Talking with Bill Nye the Science Guy is like meeting your favourite HS science teacher in a bar - the conversation might flail wildly, but you learn something at every twist. This week, I picked his brain about, well, brains.
Are there similarities between computer memory and human memory?
Everybody remembers numbers and computers remember numbers. People remember procedures and computers certainly remember procedures. But the other thing that's still important is that your perception as a human is affected subtly by all this stuff that you can't quite articulate. You run your life according to all this stuff that's happened to you. All of your memories affect everything you do whereas with a computer, there's adaptive software and things, but it's more literal.
So one of the significant differences between computers and people is the subconscious?
Yes. This business of "Drink Coke", the thing they would do in cinemas [in experiments back in the late 1950s] . On some level, that really works. Apparently it has to be an important image. The thing that gets the guys is, you show a naked woman for less than the time you can perceive it, so 1/16th of a second, or about 60 milliseconds. The next image a man is exposed to will be remembered better. If you're a hunter or if you're trying to make a decision when driving, you make that decision based on stuff that you can't quite perceive. So the quality of a computer memory is only as good as the instruments that are feeding it.
So what's special about how the human brain stores memory?
It's not how big your brain is. The significant thing is how well the brain is connected. Apparently there is redundancy in memory: You store the same memory in different parts of your brain for accessing at different speeds. That speed would depend on the frequency of use and the importance of the knowledge. If you have a memory, "A burner is hot; do not touch burner", you might store that in a few places to make sure you have it. It would be very strongly reinforced. Riding a bike is apparently very well fixed. But as the cerebellum degrades with age, so does the quality of those memories. The memories are there, but they're not as good.
You did an episode of your show covering addiction. What were the key brain issues there?
There are two really striking things. First, whether it's methamphetamines or alcohol or gambling where there's no chemical involved or drug involved at all, all the researchers are studying dopamine. Dopamine is this brain chemical that gets to your dopamine receptors and makes you happy. You start doing the addictive behaviour to feel good and then your receptors get overloaded with dopamine, then you stop doing the addictive thing and some of the receptors have shut down and you don't have enough dopamine to feel good. So then you feel bad and go back to the addictive behaviour to get more dopamine. The strange thing is that it works with what we think of as uppers and downers and whatever you call gambling - sidewaysers.
Are smartphones and Google going to take the place of our memory?
I don't think so. If you memorise the periodic table it will speed you up if you're a chemist, but by and large, the reason you have a periodic table is so that you can store that information outside of your body. That way it frees up some part of your brain to do something else, doesn't it? Intuitively you want some place [such as your phone]to store phone numbers, so you have that part of your brain to do other tasks.
So you're saying that even before the iPhone and Google and everything, we were offloading information?
That's what makes a human a human, if we store information outside our bodies. If you put a blaze on a trail, a stripe of paint or axe chop on a tree, it shows other humans where the trail is. It's storing information outside of your bodies. It's the hallmark of being a human. I mean, dogs and other animals mark trees - and I'm all for that - but it isn't quite the same.
So we're not going to get stupider as a result of using computers?
Boy, I don't think so. It's different skills. For example, I'm so old - here you might say, "How old are you?"
How old are you?
I am so old, I entered engineering school with a slide rule. And I left engineering school with a calculator. I can still use a slide rule but it's not a skill you especially need anymore. And you can go on and on about these kids today, they don't know where the decimal point is, back in my day ... Fine! But you don't really need to learn the slide rule. It's a cool thing, but a calculator is much better.
And now they have an iPhone instead of a TI-whatever.
So the first calculator that almost everybody could afford and had was the SR-50, Texas Instruments SR-50. Do you know what the SR meant? "Slide rule". It was as good as a slide rule, an SR-50. It was that good. I always say when you see that old black-and-white footage of the rocket on the launch pad and it falls over and explodes, that's because people had slide rules. Not having the decimal point is a real drawback. You want the decimal point, take it from me.
In geographical terms, GPS has done that too, right? People don't have to remember anymore.
The US Navy has several people on every ship that can navigate by the stars. They don't fool with that. Have you ever heard of the electro-magnetic pulse? The US Navy is very sensitive to this failure mode where people explode enough weapons high in the atmosphere and a significant fraction of the satellites are disabled. What are you going to do? You're a ship at sea in a trackless ocean. Cadets from the Naval Academy know how to navigate by the stars.
It almost makes me think of the book Dune and the mentats, the human computers.
Speaking of human computers, there is a guy named Art Benjamin, he's a human calculator. He says it's a skill he learned as a kid. Now he's a maths professor at Harvey Mudd. He can find the square root of a six digit number in a few seconds. Practice.
But is that skill less impressive to kids now because they have computers?
I don't know, I think it's pretty impressive. It might be more impressive because it might be that arithmetic is even further from a kid's everyday experience. I mean, how can you do it as fast as a machine? And I meet so many people who are intimidated by arithmetic.
Thanks to Bill, the one and only Science Guy, for a lively discussion that also touched on global warming, the irresponsible behaviour of Glenn Beck, why the internet may prevent another Hitler and how good salmon are at smelling. As always, you can catch his pearls of wisdom - and learn more about his war against ignorance - on his website.
Brain sketch by Patrick J. Lynch, medical illustrator, used under Creative Commons license
Thanks to Don for his transcription services