offers a fully equipped, realistically appearing laboratory on the computer screen
to perform classical experiments with isolated nerve-muscle preparations of the frog.

All stimulation and recording parameters of the virtual devices are freely adjustable.
Mathematical algorithms guarantee for the appropriated reactions of the virtual muscle,
also considering the biological diversity of the preparations.
The virtual “SimMuscle” laboratory contains two nerve-muscle preparations and all the apparatus in a simplified but quite realistic form that you will need for experimentation.

For experimentation you first need to switch on all the devices (POWER buttons). Then drag one of two already prepared nerve-muscle preparations from the Petri-dish to hang it in the suspension apparatus which includes a mechano-electrical converter transforming changes of either the muscle force or muscle length, selectable by a toggle switch, into an electric potential. You can pre-stretch the muscle hanging one or more weights in the loop at which the muscle is fixed.

Muscle contractions are induced by current pulses delivered from a stimulation apparatus to the electrodes on which the nerve is placed. Stimuli as well as muscle contractions are displayed on a dual beam storage oscilloscope, appropriately displayed with accordingly adjusted voltage amplification and time base (via the rotary switches) and zero lines. Single or double pulses as well as trains of stimuli of selectable amplitude and intervals can be applied.

The example shows muscle contractions, here changes of the muscle length, in response to different trains of voltage pulses inducing isolated twitches, incomplete and complete tetanic contractions.

Featured experiments:

Single twitches and their stimulus dependencies (recruitement of motor units),
superposition of single twitches, tetanic contractions, resting tension curves (pre-stretching),
curves of isometric and isotonic maxima, muscle fatigue.
for details see Tutorial and Protocol form
For your own experiments you can download
a fully functioning DEMO Version