An increasing number of research applications require online access to EEG data streams. For example, when signal features of the EEG are used to trigger TMS (Transcranial Magnetic Stimulation) pulses, or where algorithms in BCI (Brain Computer Interface) applications are used to provide immediate response. For these applications, minimum latency and high accuracy become increasingly important.
With TurboLink, we now offer a solution to achieve exactly that: high accuracy and fast data access! TurboLink integrates with your actiCHamp (Plus) and BrainVision Recorder setup. It streams EEG data from the actiCHamp (Plus) via a User Datagram Protocol (UDP) to your preferred data client, which is doing the data processing. The Recorder PC is used to configure actiCHamp (Plus) through TurboLink and to monitor and/or record the data in the BrainVision File Format for validation or offline analysis. See the schematics of the setup visualized below.
Figure 1. Schematic diagram of the actiCHamp (Plus) and TurboLink setup with a data client and recording PC.
UPD is a minimal network protocol allowing IP-based communication between network members. If you look up “UDP” you may find key words like “unsecure” or “unreliable” associated with it. In comparison to other conventional communication protocols (like TCP) however, UDP is a much better choice for transferring a lot of data with a low latency. While UDP would not be an optimal choice for your connection to the internet, UDP is the right protocol for our application. UDP allows a high data throughput per second with a low latency, which makes it a perfect choice for transferring many channels at high sampling rates and low latency.
By establishing a direct and local network connection between TurboLink and your data client via UDP, we achieve a reliable sampling latency of under 1.5 ms with up to 160 EEG channels plus 8 additional AUX channels.
… and the perfect match for TurboLink. bossdevice RESEARCH is a real-time digital signal processor consisting of hardware and software algorithms. It is designed to read-in a real-time raw UDP data stream to continuously analyze EEG data and to detect patterns based on oscillations in different frequencies. When such a specific bio-signal pattern is detected, the device indicates this through a standard TTL output port. This enables a connected device to know with millisecond accuracy when a specific bio-signal pattern occurs.
bossdevice RESEARCH has already been used in 3 clinical studies and is installed in 26 research labs around the world. It is created by the Germany based company sync2brain, which was founded out of a technology transfer research project at the University of Tuebingen (Germany). The team strives to have an impact on neuroscience by enabling the study of large-scale dynamics of the human brain with easy-to-program real-time signal processing technology that reads a stream of EEG data and triggers stimulation during pre-defined oscillatory brain states. We encourage you to look at one of the first publications by Prof. Dr. Christoph Zrenner, Co-founder of sync2brain, where a predecessor of bossdevice RESEARCH was used.
Building up the setup is not rocket science! For the actiCHamp and TurboLink part we provide a Setup Poster with graphical instructions and easy steps to follow. sync2brain’s user manual website will guide you through all the steps needed to power up your bossdevice RESEARCH, as well as how to connect it to TurboLink. The device itself is programmed using Mathworks’s MATLAB® methods and functions utilizing Simulink add-ons. Don’t worry, the manual also includes a complete MATLAB® API documentation and even demo scripts enabling a quick and easy start.
TurboLink for actiCHamp and actiCHamp Plus is available now. We are very much looking forward to seeing TurboLink and bossdevice RESEARCH being used in your setups.