Weekly Head Voices #212: Use it, or lose it

Well hello there folks, and welcome to the 212th edition of the Weekly Head Voices!

This one covers the two weeks from Monday December 7 to Sunday December 20, 2020. My end-of-year vacation started at some point during the period under investigation, so there’s not all that much to report here, except perhaps for a small philosophy message brought to you by the world of science.

Figure 1: View of the bridge over the mouth of the Steenbras River, taken from our anniversary hike up Steenbras Gorge to the Crystal Pools and back.

Figure 1: View of the bridge over the mouth of the Steenbras River, taken from our anniversary hike up Steenbras Gorge to the Crystal Pools and back.

My Advent of Code comes to an end

You might remember from WHV #211 that I was really enjoying the Advent of Code 2020.

As I hinted there, I was happy to reach my modest goal of the double digits (i.e. day 10).

On day 20 however (which is of course December 20), the puzzle took up so much of my time that I decided, with significant difficulty (remember these puzzles are like cat nip for nerds), to drop out.

It’s been great fun, and I learned so much nim in such a short period, but at some point one has to make the call whether the time cost is justified by the fun and the learning.

P.S. It took about two days to finally let go. :)

Use it, or lose it

I am currently reading the fascinating book Livewired: The Inside Story of the Ever-Changing Brain by neuro-scientist David Eagleman.

As you can probably deduce from the title, this book is about how the brain never stops rewiring itself.

Even now as you’re reading these words, your brain is making and breaking connections, and changing chemical balances, as it crunches through and sometimes integrates the ideas that are invoked by this weird trick we humans do, called speech, and the even weirder trick, called writing.

(Writing: Your retinae count the photons coming from the screen on which you’re reading this, construct patterns of darkness and light, convert those patterns to words, and then string together those words into living, breathing simulations of reality in your giant neural network.)

Besides functioning as an awe-inspiring exploration of the inner workings of the brain and the nervous system, also for me with a little bit of existing background, the book explains the phenomenon that inside the brain there is a never-ending struggle between brain regions, between neurons and between the thoughts that they store.

If you are blindfolded for a few days, your audio cortex will start annexing parts of your visual cortex. If you’re blindfolded for long enough (don’t do this), your visual cortex could be repurposed completely.

Neurons compete for incoming data, memories compete for neurons; it’s a continual fight for existence.

When a new, more important or more stressful memory arrives, it can push out, into eternal oblivion, an older, less interesting memory.

If an input data stream like sight or hearing stops, another strong input stream will take over those neurons. When you stop practising long division, or algebraic simplification, you’ll first start to get slower, and then later lose that ability.

Those neurons have been repurposed.

(The book posits a really interesting hypothesis for why humans dream so visually: Your eyes are closed for a large part of the day. Your visual cortex would take a beating every night, i.e. be taken over by other parts of your brain, if you didn’t use it so actively during dreaming every night.)

You can probably see where this is going.

In the brain, just like in the rest of your human physiology, efficiency is everything.

The moment you stop practising a certain function, like math, or absorbing technical documents, or programming, or driving, or running, or being kind, your system will start to try to repurpose as much as possible of the required subsystems for other functions that you are actively deploying.

In short: Use it, or lose it.

You’re going to have to keep on practising all of the things you find important until the day all of it stops for the last time.

This may seem quite harsh, but man, does it keep us honest.