(no subject)
I have spent the week watching Stuart Hameroff and Ramachandran lectures and the cortices are a'buzz with ideas of which I no longer have any ontological conception of.
The first part involves gamma synchrony. Gamma synchrony describes the simultaneous 40hz + frequency spikes recorded on EEG machines which have been found to be the most accurate neural correlate of consciousness. They dissapear during anaesthesia, they are correlated with the time and location of moments of awareness, such as when we become conceptually aware of a visual input.
Additionally, Gamma synchrony also seems to be linked with a state of "pure awareness", with increasing gamma frequencies as the interference from thalamocortical sensory disturbances decreases. For example, a study in which a group of Tibeten monks with 15+ years meditation experience and a group of college students with 2 days meditation training revealed that the monks had statistically far higher frequency readings than the college students during meditation. The gamma frequencies recorded in the brains of the monks ranged between 40 and 120hz, wheras in college students it was averaging at around 35 and rarely entering the gamma range.
Correlations have also found with psychoactive drugs that decrease the frequency range and those that increase it (Such as DMT and LSD). If gamma synchrony is the correlate of consciousness then the implication is that the frequency could represent the number of conscious moments per second. A user under the influence of opium for example, with a a low frequency range of 10 - 20 hz experiences time extremely quickly because he has far fewer conscious moments per second. However, a monk or trained sportsman experiences many more conscious moments in this time interval - explaining their extremely fast reaction speeds.
However, what is interesting is that classical synaptic Axon-Dentrite neurotransmission cannot explain Gamma synchrony. In classical neurotransmission, frequency spikes are sequential through time, one followed by another shortly aftewards due to the time taken for the neurotransmitter to cross the synapse and other processing. However, in gamma synchrony we have a simultaneous spike activity of the same frequency. This is suggestive that
a quantum process is at work because of the apparent simultaneous non-local effect. In our current scientific understanding, quantum entanglement is the only process that could explain such simultaneous action over a large network of neurons. Simple neurotransmission is not sufficient. So What Hameroff draws on is the fact that between neurons there are not only dendrite-axon neural networks but also lateral networks of hyperneurons linked by dendrite-dentrite gap-junction connections. This allows neurons to connect in such a away that they effectively form one huge neuron or continuous cytoplasm. This would also allow quantum affects to take place across neurons which normally would be impossible.
Within the cytoplasm next to the gap junction there are many thousands of microtubules. Microtubules are the long tubular structures used it mitosis-based cell division. They are composed of many small proteins called tubulin. Because of their unique structure(see Hameroff's lecture at the singularity summit for more details), the microtubules provide an isolated protected area that allows for the formation of coherent quantum states that would not normally be possible in a warm area such as the brain. Hameroff suggests that each tubulin protein acts as a quantum bit (qbit), and that each microtubule thus forms a microscopic quantum computer with an extremely large number of representational combinations. See Hameroff's lecture for images from his computer simulation that explains how the microtubules can be used for representation in more detail.
But how does this explain how concsciousness actually emerges? At the Plank scale, fundamental subunits of spacetime are believed to encode for physical properties such as mass and spin. Penrose suggests that in the same way, qualia are also represented by these spacetime patterns. Just as mass at its most basic level is represented in a data-like way, properties such as the experience of redness, sadness and pain are built into the universe as specific spacetime structures.
The links between microtubules across large scale dynamic nets of neurons provides a macroscopic environment for entanged particles which affect each other simultaneously. This would allow individual physico-qualia subunits to unite on a scale large enough to form a coherent quantum system which upon self collapse produces a unified conscious moment. But how ia this collapse goverened?
Hameroff explains that even an electron could have a conscious moment based on Penrose's pan-psychic explaination. But it would take ten billion years to have it due to the time taken to reach self collapse. and the intensity of the conscious moment would be extremely small. The larger the quantum system, the more unstable it becomes, and the faster it will collapse into a particular classical state. Hameroff calculated that average glia or hyperneurons would have a collapse time of between 25 and 100ms, which is consistent with the speed of other neuronal operations.
The model also offers an explaination for free will and decision making. The quantum states across the microtubules can be in large scale superposition utilizing millions of representational subunits - certainly enough to represent the content of multiple possible courses of action and the various reasons behind each. Once a particular state (choice) reaches the threshold for collapse, this choice becomes reality and activies all the normal processes of classical neuronal transmition to carry the action out.
Other evidence for this theory is based on the fact that general anaesthetics only bond with the proteins using quantum forces. (No chemical bonds are formed). Consciousness then dissapears while the anaesthetic acts, and only gamma activity dissapears from eeg readings.
Of course many questions remain. Particularly computational ones. How does classical transmission interaction with the system of microtubular representation? How do they cross talk? Why are the combinations of qubit representation seem meaningful to us? How does a collection of fundamental subunits in conjunction come to represent a concept like a tree?
