning – the process that our brain uses to “make space” for useful things by deleting the things that we don’t use often. This is why we forget things that we haven’t done in a while.

Long-Term Potentiation (LTP) – the process which our brain uses to strengthen synaptic connections that it considers useful. For example, putting your pants on is a useful skill since we do it every day. So our brains build strong connections for those synapses and putting our pants on in the morning is an effortless task. This is a large reason why we don’t have to think hard about how to put on our pants.

The more often we fire a pre-synaptic signal we decrease the amount needed to trigger the same post-synaptic response. This is fancy pseudoscience talk for the more we do something, the less effort it requires to do it again.

R is the ratio of the average electrochemical concentration of the pre-synaptic signal and the average electrochemical concentration of the post-synaptic response.

This is useful to know when studying things like math, science, or any class that seems like a lot of effort to understand at first. Yes, it takes tremendous effort to fire your chemical electric signals when you first try something. But it does get easier as the post-synaptic ratio gets bigger.

R decreases over time. It starts at a value of 1 and infinitely approaches the asymptote Y= 0

Assuming consistent practice the R value should decrease over time and the synaptic connection should be giving off a much stronger response than the signal.

So what does this all mean for students?

It means that all of the new skills and information that we will be learning will seem difficult at first, but you can trust that if we keep practicing then it will get easier. However, if we stop practicing, then our brain will dump the old stuff to make room for the new stuff. We have to use our minds often and use them consistently or we’ll end up with 3 pounds of useless grey matter in our skulls.