SimNerv©

offers a fully equipped, realistically appearing laboratory on the computer screen
to perform classical experiments of compound action potential recordings
from isolated preparations of the frog’s sciatic nerve.
All stimulation and recording parameters of the virtual devices are freely adjustable. Mathematical algorithms guarantee for the appropriated reactions of the virtual nerve, also considering the biological diversity of the preparations.
In the “SimNerv” laboratory you will find a stimulator, an oscilloscope, a recording chamber and a Petri dish with two already prepared nerves.

For your measurements take one of the nerves by mouse click out of the Petri-dish and place it on the electrodes in the recording chamber. The position of the electrodes can be changed and the temperature of the recording chamber can be adjusted. You can set a nerve ligature (fully reversible) using the thread.

The stimulator delivers voltage pulses to the stimulation electrodes. The stimulus is simultaneously displayed at channel 1 of the oscilloscope via a separate cable..AMPLITUDE and DURATION of the stimulus pulses can be adjusted as well as the DELAY between the onsets of two successive stimuli when TWIN pulses shall be applied (MODE). The POLARITY switch allows to invert the direction of the current flow, INVERT corresponds to an exchange of the stimulus electrode positions.

The simple double-beam storage oscilloscope displays the stimulus pulse (channel 1), simultaneously with the compound action potential (CAP, channel 2) measured as the potential difference between the two recording electrodes by means of a differential amplifier. The sensitivity of both oscilloscope channels (mV/DIV) as well as their common time-base (ms/DIV) can be adjusted via the rotary switches.

Featured experiments:

Stimulus-response curve: recruitment of nerve fibres on increasing stimulus amplitudes
Strength-duration curve, rheobase, chronaxy: the impact of stimulus duration
Refractory period and anode break potentials: physiological and clinical relevance of Na+-channel inactivation:
Conduction velocity and the effect of temperature changes
Recordings of bi- and mono-phasic action potentials using reversible nerve ligatures,
Demonstrating the clinically most relevant impact of appropriate electrode positions,
Understanding the difference between intra- and extracellular recordings.
for details see Tutorial and Protocol form
For your own experiments you can download
a fully functioning DEMO Version