I believe the evidence is very compelling, but the inner workings of the system needs detailed study at the microtubule level to make complete sense of it.
The first part involves gamma synchrony. Gamma synchrony describes the simultaneous 40hz + frequency spikes recorded on EEG machines which have been found to be the most accurate neural correlate of consciousness. They dissapear during anaesthesia, they are correlated with the time and location of moments of awareness, such as when we become conceptually aware of a visual input.
Additionally, Gamma synchrony also seems to be linked with a state of "pure awareness", with increasing gamma frequencies as the interference from thalamocortical sensory disturbances decreases. For example, a study in which a group of Tibeten monks with 15+ years meditation experience and a group of college students with 2 days meditation training revealed that the monks had statistically far higher frequency readings than the college students during meditation. The gamma frequencies recorded in the brains of the monks ranged between 40 and 120hz, wheras in college students it was averaging at around 35 and rarely entering the gamma range.
Correlations have also found with psychoactive drugs that decrease the frequency range and those that increase it (Such as DMT and LSD). If gamma synchrony is the correlate of consciousness then the implication is that the frequency could represent the number of conscious moments per second. A user under the influence of opium for example, with a a low frequency range of 10 - 20 hz experiences time extremely quickly because he has far fewer conscious moments per second. However, a monk or trained sportsman experiences many more conscious moments in this time interval - explaining their extremely fast reaction speeds.
However, what is interesting is that classical synaptic Axon-Dentrite neurotransmission cannot explain Gamma synchrony. In classical neurotransmission, frequency spikes are sequential through time, one followed by another shortly aftewards due to the time taken for the neurotransmitter to cross the synapse and other processing. However, in gamma synchrony we have a simultaneous spike activity of the same frequency. This is suggestive that
a quantum process is at work because of the apparent simultaneous non-local effect. In our current scientific understanding, quantum entanglement is the only process that could explain such simultaneous action over a large network of neurons. Simple neurotransmission is not sufficient. So What Hameroff draws on is the fact that between neurons there are not only dendrite-axon neural networks but also lateral networks of hyperneurons linked by dendrite-dentrite gap-junction connections. This allows neurons to connect in such a away that they effectively form one huge neuron or continuous cytoplasm. This would also allow quantum affects to take place across neurons which normally would be impossible.
Within the cytoplasm next to the gap junction there are many thousands of microtubules. Microtubules are the long tubular structures used it mitosis-based cell division. They are composed of many small proteins called tubulin. Because of their unique structure(see Hameroff's lecture at the singularity summit for more details), the microtubules provide an isolated protected area that allows for the formation of coherent quantum states that would not normally be possible in a warm area such as the brain. Hameroff suggests that each tubulin protein acts as a quantum bit (qbit), and that each microtubule thus forms a microscopic quantum computer with an extremely large number of representational combinations. See Hameroff's lecture for images from his computer simulation that explains how the microtubules can be used for representation in more detail.
But how does this explain how concsciousness actually emerges? At the Plank scale, fundamental subunits of spacetime are believed to encode for physical properties such as mass and spin. Penrose suggests that in the same way, qualia are also represented by these spacetime patterns. Just as mass at its most basic level is represented in a data-like way, properties such as the experience of redness, sadness and pain are built into the universe as specific spacetime structures.
The links between microtubules across large scale dynamic nets of neurons provides a macroscopic environment for entanged particles which affect each other simultaneously. This would allow individual physico-qualia subunits to unite on a scale large enough to form a coherent quantum system which upon self collapse produces a unified conscious moment. But how ia this collapse goverened?
Hameroff explains that even an electron could have a conscious moment based on Penrose's pan-psychic explaination. But it would take ten billion years to have it due to the time taken to reach self collapse. and the intensity of the conscious moment would be extremely small. The larger the quantum system, the more unstable it becomes, and the faster it will collapse into a particular classical state. Hameroff calculated that average glia or hyperneurons would have a collapse time of between 25 and 100ms, which is consistent with the speed of other neuronal operations.
The model also offers an explaination for free will and decision making. The quantum states across the microtubules can be in large scale superposition utilizing millions of representational subunits - certainly enough to represent the content of multiple possible courses of action and the various reasons behind each. Once a particular state (choice) reaches the threshold for collapse, this choice becomes reality and activies all the normal processes of classical neuronal transmition to carry the action out.
Other evidence for this theory is based on the fact that general anaesthetics only bond with the proteins using quantum forces. (No chemical bonds are formed). Consciousness then dissapears while the anaesthetic acts, and only gamma activity dissapears from eeg readings.
Of course many questions remain. Particularly computational ones. How does classical transmission interaction with the system of microtubular representation? How do they cross talk? Why are the combinations of qubit representation seem meaningful to us? How does a collection of fundamental subunits in conjunction come to represent a concept like a tree?
I believe the evidence is very compelling, but the inner workings of the system needs detailed study at the microtubule level to make complete sense of it.