The provided code is designed to model neuronal behavior using the NEURON simulation environment. Specifically, it appears to focus on simulating the electrical activity of neurons, potentially drawing on the biophysical properties of specific cell types. Below are the key biological elements and processes represented in the code:
The code defines different types of neuron models using the functions makeWinoSat, makeWinNon, and makeWinNonIh. These functions instantiate cells which are likely variations of Winograd-type models:
Winograd Cells (WinoSat and WinNonS): These are likely to be based on variations of neuron models developed by Terry Winograd, which may include different synaptic inputs or channel properties.
Ionic Currents: The model references specific ionic currents through variables such as cai, representing intracellular calcium concentration, which is crucial for processes such as neurotransmitter release and synaptic plasticity.
Intracellular Calcium Concentration (cai): Calcium plays a pivotal role in neuronal signaling, synaptic plasticity, and other cellular processes. Tracking cai helps understand how action potentials and synaptic events can modify neuronal excitability and plasticity over time.
Action Potential Conductance (APC.rate): This likely refers to the rate of action potentials or the conductance responsible for generating or propagating action potentials, which are fundamental to neuronal communication.
Membrane Current (curr2.i): Represents various ion currents across the cell membrane, contributing to the membrane potential dynamics. This can include potassium, sodium, calcium, and other currents that are essential for initializing, propagating, and restoring the action potentials.
Temperature (h.celsius = 36): The model sets the temperature at 36°C, which is physiologically relevant, simulating near-body temperature conditions for mammals, ensuring that the kinetic properties of voltage-gated channels are accurately represented.
Initial Membrane Potential (h.v_init = -70): Default resting membrane potential is set at -70 millivolts, a typical resting potential for many neurons, setting the initial conditions for the neuron’s electrical state.
The code also incorporates graphing capabilities to visualize different aspects of the cellular model:
Voltage (p.soma.v) and specific currents or functions (p.soma.m_iar, p.soma.p1_iar): These graphs help visualize membrane potentials and the activity of specific ion channel states or ionic currents over time.
Graph Limits (time span of 66000 ms): The extended simulation time allows for the observation of neuronal dynamics over longer periods, essential for capturing phenomena like synaptic plasticity and long-term changes in neuronal excitability.
The code provides a framework for modeling the biophysical behavior of neurons by integrating essential components like ionic currents, membrane potentials, and channel gating, within the widely-used computational tool NEURON. The use of distinct models (Winograd variants) indicates an interest in exploring how different ionic properties and channel configurations affect neuronal activity.