Yes, you can digitize signals from plants using our free Spike Recorder software. You will get the signal saved in .wav format. Later you can import the .wav format to Matlab. Python or any other language where you will make your custom analysis. 

If you want to make a more quantitative comparison you can measure the length of the spike and amplitude in Spike Recorder.

Please take a look at section "Signal Measurements" in our manual:

If you are not interested in absolute measurements in mV but just relative measurements that you will use to compare the amplitude of spikes between experiments you can use RMS measurement in Spike Recorder.

If you select just a very short interval of the signal at the position of the peak of plant response spike Spike Recorder will display the RMS value of the signal at that point which you can use as a spike amplitude measure. Please take a look at the image in the attachment where we got the amplitude of spike as 15.553 (RMS is displayed in the bottom right corner).

Unfortunately, SpikerBox is not calibrated in volts. That is why we removed mV units from the vertical axis in most of the graphs in Spike Recorder. AD units of SpikerBox are linearly proportional to volts. 

Units can be expressed as C*V (volts multiplied by constant) where C is an unknown constant that should be determined by calibration of the device and V are volts. RMS has the same units as a signal.

Even though you do not know the actual value of constant C the measurements are very useful for expressing relative quantities like percentage of increase of signal activity and similar (since constant C will disappear from the equation when you divide two RMS values).

Currently, we are working on a simple procedure that will enable customers to calibrate their devices in volts. The calibration procedure will be incorporated in one of the next versions of Spike Recorder.