Artificial Consciousness/Neural Correlates/Neural Models/Activation Potential Model
The Action Potential Model
[edit | edit source]In the previous couple of sections we have discussed the input and output of the Data processing based model of the Neuron. In this section we need to consider the processing aspect of this model.
The Processing Element of the Data Processing model, sees each neuron as being a type of processor that conditions the data that it is presented, and outputs the conditioned result. How it processes the data, is the question that this model requires us to answer.
The action potential model, therefore describes how the voltage that is accumulated in the cell, is the result of the processing. In this model therefore it is the way that the voltage is changed that defines how the data is processed.
In the Data Processing Model, some of the processing is done in the dendritic mass, and some is done in the actual Soma of the cell where the signals are combined to form a single action potential. Once the signals have been integrated, then they are distributed by the Axon to other neurons. But what is the PROCESS that goes on within the cell?
In order to understand what processing is going on, we need to look not at the physical connections, but at the ways that the voltage is determined. The physical connections form something called a Wired OR structure, The inputs combine to form an output so every positive input adds to the output.
However the changes to the voltage of the cell are not always so simple to describe. For instance some ion channels produce negative inputs, and evidence from logic shows that negating a negative input, often results in something called DeMorganization in which a Wired OR function becomes a NAND function where a negative logic selection function becomes possible. As a result, the brain often works in a negative logic mode to select among signals.
If we however try to interpret the processing as only logical in nature, we find that our model no longer fits the reality, the function of even a three Neuro-Transmitter neuron is a super-set of logic where the function operates on a continuum between OR and NAND that includes functions that are not recognized by logic, if only because they are more inclusive or less inclusive than the classical logic functions could possibly be.
Some of the functions of ion channels are even more complex, because the ion channels themselves might be more complex. For instance some ion channels pump larger ions that have a stronger charge such as the chloride ion and have the result of blocking output of the cell, while other ion channels affect the inner function of the cell, and change the way it reacts to voltage. For instance the S synapse and the NMDA synapses both pump calcium into the cell which reduces Habituation.