Is it possible to apply TBS on Rapid2 through MAGIC?

[pheart123]

Dear all,

We have tried using MAGIC for single pulse control and it worked very well.

However, we looked through the code (both rapid.m and magstim.m) and the documentation. There doesn't seem to be a way for setting burst mode (theta burst stimulation or TBS) and related parameters (e.g., inter-burst interval, pulse frequency within burst etc.) on Rapid2. We've tried to implement TBS with simple rTMS mode and use coding to control the interval between rTMS trains, but the interval for standard TBS sequence (roughly 200 ms) is shorter than the minimum wait time for Rapid Subclass.

Is there currently a way to implement TBS on Rapid2 through MAGIC?

[longevity-software]

The last that I knew, Magstim have not released the additional commands for theta burst control, it may be worth emailing them to see what their current stance is on providing these, as far as I know, most people who want theta burst, either use the Magstim UI, or provide trigger pulses externally at the theta burst intervals.

[umair-hassan]

Dear all,

We have not updated rapid code since a long time, please let us know if you have any update info regarding the burst and train control over rapid. Meanwhile have you tried looking through this in MagPy? There were some updated released in MagPy that might solve this issue for you.

Thank you,
Umair

[longfangithub]

@longevity-software I'm interested in using external trigger pulses to generate theta burst stimulation (TBS) on a Magstim device.
Specifically:
What third-party libraries (e.g. Python, etc.) did you use to generate the precise timing for theta burst patterns (50Hz bursts, 5Hz repetition)?
What additional hardware was required beyond the basic Magstim unit and a trigger source?
Any code examples or setup details would be very helpful. Thanks!

[pheart123]

Hi @longfangithub,

So we did eventually figure out how to trigger TBS on Rapid2 (sort of). I'll put it here just in case anyone still having the same need.

You should be able to do this if 1. you already knew how to externally trigger single pulse with MAGIC, and 2. the Rapid2 device (not sure about other models) you operate have built in TBS control.

Here's the method:

1. Navigate the panel menu as if you are using TBS the normal way (burst mode, setting parameters, all that). Once you're in the state where the coil is ready to be armed and fired, proceed to next step.
2. Disconnect the cable connecting the touch panel and the rest of device (while power still on).
3. Follow the MAGIC instructions to connect your computer to the device.
4. Assuming you have a connected Matlab rapid class named magstimObj, then run this script:

magstimObj.rTMSMode(true);
magstimObj.arm();
magstimObj.setAmplitudeA(50);
magstimObj.setTrain(struct("frequency",50,"nPulses",10,"duration",[]));

When magstimObj.fire(); called, the coil should generate a conventional iTBS burst train with 10 bursts, 50 hz intra-burst frequency.

Unfortunately, we couldn't figure out a way to control burst frequency (5 Hz one) through external control. You will have to set it manually on the touch panel before unplugging it.

Some caveats to consider before using it though:

1. It's obvious that this is not the intended way to control the device. Test it thouroughly before any serious experiments, especially if participants are involved.
2. In my experience, the device is not that reliable on higher intensity. Expect connection to drop, overheat, having weird behavior etc.

There's prabably a more reliable reverse engineering way of doing this (there's some, well, backalley tips), but this worked for my use case at least.
Hope this helps.