Brain Waves, Associations, Forgetting
I think of brain waves as the process of "re-hashing" memes in the brain. A "meme" corresponds to a fantastically complex pattern [1] of activation of neurons. Activation of these patterns can be observed outside of the skull due to electrical side-effects of neuron "firing". I envision a looping chain reaction of memes, some at a very low level (hardly qualifying as memes), such as the sensation of breathing and some much higher, such as a friend speaking to you.
The wave frequency corresponds to the speed of "unpacking" one meme into another, or how fast one meme "reminds" you of another.
It's important to think of the brain as active and dynamic rather than a static container of "knowledge" and a "soul" sitting around inside the head observing he world. The looping never stops. When we are conscious (Beta waves, about 15 to 40 cycles per second - Herz). this looping is consciousness. As we think harder, the frequency of our Beta waves increases.
When we dream, these loops activate images in a chain of reactions we call dreaming.
In deep sleep, the loops fire neurons in a pattern that may seem random. Apparently, the object of he random firing is to dissolve or weaken connections between neurons. Connections that survive this process have been repeatedly activated and strengthened (neurons that fire together wire together). Pathways that are rarely used or used only once tend to be dissolved in his process as "irrelevant". These correspond to short term memories, such as the make and model of the car in front of you when you stopped at a traffic light yesterday.
On the other hand, the looping re-activation that occurs during conscious or dreaming states activates and reinforces associations between "higher level" memes. For example, you may dream of fixing your car or having an argument with your boss. The result is that memes will, in future, tend to cluster and "remind you" of each other.
During dreaming, the prefrontal cortex seems to be more or less "turned off", hinting that the corresponding function of that brain area is to dynamically involve itself in loops through the memes "stored" in the rest of the brain. The looping is more selective than it is during a dream. There seems to be a special kind of looping (waving) going on when we are awake.
[1] A bit of mathematical thinking: Imagine the state of the brain at any one time as a vector T in Hilbert Space. There is a component in this vector for each neuron: either 1 for "firing" or 0 for "not firing". Suppose further that there is a matrix S at any one time that characterizes the state of the synapses. It's a square matrix with rows and columns corresponding to T. Each element of the S (a,b) is 1 or 0 reflecting whether the synapse will conduct a signal from neuron a to b. At the next "instant", we will have a new brain state characterized by T' <= ST. S can change over time but more slowly, reflecting the levels of neurotransmitters in the brain. S says which neurons will receive an input signal when any neuron fires. What the neuron actually does with this signal can be complex but it boils down to firing or not firing. T will correspond to a large but finite number of memes. T' will correspond to a large but related set of memes. The rate that T' is generated from T corresponds to the frequency of the brain wave. For example, we may be "unpacking" memes to bring other memes to mind at a rate of 40 times a second when "thinking hard". This corresponds to a "frame rate" of 15 frames per second in a movie, hinting at why "thinking" may seem like a continuous process while ideas are actually "popping into our heads" at a finite but still fast rate of 40 times per second. "Alpha" waves, corresponding to deeper, more creative thought are coincidentally closer to movie frame rates of about 8 Hz, maybe allowing us to "picture" what we are thinking about.
This is not meant to be an actual model of the brain -- just a way of thinking about what's going on.
This model is based on something I built in 1969 to make a computer "think" about how "ideas" (programs) are related to each other. Each time around the wave, the computer "knew" which "ideas" were related to others in more and more indirect ways. This process can produce a relatively stable "S", in the sense that we can reinforce the association between memes simply by re-activating the association. The association becomes "natural" and "automatic", such as when you think of big ears and a trunk whenI say "elephant".
The wave frequency corresponds to the speed of "unpacking" one meme into another, or how fast one meme "reminds" you of another.
It's important to think of the brain as active and dynamic rather than a static container of "knowledge" and a "soul" sitting around inside the head observing he world. The looping never stops. When we are conscious (Beta waves, about 15 to 40 cycles per second - Herz). this looping is consciousness. As we think harder, the frequency of our Beta waves increases.
When we dream, these loops activate images in a chain of reactions we call dreaming.
In deep sleep, the loops fire neurons in a pattern that may seem random. Apparently, the object of he random firing is to dissolve or weaken connections between neurons. Connections that survive this process have been repeatedly activated and strengthened (neurons that fire together wire together). Pathways that are rarely used or used only once tend to be dissolved in his process as "irrelevant". These correspond to short term memories, such as the make and model of the car in front of you when you stopped at a traffic light yesterday.
On the other hand, the looping re-activation that occurs during conscious or dreaming states activates and reinforces associations between "higher level" memes. For example, you may dream of fixing your car or having an argument with your boss. The result is that memes will, in future, tend to cluster and "remind you" of each other.
During dreaming, the prefrontal cortex seems to be more or less "turned off", hinting that the corresponding function of that brain area is to dynamically involve itself in loops through the memes "stored" in the rest of the brain. The looping is more selective than it is during a dream. There seems to be a special kind of looping (waving) going on when we are awake.
[1] A bit of mathematical thinking: Imagine the state of the brain at any one time as a vector T in Hilbert Space. There is a component in this vector for each neuron: either 1 for "firing" or 0 for "not firing". Suppose further that there is a matrix S at any one time that characterizes the state of the synapses. It's a square matrix with rows and columns corresponding to T. Each element of the S (a,b) is 1 or 0 reflecting whether the synapse will conduct a signal from neuron a to b. At the next "instant", we will have a new brain state characterized by T' <= ST. S can change over time but more slowly, reflecting the levels of neurotransmitters in the brain. S says which neurons will receive an input signal when any neuron fires. What the neuron actually does with this signal can be complex but it boils down to firing or not firing. T will correspond to a large but finite number of memes. T' will correspond to a large but related set of memes. The rate that T' is generated from T corresponds to the frequency of the brain wave. For example, we may be "unpacking" memes to bring other memes to mind at a rate of 40 times a second when "thinking hard". This corresponds to a "frame rate" of 15 frames per second in a movie, hinting at why "thinking" may seem like a continuous process while ideas are actually "popping into our heads" at a finite but still fast rate of 40 times per second. "Alpha" waves, corresponding to deeper, more creative thought are coincidentally closer to movie frame rates of about 8 Hz, maybe allowing us to "picture" what we are thinking about.
This is not meant to be an actual model of the brain -- just a way of thinking about what's going on.
This model is based on something I built in 1969 to make a computer "think" about how "ideas" (programs) are related to each other. Each time around the wave, the computer "knew" which "ideas" were related to others in more and more indirect ways. This process can produce a relatively stable "S", in the sense that we can reinforce the association between memes simply by re-activating the association. The association becomes "natural" and "automatic", such as when you think of big ears and a trunk whenI say "elephant".
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