ECOG TOOLBOX

The ECoG toolbox allows to run experiments to perform a functional mapping of the cortex with high-gamma activation signals. The big advantage of g.HIamp in combination with g.HIsys is that the high-gamma signal can be recorded up to 1 kHz because of the superb noise-floor of g.tec technology. Normally these high frequencies are hidden because of amplifier noise, but g.HIamp uses a very high oversampling of the EEG data that is performed in two co-processor in the unit to reach this goal.

g.HISYS BLOCK LIBRARY

g.HIsys comes with specialized blocks for biosignal analysis that are needed in many real-time experiments. The library contains blocks for plotting data, pre-processing (source derivation, Notch filter, cascading Notch filter, bandpass filter), transformation (Trigger, Cut Samples, Select Channels), feature extraction (Moving Average, ERD, FFT, Pre/Post PSD, Spectrogram, Significance Analysis), output signals through muscle activity (Spasticity Control, EOG Selection, EMG Selection Threshold) and a Binary Decoder.

FILTERS

The source derivation, notch filter, cascading notch filter, EEG/ECG BW filter and BP BW filter blocks allow you to remove artifacts from the data or to extract certain components.

INPUT/OUTPUT

The Marker block is for keyboard and mouse markers in Simulink. The block checks the system for keyboard and mouse events and generates markers accordingly. Multiple blocks can be used to look for different events. The Mouse Pointer block can generate cursor movements via Simulink, similar to mouse control.

EXPERIMENTS

The Paradigm Presenter allows you to run multi-modal paradigms with videos, audio, text, images and DIO with g.STIMbox.

EXAMPLES

Examples contains many ready-to-go Simulink models.

EMG/EOG

Spasticity Control allows you to check the EMG contraction level, EOG Selection allows you to control a device with eye-blinks and eye-movements, EMG Selection Threshold calculates the RMS and allows you to trigger on muscle movements, EMG Selection Calibration allows you to calibrate on certain muscle movements to generate triggers if the threshold is crossed and EMG 2D selection calibration allows 2D muscle control.

FEATURE EXTRACTION

Feature extraction blocks allows you to calculate the power spectrum, ERD, FFT, averages and to perform a significance analysis.

AUDIO/VIDEO PROCESSING

The Audio Stimulation block presents a set of pre-recorded sound files via a low-latency sound driver to create different types of audio stimulation. The sound files can be enabled using a given sound ID. The Audio Stream block outputs stereo CD quality sound to the standard speakers from Simulink. The Camera Synchronization block allows you to record videos together with biosignals.

SIGNAL QUALITY

The EEG Quality Check and EEG Quality Display  allow you to perform real-time artifact detection and to identify whether the data are clean during the experiment.

FILE IO

The Load Data Stream and Save Data Stream blocks are highly optimized for quickly streaming data, which is especially important for a high number of channels or high sampling rates (up to 38.4 kHz per channel). The blocks also allow you to define a maximum file size to avoid unnecessarily large data-sets.

VISUALIZATION

The Vector Scope allows you to visualize signal averages of multiple channels, the EP Scope can show EPs from target and non-target signals and perform a statistical analysis, the SCOPE is used to visualize raw biosignal data with markers and triggers and the Threshold Scope allows you to visualize biosignal data and manually define a triggering threshold. The Spectrum Rawdata Scope and Spectrogram Scope are used to visualize EPs and spectrum data. The 3D Visualization Bubble Scope allows to show activations of certain cortical areas, the 3D Interpolation Scope allows to map EPs/ERS to the head or cortex, the 3D Multi Interpolation Scope allows to show brain maps at specific time points and the 3D Data Quality Scope allows to show quality indicators like impedance on a head model.

SIMULATION

The Real Time Clock allows you to run the Simulink model without an amplifier connected and to simulate real-time behavior.

BATCH PROCESSING

The Automatic Batch Starter block allows to specify necessary off-line processing steps for a certain Simulink model. When the Simulink model is stopped, the processing is automatically performed.

