If you spend enough time in a sensory deprivation tank, you will usually start experiencing abstract thoughts and sensory hallucinations. Dreaming is likely similar in that it's just the natural result of a few moving parts:
1. An eager sensory network with no inputs can introduce phantom inputs into the network, which can evolve through feedback loops in networks not being stimulated by real sensory phenomena
2. The brain and body's tendency to actively "simulate" its internal representation of the world, by creating mental scenarios and then playing them out.
When you throw a baseball, your CNS & muscles run simulations which adjust your motor neuron activation profile and the way your muscular cells function based on feedback from the brain about the success of the action.
When you practice a speech, you visualize the place you will be delivering it, visualize the audience and their potential reactions, so that you can plan accordingly. This is another kind of mental simulation.
Dreams might be the same thing, generating sensory feedback loops from brain activity resulting from memory organization and compression during the sleep cycle, simulating a world and then running through the simulation.
This can greatly increase an organism's survival if the organism's entire life revolves around finding food and avoiding predators / catching prey. While they are hidden and safely sleeping, animals are still able to "train" themselves completely unconsciously.
Seeing as how evolutionarily useful it is, I'm not surprised to see it crop up in multiple kinds of brains and would be very surprised if advanced aliens do not dream as well.
To me the question is if the octopus is subjectively experiencing the dream. I guess there's no reason to think it doesn't. Dogs definitely seem to dream and wake up scared shitless at times...cephalopods seem smarter than dogs.
The (very) amateur deep learning/ml developer in me wonders if these feedback loops in the brain are the key or something to the conundrum that backprop isn't neuromorphic (that we've found, last time I researched this)?
That is, everything is "feedforward" but the outputs sometimes are fed back to the inputs (both literally, and "figuratively" though physical means - ie, motor outputs move arms which the eyes see and turn back into sensory stimuli, etc)...
...I'm not naive enough to think that is an original thought, though.
The brains in almost all intelligent animals, from humans to crocodiles, evolved once. The most recent common ancestor of you and the average salamander had a brain that wasn't that much different than ours. It's not particularly surprising that both dogs and humans dream, because our most recent common ancestor was only a few tens of millions of years ago.
The most recent common ancestor between humans and octopuses was hundreds of millions of years ago. That ancestor wasn't dumb the way a frog is dumb, it was dumb the way a clam is dumb. It quite literally did not have a brain.
So yes, it's weird that both octopuses and the other branch of intelligent life both dream. That's interesting, and it tells us something about intelligence. If both birds and bats, who developed flight independently, both had sonar and bad vision, that would be interesting, and would tell us something about flight.
Probably that offline training is a significant boost to an intelligent creature's fitness function? (Where all mammals and quite a few other animals qualify as 'intelligent').
The more you can learn from that near-death experience without having another one, the less likely you are to become something's lunch.
soulofmischief|6 years ago
1. An eager sensory network with no inputs can introduce phantom inputs into the network, which can evolve through feedback loops in networks not being stimulated by real sensory phenomena
2. The brain and body's tendency to actively "simulate" its internal representation of the world, by creating mental scenarios and then playing them out.
When you throw a baseball, your CNS & muscles run simulations which adjust your motor neuron activation profile and the way your muscular cells function based on feedback from the brain about the success of the action.
When you practice a speech, you visualize the place you will be delivering it, visualize the audience and their potential reactions, so that you can plan accordingly. This is another kind of mental simulation.
Dreams might be the same thing, generating sensory feedback loops from brain activity resulting from memory organization and compression during the sleep cycle, simulating a world and then running through the simulation.
This can greatly increase an organism's survival if the organism's entire life revolves around finding food and avoiding predators / catching prey. While they are hidden and safely sleeping, animals are still able to "train" themselves completely unconsciously.
Seeing as how evolutionarily useful it is, I'm not surprised to see it crop up in multiple kinds of brains and would be very surprised if advanced aliens do not dream as well.
jcims|6 years ago
cr0sh|6 years ago
That is, everything is "feedforward" but the outputs sometimes are fed back to the inputs (both literally, and "figuratively" though physical means - ie, motor outputs move arms which the eyes see and turn back into sensory stimuli, etc)...
...I'm not naive enough to think that is an original thought, though.
Scapeghost|6 years ago
nwallin|6 years ago
The most recent common ancestor between humans and octopuses was hundreds of millions of years ago. That ancestor wasn't dumb the way a frog is dumb, it was dumb the way a clam is dumb. It quite literally did not have a brain.
So yes, it's weird that both octopuses and the other branch of intelligent life both dream. That's interesting, and it tells us something about intelligence. If both birds and bats, who developed flight independently, both had sonar and bad vision, that would be interesting, and would tell us something about flight.
taneq|6 years ago
The more you can learn from that near-death experience without having another one, the less likely you are to become something's lunch.
zacharycohn|6 years ago
albemuth|6 years ago