In order to create an effective stimulation experiment, two main components are necessary – the stimulator software and and stimulator hardware module. Let’s briefly examine how they work together.
The Stimulator setup window in AcqKnowledge Software is an onscreen toolbox used for constructing the stimulus waveform type, shape, duration, repetition, and displays a graphical representation of the stimulus type being presented. It also controls how often the stimulus starts and stops within the software. These controls extend to cleverly being able to output two different stimulus types simultaneously, such as a pulse in one channel and a tone in the other. It is bascially the canvas upon which the stimulation paradigm is created, and provides a blueprint for the output.
But without the stimulator hardware, these sophisticated setups are merely waveforms on a screen. In order to control the intensity or voltage level of the stimulation signal and output it to a participant, it’s necessary to incorporate simulator hardware, such as the STM100C stimulator module.
The STM100C, which connects directly to the BIOPAC MP160 System, has a number of controls for outputting and interacting with the stimulation signal generated by the software, the main one of which is the level control on the front panel. This enables you to increase or decrease the amplitude or intensity on the software stimulation waveform, and whereas the waveform shape will remain unaltered, the power of the pulse can be attenuated as desired. The STM100C can also interface with headphones (for audio stimulus), LEDs, and other devices. The STM100C module itself is not powerful enough to generate much voltage on its own, so to provide the desired voltage or current range for nerve conduction studies, an isolation adapter is required. Think of these adapters as small amplifiers that multiply the STM100C voltage or current output to the proper levels needed for the study. Isolation adapters plug directly into the STM100C unit, and the electrodes connected to the participant interface to the isolation adapters. Additionally, a monitoring cable can also be connected so the voltage or current output can be viewed onscreen in AcqKnowledge.
We also invite you to view a free webinar on various stimulation techniques using BIOPAC hardware and software.
BIOPAC offers a wide array of wired and wireless equipment that can be used in your research. To find more information on solutions for recording and analyzing signals such as ECG, heart rate, respiration and more using any platforms mentioned in this blog post, you can visit the individual application pages on the BIOPAC website.