Follow up question to a post I saw a little bit ago. Since brainwaves are electromagnetic waves, I’m assuming in a similar way every day electricity is, would it be unreasonable to assume that these signals could be represented in logical 1/0 like we do for 5V/0V? And thus wouldn’t this help us map human brain functionality?
In: Biology
No it can’t really be represented by binary. To start with, it’s not electromagnetic waves. Our brains work by moving charged ions around, not using electromagnetic radiation, that’s just what the sensors use to read it.
Now onto why binary doesn’t work. There isn’t an “off” state like there is with binary. our neurons have a resting potential of around -70 mv. From here, negative and positive ions are added by tiny gates controlled by neurochemicals. This will either increase the voltage (making it easier for the neuron to fire) or lower the voltage (making it harder to fire). If the voltage manages to hit -55 mv, the neuron fires. This is a rapid increase in voltage to about 30 mv before rapidly dropping to around -80 mv. the resting voltage and the final voltage need to be variable and change. It’s fundamental to how neurons process information. The second drop to -80 mv is pretty important as well. On top of this, the amount of the chemicals released by the neuron isn’t constant and can change. So there isn’t one on or off state to be turned into binary.
There’s a few massive holdups to mapping brain functionality. The first is complexity. Our brains form a staggering amount of connections. Our brains have about 100 billion neurons. and a total of about 500 trillion connections are formed. you need to map out every single neuron and every single connection. If you mapped one a second, it would take about 15,854,896 years. Humans have only existed for about 200,000 years. A full mapping isn’t going to happen. We’ve mapped out the visual cortex of cats. That took decades and the people who did it got a nobel prize. Neurons are also incredibly small. If you look at an MRI of the brain, your not seeing individual neurons, not even close. You’re getting between a mm and 0.1 mm (at the extreme 100 hour scan end).
The second is ethics. As it turns out, mapping brain info is incredibly invasive and potentially dangerous. One of the ways we figure out what stuff does is by destroying the neurons. This is a no go with humans. Even with methods that don’t involve intentional brain damage, it’s still major surgery and you don’t really do that just to see how we work.
I think the problem with mapping brain activity accurately is density of signals. With so much in the way it’s hard to read them accurately especially through skulls
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