SIGNAL MANIPULATION/TRANSFORMATION

The Select Channels blocks allows you to perform the signal processing steps on a sub-set of channels, the Cut Samples block is used for EPs to select a pre- and post-stimulus interval and the Trigger block allows you to select epochs for EPs. The Select Events block selects event codes from the incoming events. For each change of the incoming event code (from zero to a non-zero value), the event codes are compared to specified event codes for selection. The Binary Decoder converts data into binary format e.g. to generate trigger signals. The Sensor Adaptation block converts input data from a g.tec sensor (such as a temperature sensor, g.Sensor, GSR sensor and SpO2 sensor) into meaningful outputs corresponding to the sensor.

REMOTE DATA ACQUISITION

Acquire data from a remote g.NEEDaccess server.

LAB STREAMING LAYER

Use the LSL protocol to send data or to receive data.

TOOLBOXES

g.tec develops many toolboxes that run under g.HIsys. These toolboxes contain all real-time processing code and allow to interact with g.BSanalyze to calibrate BCI systems or to perform offline analysis.

CAMERA CAPTURE

The Camera Synchronization block allows you to record a video from a webcam in MATLAB/Simulink and to synchronize the video with the biosignal data. The synchronization is done using the video frame number, which is output from the Camera Synchronization block and saved with the biosignal data. The biosignals and video can be read with g.BSanalyze for offline analysis

3D VISUALIZATION AND BRAIN MAPPING

g.HIsys contains new 3D visualization scopes such as the Bubble Scope to map brain activation to certain electrodes. The Interplation Scope helps you to interpolate brain activation and to project it to the head or cortex. With the Multi Interpolation Scope you can easily show activation maps at certain time points. And finally, the Data Quality Scope allows you to map data quality parameters to the skull or the cortex such as impedance.

g.CUBE STIMULATION PLATFORM

The new g.CUBE is a multi-modal stimulation unit that allows you to get real-time control of auditory, vibro-tactile, FES, tDCS stimulation.

• Auditory stimulation: enables the auditory stimulation of the left and right ear and sends perfectly aligned triggers to the EEG processing for suberp AEPs and BAEPS.
• Vibro-tactile stimulation: enables the vibro-tactile stimulation of up to 7 locations on the body and sends perfectly aligned triggers to the EEG processing.
• 2 x FES stimulation: enables the bipolar, biphasic functional electrical stimulation with 2 bipolar channels on two locations (e.g. hand and leg).
• 2 x tDCS stimulation: enables the transcranial direct current stimulation with bipolar electrodes on two locations on the head (e.g. motor cortex and frontal cortex)

PHYSIO OBSERVER

The Physio Observer is a complete system to classify different states of a subject based on physiological parameters. The system contains all necessary components to quantify emotions, workload, physical tasks and many other things.

The Physio Observer works with many different sensors and electrodes to measure physiological and physical parameters of a subject, and can derive a wide variety of parameters from these signals. A key feature of the system is that it allows you to run experimental paradigms that are synchronized with physiological signals. The paradigms allow you to bring the subject into specific states of emotions, workload, memory tasks, etc., while all parameters are captured. These states can be chosen by the experimenter. Then, a classification algorithm is trained on these parameters during the different states and tries to discriminate them. Finally, the accuracy is calculated, which provides an objective measure of the quality of the classification. The Physio Observer works in real-time, and can therefore track the current state of a subject on-line. This information can be transmitted to other applications or devices, including real-time feedback systems.

The Physio Observer is able to measure ECG, EEG, EMG, GSR, respiration, temperature, acceleration and oxygen saturation with g.USBamp, g.HIamp, g.Nautilus. This biosignal data is transmitted via USB or wireless to the recording computer that is storing and visualizing the data for inspection.

The recording computer also controls the experimental paradigm that instructs the subject about different tasks (e.g. calculating). The real-time processing system extracts parameters from the biosignal data such as heart rate, heart rate variability, respiration rate, inhalation time, change rate of GSR, etc. and classifies the data. Finally, the classification result predicts the subject’s current state. This result is updated in real-time and can also be transmitted to other applications or the experimenter.

The experimental paradigms are presented by default on a computer screen that gives the instructions to the subject. You can also use a head-mounted device, a Virtual Reality system from g.tec, or a custom exoskeleton system. Furthermore, the system can work with eye- and movement-trackers, to give tone, electrical or tactile stimulation. A microphone can be connected to log subject responses.

The UDP Interface allows you to send the classification result, and the calculated parameters, to other applications to support real-time loops.