5 ms·

Why? What would that tell us about the computational complexity of a neuron?

by luc4sdreyer 5y ago

hall0ween 5y ago
To me, it seems like going up a layer in biological "abstraction"...
- JulianMorrison 5y ago
  Because the process that constructs a body part is only partially genetic, you'd be leaving out meaningful data. Mistaken idea: genes are like a program in code that defines what biology does. More accurate idea: genes are like the NVRAM of a running program that has run continuously with in-place updates for 4 billion years.
  - ianmcgowan 5y ago
    What an amazing comment, that just blew my mind. Talk about a paradigm shift.
  - spiralx 5y ago
    > More accurate idea: genes are like the NVRAM of a running program that has run continuously with in-place updates for 4 billion years. They also represent the NVRAM of the compiler that builds both the program and the compiler itself :)
- burnished 5y ago
  So, we know that human-like general intelligence is possible because we display it right? We're pretty sure it has something to do with that soft stuff inside our brain-baskets, and how that soft stuff is interconnected. We've found computational primitives that we call neurons, so the premise goes, if we can understand and copy how it works we can engineer intelligence. Right? So going to genetics, while interesting and worthy, isn't really going up a level of 'abstraction' because we're trying to get a systems level overview here. It is a process somewhat like studying a CPU by shocking prongs and occasionally slicing it real thin to see inside it.
kittiepryde 5y ago
It might give us an idea of how many types of models we would need to correspond to all genetically reasonable types of neurons. (my interpretation of the comment) For example, if there are like 8 free variables on neuron formation from the genetic blueprints, and then we find they produce reasonably different neuron types about 16 times over the range of that variable. We could end up with 4 billion possible models that we would need to simulate all possible neurons; then I guess you'd want to reduce those by saying that these two were like these other two and starting condensing them down; I'm not sure where this would go, but maybe we would find something cool or find a new insight by figuring out all possibilities
- causi 5y ago
  The difference between being able to describe a neuron's behavior and being able to simulate that behavior is the difference between being able to say "ten trillion trillion PN junctions" and being able to build a working computer that fits that description.
0-_-0 5y ago
This paper has found that you need 1000 artificial neurons to simulate a real one. This doesn't say much about the actual complexity of a neuron though, e.g. I'm sure you need many neurons to simulate a Fourier transform, even though the Fourier transform only has a few mathematical terms (in other words, the true complexity of a FT is much lower). What would tell us about its actual complexity though is if we knew how many "variables" the formula describing a single neuron has, which should be approximated by how many degrees of freedom in nature does its genetic description have.
- smegger001 5y ago
  i wonder if its the case that neurons are something of a Turing Tarpit doing something like implementing a Turing Machine but only using a limited number of operators other basic operation having to be implemented from the ones present (ie making a on XOR out of NAND gates for example) just highly optimized for a particular use-case.

Why? What would that tell us about the computational complexity of a neuron?

hall0ween 5y ago

To me, it seems like going up a layer in biological "abstraction"...

JulianMorrison 5y ago
Because the process that constructs a body part is only partially genetic, you'd be leaving out meaningful data. Mistaken idea: genes are like a program in code that defines what biology does. More accurate idea: genes are like the NVRAM of a running program that has run continuously with in-place updates for 4 billion years.
- ianmcgowan 5y ago
  What an amazing comment, that just blew my mind. Talk about a paradigm shift.
- spiralx 5y ago
  > More accurate idea: genes are like the NVRAM of a running program that has run continuously with in-place updates for 4 billion years. They also represent the NVRAM of the compiler that builds both the program and the compiler itself :)
burnished 5y ago
So, we know that human-like general intelligence is possible because we display it right? We're pretty sure it has something to do with that soft stuff inside our brain-baskets, and how that soft stuff is interconnected. We've found computational primitives that we call neurons, so the premise goes, if we can understand and copy how it works we can engineer intelligence. Right? So going to genetics, while interesting and worthy, isn't really going up a level of 'abstraction' because we're trying to get a systems level overview here. It is a process somewhat like studying a CPU by shocking prongs and occasionally slicing it real thin to see inside it.

kittiepryde 5y ago

It might give us an idea of how many types of models we would need to correspond to all genetically reasonable types of neurons. (my interpretation of the comment) For example, if there are like 8 free variables on neuron formation from the genetic blueprints, and then we find they produce reasonably different neuron types about 16 times over the range of that variable. We could end up with 4 billion possible models that we would need to simulate all possible neurons; then I guess you'd want to reduce those by saying that these two were like these other two and starting condensing them down; I'm not sure where this would go, but maybe we would find something cool or find a new insight by figuring out all possibilities

causi 5y ago
The difference between being able to describe a neuron's behavior and being able to simulate that behavior is the difference between being able to say "ten trillion trillion PN junctions" and being able to build a working computer that fits that description.

0-_-0 5y ago

This paper has found that you need 1000 artificial neurons to simulate a real one. This doesn't say much about the actual complexity of a neuron though, e.g. I'm sure you need many neurons to simulate a Fourier transform, even though the Fourier transform only has a few mathematical terms (in other words, the true complexity of a FT is much lower). What would tell us about its actual complexity though is if we knew how many "variables" the formula describing a single neuron has, which should be approximated by how many degrees of freedom in nature does its genetic description have.

smegger001 5y ago
i wonder if its the case that neurons are something of a Turing Tarpit doing something like implementing a Turing Machine but only using a limited number of operators other basic operation having to be implemented from the ones present (ie making a on XOR out of NAND gates for example) just highly optimized for a particular use-case.