Brief user Manual for NAPS (Neuron
Action Potential Simulator)
V 1.0 Input
1) Open NAPS V 1.0 Input. The program will immediately ask the user for the name of the project. This information will be used to save the generated data (i.e. waveforms, channel location, noise level, and firing rates for each neuron).
2) Before clicking the “Run Program” button, enter the number of neurons that you would like to create and the sampling rate that the constructed voltage trace will be output on the DAC board. These controls are located in the red rectangular box on the front panel.
3) In the middle of the front panel are the slide bars used to design and modify the shape of each neuron’s voltage spike. Parameters which are labeled with a “1” control the shape of the first valley or dip in the voltage spike. Parameters labeled with a “2” control the width and height of the voltage spike’s peak, and parameters labeled with a “3” control the shape of the last third of the waveform. The user also has the ability to add noise to the waveform with the “waveform noise” slider. The distribution of waveforms created at a particular noise value can be viewed by flipping the “View Spike Distribution” switch in the red box. All of the changes the user makes to each neuron’s voltage spike can be viewed in a display above the input parameters.
4) The user must designate two other parameters before entering the waveform into the program, firing rate and channel location. Both of these controls are located in a gray box to the right of the slider bars controlling the waveform’s physical shape. Fill up the channels beginning from zero onward. The order which you enter the channels is irrelevant (i.e. 1-0-0 and 0-1-0 will produce the same output signal), but if the user only wants to output on four channels, do not begin entering channels at channel 25, etc.
5) Once a channel location and a firing rate have been entered for a neuron, click on the “Enter waveform parameters” button. There is a counter below this button, which indicates how many neurons have been entered.
6) After all the user specified neurons have been constructed, a dialog box will appear that will ask the user how many EEG channels to create. These EEG channels generate sinusoidal waveforms that mimic human electroencephalograms. If the user does not wish to create EEG channels, simply enter zero for the number of channels and the input program will end.
7) If the user wishes to create EEG channels, enter a non-zero, positive number of EEG channels to create. After specifying this value, another dialog box will appear asking how long (in seconds) EEG data should be produced. This value will be the same for each channel.
8) Once the # of EEG channels and recording time, a dialog box will appear asking how many “distinct time intervals” to divide the channel recording time? This parameter divides the recording time into blocks of time where the user specifies the EEG waveforms physical characteristics. For example, if the EEG recording time was set as 100 seconds and the user specified five distinct time intervals, five, 20 second blocks of time would be created where the user could specify the EEG waveforms characteristics. The user can specify the waveforms two characteristic frequencies and their standard deviations of the EEG signal in the dark blue box in the front panel. When the design of the EEG waveform for a particular time interval is complete, press the “Enter EEG parameters” button.
9) The procedure outlined in step 8 is repeated for each EEG channel that the user creates. There is a counter for the EEG channel being constructed as well as the time interval being constructed above the “Enter EEG parameters” button. When all EEG channels have been constructed the program will end.