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by ItsMe000001 2917 days ago
But that's the beauty of the human brain: It knows what is needed and you are going to remember very quickly all those things - when you actually need them. So if you actually have people to coach you will learn and remember all those things effortlessly and almost without noticing it yourself, but when your brain detects no use for something to push something into it by brute force is a pain. It's one thing to learn the basics, it's another to fill your mind with specifics needlessly.

I once had an interview for a very well-paid freelancer position in a large company and could not answer the question "What is a right join?". It's not like I don't know that stuff - I do, but it's strange: there are many things like that, I actually know them, but I have to look them up. I only need 5 seconds then I remember everything. But when asked out of the blue I'm clueless. I was hired - and I became the guy they asked when a large Oracle query had to be constructed to look something up in the DB. Today, right now, I again only have a fuzzy notion of "right join" and would have to look up the details. I happily remove stuff from working memory that I don't need - but one 5-10 seconds look at one of thousands of webpages describing joins is all it takes to have that knowledge back in my working memory.

There are many things that I could not answer when asked out of the blue in an interview, and yet I would claim "I know that stuff". It's not a contradiction. For the last couple of years I've been learning new things like crazy, thanks to edX and Coursera and years of time off work to recover my health. Over 60 (finished) courses thus far, many of them topics I never had anything to do with before (medical mostly). I happily shift knowledge in and out all the time, I noticed how impossible - and useless - it is to keep anything in working memory for long. I'm not sure I could name all cranial nerves right now, and I took several neuroscience courses, they were some of my favorites. Yet I would claim that I know the, I just need a quick glance at a page about cranial nerves and it would all come back.

I'm not a walking Wikipedia, and those kinds of interviews are only useful to test what someone had to deal with in the time just before the interview. Sure, it weeds out clueless people - and a lot of good ones.

What a lot of people commenting on the interview topic also ignore is again that brains don't work like computers: context matters - extremely. We have studies showing that people think differently depending on whether they walk, sit in a small room or a large room, with the exact same task. Being in an interview is not just "stressful" - it's a very specific situation. It cannot just be compared to other merely stressful situations. You can do very well under stress - but not under interview stress. Interviews are, for one, somewhat adversarial. People around you try to find your weaknesses, they will get rid of you if you leave the wrong impression. Later on the job when it becomes stressful people work with you instead, everybody as a team towards the same goal. Not to mention that finding a job is not exactly easy no matter how low the unemployment rate. The kind of stress of an interview compares to nothing in ones actual work.

After the neuroscience courses, here is extremely rough my mental model to explain learning (based on my own interpretation of what I learned, this wasn't part of the curriculum way too fuzzy for actual neuroscience):

It's not like computer (or paper) storage that you fill with "knowledge" and then it sits there ready to be used by "the CPU" (which the brain is not, the computer model to explain the brain is completely off).

Instead, it's like paths through wilderness created by things repeatedly walking the same routes. When you learn you create paths. Literally. Strengthening/weakening of existing connections but also creating and abandoning synaptic connections. But the paths don't encode the concrete knowledge! What in our (computer-centric) models are concrete individual items in the brain becomes the result of signals traveling all over, and a concept we consider one item is the result of waves of signals going all over many paths in the brain, and not just once but with loops.

So when you learn something you don't learn the concrete knowledge like a computer does: "Now it's in memory and in the original form immediately accessible". In the brain it's something else. What created the "tracks" is gone but the tracks are still there! You don't have the original item you learned available, you instead have the path that it created. What exactly that means is not quite clear, but obviously you know something. That something, however, is not a static item of knowledge, it's something dynamic! It becomes useful when you use it.

What you cannot expect is that you put in concrete knowledge and at any later point get the exact same thing out. That's what we have books and computer storage for, the brain does not work like that. Nor should it! We developed those external tools to extend our brains, why are we trying to let our brains be like our tools? Yes, brains are much less predictable. Even from person to person, giving them the exact same knowledge creates different paths in each person's already different brain, and what you get out after feeding them the same input is even more different. Since we have become obsessed with creating predictable results we prefer testing in a way that would work better for how you would test a computer system.

I think something pretty much always overlooked is this: The brain does not attempt to encode the concepts that we talk about (such as "house", "tree", "friendship", "database"). It is the opposite. Our language attempts to represent the inside of our brains, in an approximation that depends on the goal and the context. For maximum confusion we then created new stuff within that externalized language system - and then try to put it back into the brain. There is nothing solid about it, it's all very dynamic and fuzzy. I see communication between humans more like trying to synchronize different dynamic systems. "Fire and forget" (send information and expect it to be understood) only works when there was a lot of prior synchronization. That means when new people meet in a new context (for at least one of them, in an interview) it will go more smoothly if they all share the same base synchronization, the same background - but that may actually be by accident. Out of tune communication partners might actually get better results after they "synchronize their waves". The "tuning" also is not between two fixed systems, both keep changing.

What I look for in new people is not how they are currently tuned but their "tunability", especially "auto-tunability". That means I care more about how much they do on their own to find things out. When an employee does experiments on their own, finds things out that nobody asked them about, digs deep into a problem without waiting to be told to do so - to me that's far more valuable than any amount of static knowledge.