MxN PRO High Definition transcranial Electrical Stimulator

Sub-gyri and multi-region targeting with image-guided neuronavigation.
Customizable waveforms in a range of independent stimulation channel options (5, 9, 17, 33, 65, and 128).
Full integration for closed-loop applications.

The first fully software-controlled stimulation system with unmatched specifications. The first stimulator that allows simultaneous multiple-region targeting. The first stimulator with sub-gyri targeting. The first stimulator with image-guided neuronavigation. A system so advanced, it could only have been made by Soterix Medical, the world leader in non-invasive neuromodulation and integrated imaging technologies.

Soterix Medical MxN-33 High Definition-transcranial Electrical Stimulator Soterix Medical MxN-33 High Definition-transcranial Electrical Stimulator Soterix Medical MxN-33 High Definition-transcranial Electrical Stimulator

The Soterix Medical MxN-PRO HD-tES / HD-tDCS stimulator allows fully programmable waveform control across up to 128 channels.
MRI-guided Neuronavigation combined with Neurotargeting software allows the selection of any superficial or deep brain target with unmatched control.
Full software control, including LSL (Lab Streaming Layer) integration. Seamless integration with behavioral tasks (E-Prime), imaging such as EEG and fNIRS, and synchronization with external devices.

Soterix Medical devices provide unique performance as these products, the methods of manufacturing are the subject to one or more U.S. or foreign patients or pending applications including but not limited to US9956395B2, US8818515B2, US8718778B2.

Simultaneous multiple-region targeting: The case for increased independent current-controlled channels

Soterix Medical MxN-33 High Definition-transcranial Electrical Stimulator

It is known that multiple brain regions and networks are involved in the pathogenesis of certain conditions, making it rational to optimize montages that allow simultaneous targeting of these regions. In fact, it has been shown that targeting as many as 5 brain regions requires ~30 electrodes (Huang 2018). Even when targeting just 2 brain regions, fully independent waveform (e.g. frequency) control optimizes neuromodulation (Reinhart and Nguyen 2019).

Targeting on five point-like ROIs (red circles in the MRI on left) or five brain structures (red regions in the MRI on right). Neurotargeting software prescribed optimal electrode placement and current per electrode (green topoplot-Montage colormap). The corresponding targeting result across 5 selected regions are shown on the right (brain false color, Electric Field colormap).

Sub-Gyri Targeting

The Soterix Medical MxN-PRO (formerly MxN-33) system is capable of Sub-Gyri targeting with arbitrary waveforms. Sub-Gyri current control integrates 3 unique Soterix Medical technologies:

  1. High-Definition (HD) tES to articulate current delivery
  2. MRI guided current flow using Neurotargeting
  3. Neuronavigated HD-MRI registration

Moreover, with current flow patterns produced by transcranial electrical stimulation modulated by cortex convolutions, and the resulting neuromodulation highly directionally sensitive, Soterix Medical created the only technology capable of sub-gyri specific control of electric field magnitude and direction (Rawji 2018)

Comparison of electric field modeling for montages directing current across and along the cortical surface. Study confirmed that orthogonal, but not parallel, oriented tDCS modulates TMS -MEPs. See Rawji 2018 for more information.

Broadest waveform range of any integrated system

MxN-33 Arbitrary Mode GUI

The Soterix Medical MxN-PRO (formerly MxN-33) allows generation of any waveform you want and through any electrode combination you want. The system allows simple selection from common waveforms (tDCS, tACS, tRNS) or loading customized arbitrary waveforms using sample values from a user-provided text file. The system will deliver any standard or arbitrary wave with a remarkable sample period of ~2 𝛍secs. This means no matter what waveform you choose, the MxN-PRO provides unmatched reliability and fidelity. The system supports Matlab integration to fully control stimulation and standard TTL triggers to start/abort stimulation (either generated by third party triggering solution or by our custom triggering interface), and can be configured to deliver complex protocols (deliver electrical stimulation at a certain delay from an event onset).

Integration with monitoring technologies

The Soterix Medical MxN-PRO Stimulator allows for the first time - dense stimulation (up to 65 channels) combined with dense recording applications. Leverage our integrated technology solutions to pair with research-grade EEG, fNIRS, PET, fMRI options that you want and trust. Use the full software control option to plan real-time closed-loop application. Use the triggering option to implement experiments that allow closing the loop. Use our unique electrode holders to hold HD-tES / HD-tDCS stimulation electrode and the recording electrode at the same scalp location by either: a) holding both at the same time or b) holding either one, one at a time. The possibilities are endless.

MxN-33 Brain Products EEG & MxN-33 Artinis fNIRS


Soterix Medical MxN-PRO systems can be used in the fMRI/MRI using a unique MxN-PRO-MRI kit. These complete kits provide an easy solution for full integration of our MxN-PRO stimulator with MRI/fMRI. The setup is rated to be compatible with any sequence in a 7T machine in Normal and First Level modes.

Soterix Medical Engineers have designed the MRI/fMRI accessories while keeping in mind the subject’s safety, stimulation tolerability, and the operator's ease-of-use. The unique setup uses filters through the patch panel for exceptional RF noise control, providing unmatched reliability. Learn more...

Unique Soterix Medical IFS-MRI kit

The MxN PRO system works in two modes

MxN-33 waveform interface GUI

Basic Mode

  • Program typical tES waveforms (tDCS, tACS, tRNS), intensity, duration, frequency (0.001 - 5KHz) where applicable, ramp time, and ramp occurrence.
  • Single channel selection- Same stimulation settings are applied automatically for all channels.
  • Multiple channel selection- Allows application of individual waveforms through selected channels.
  • Single or Double blind operation.

Arbitrary Mode

  • Load any waveform from samples in a text file with a sampling period of 2.5 μs and frequency as low as 0.001Hz.
  • Single channel selection- Same stimulation settings are applied automatically for all channels.
  • Multiple channel selection- Allows application of individual waveforms through selected channels.
  • Single or Double blind operation.

Performing behavioral research experiments?

Send E-prime triggers to start and stop MxN stimulation with millisecond accuracy with our dedicated Chronos Adapter.

Exclusive Validated System


  • Duration
    Adjustable from 3-7200 sec (1-sec resolution)
  • Frequency
    Adjustable from 0.001 to 5,000 Hz (0.001 Hz resolution)
  • Waveform load time (1 Channel)
    75 ms (arbitrary wave)
  • Sampling time (sample period)
    >5 μs (arbitrary wave)
  • Maximum number of samples
    128k samples for each channel
  • Waveform load time (32 Channels)
    2-20 ms (standard wave-DC, AC, etc.)