- Poster presentation
- Open Access
Modeling of potentiation as cascaded gated processes; relevance to learning and seizure
BMC Neurosciencevolume 9, Article number: P65 (2008)
The neuron has elemental functionalities such as voltage-gated pores and allosterically-gated enzymes. Such functionalities are cascaded in the neuron resulting in complex functionalities. Such a functionality is potentiation. Potentiation is characterized by an excitation frequency/excitatory-postsynaptic-potential (EPSP) slope relationship. The basis of potentiation is thought to be the same as that of brain seizure and learning. I have reduced these gated elemental functionalities with the "Halfgate" device (fig 1). The behavior of the Halfgate is determined by several inputs. There is one output. The Halfgate-Set is a combination of sensors providing inputs to the Halfgate, an actuator receiving an output from the Halfgate and the Halfgate. The actuator modifies a single material in a single location. The "Den", which models biological potentiation, is composed of Halfgate-Sets mimicking concentration gated pores (See Fig 1). Long-term and short-term memories are embodied in the concentrations of solutes. The Den model exhibits frequency/slope behavior like that seen experimentally. In learning simulations, employing a monolayer of Den-based neurons, challenge-induced misfiring of incidental neurons was scored. Long-term memory was demonstrated: misfiring decreased regarding each successive session-start. Short-term memory was demonstrated: within a session misfiring was reduced. First session misfiring at start 50%, end <1%; second session start 3.2%, end <0.1%; third session start 1.8%, end <0.01%. Simulating recruitment in seizure initiation, specific high frequency patterns of excitation caused >0.1% of neurons to fire continuously. Model neurons containing subunits other than the Den are described. Models of experience-modified potentiation, and environmentally and electrically-modified seizure induction are detailed. Details are given of how microcontrollers can be used to produce task-general model brains composed of randomly interconnected neurons, which are comprised solely of cascaded gated pores.