Abstract:
Many neuron models exist, but usually the voltage is the central feature of those models. Recently interest in long-term potentiation (LTP) has surged, due to the fact that it is linked to learning. It has been shown that LTP is accompanied by an increase of the internal calcium concentration. Thus models with variable calcium concentration have been proposed. Since the calcium concentration is very low, this has a negligible effect on the membrane potential. In the present model all ion concentrations are variable due to ionic current and due to ion pumps. It is shown that this significantly increases the complexity of neural processing, and thus variable ion concentrations cannot be ignored in neurons with high firing frequency, or with very long depolarizations.
