Biological Sciences 300, Smith College | Neurophysiology MetaNeuron Simulations of Membrane Potentials
About MetaNeuron	MetaNeuron, an application installed on our computers, simulates various aspects of membrane potentials in axons. Before class, read the introductory material on MetaNeuron simulation software, including the description of MetaNeuron's well-designed interface controls, and watch the video that demonstrates how to use the controls. Look through the rest of the instructions to see the activities you will do. Two help files are available on our website: Lesson Descriptions describes the six separate simulations ("lessons"), and Operating Instructions explains the controls.
Activities	We will run the first five simulations. Some will be demonstrations (quick dynamic observations of phenomena), while others will be detailed studies that may involve taking numerical data to plot. 1. Resting potential (demonstration) Observe the resting potential while changing the concentration of K+ in the outside saline. 2. Membrane time constant (demonstration) Decrease the membrane resistance and watch what happens as charges leak out across the membrane. Generate a train of stimulus pulses and observe "temporal integration." 3. Membrane length constant (demonstration) Estimate the length constant for the default conditions. Increase the axon diameter and observe changes in the spread of local circuit currents. Increase the membrane resistance and observe changes in the local circuit currents. 4. Axon action potential (detailed study) Explore the consequences of increasing and decreasing the stimulus amplitude. Take data to plot a stimulus strength-duration curve. Change the Na+ equilibrium potential to simulate a low sodium experiment. Run a twin pulse experiment to detect the refractory period. Examine conductances for Na+ and K+ in the twin-pulse experiment. Examine conductances while adjusting the amplitude of a single stimulus pulse. Vary the density of channels and observe the timing of spike initiation. 5. Axon voltage clamp (detailed study) Use your knowledge of the MetaNeuron simulation to explore voltage clamping.
At the end of class	Before leaving, gather the files and folders you created and place them in a new folder on the desktop. Label the folder with your team's names or initials.
	Graph paper for plotting strength-duration curve: