SAHARA HYBRID

Yes. g.SAHARA Hybrid is designed to acquire EEG signals in dry mode without conductive gel. The conductive pins establish contact with the scalp through the participant’s hair, while the integrated active electronics amplify the signal close to the recording site.

Dry operation significantly reduces participant preparation and eliminates post-recording hair washing. It is particularly useful for rapid BCI experiments, demonstrations, teaching laboratories, repeated measurements, and studies in which short setup times are important.

As with other dry EEG technologies, signal quality depends on correct cap placement, sufficient electrode, scalp contact, the participant’s hair, movement, and environmental interference. Researchers should therefore check the signal and impedance or contact quality before starting the experiment. When greater recording stability is required, the same electrodes can be used with conductive gel.

Yes. This is the central advantage of the hybrid electrode design. Researchers can begin an experiment with a completely dry setup and add conductive gel through the electrode’s central opening when lower electrode–skin impedance or greater signal stability is needed.

The electrodes, cap, amplifier, and recording software do not need to be replaced when switching recording modes. Gel may also be applied only to selected recording sites rather than the entire montage. For example, researchers could record most channels dry while using gel at positions that show insufficient contact or are especially important for the experiment.

This makes g.SAHARA Hybrid suitable for laboratories that require fast preparation for some studies but more stable gel-assisted recordings for longer, movement-intensive, or technically demanding experiments.

g.SAHARA Hybrid can be used with the g.tec EEG acquisition ecosystem, including:

• g.HIamp for high-density and high-performance EEG and biosignal acquisition
• g.USBamp for compact, modular EEG and biosignal recording
• g.Nautilus configurations that support g.SAHARA Hybrid active electrodes

The required electrode connection and system configuration depend on the selected amplifier. Compatible active electrode interfaces connect the electrodes to g.HIamp or g.USBamp, while supported g.Nautilus systems integrate the electrodes into a wearable or wireless EEG configuration.

This allows labs to use the same electrode technology across stationary, portable, and wireless research setups.

Yes. Supported g.Nautilus PRO Flexible, g.Nautilus RESEARCH and g.Nautilus Multi-Purpose configurations can be equipped with g.SAHARA Hybrid electrodes. This combines dry or gel-assisted electrode contact with wireless EEG acquisition, making the system suitable for mobile neuroscience, real-world experiments, neurorehabilitation, and studies involving participant movement.

The exact number of channels, cap configuration, and electrode strand must be selected as part of the g.Nautilus system configuration. Not every g.Nautilus model or clinical configuration necessarily uses the same electrode technology, so the required setup should be specified when ordering.

Yes. g.SAHARA Hybrid can acquire the event-related potentials required for P300 Brain-Computer Interfaces. A P300 response is a time-locked positive potential that typically occurs approximately 300 milliseconds after a relevant or attended stimulus. Reliable acquisition therefore requires stable electrode contact, accurate event markers, appropriate filtering, and synchronized stimulus presentation.

Research comparing dry and conventional gel-based EEG recordings has shown that dry electrodes can capture the relevant EEG activity for P300 paradigms and produce comparable BCI classification performance under suitable recording conditions.

For P300 experiments, electrodes are commonly positioned over central and parietal areas, although the exact montage depends on the paradigm and analysis method. Gel-assisted operation can be used when particularly stable ERP recordings are required.

Yes. g.SAHARA Hybrid is suitable for steady-state visual evoked potential and code-modulated visual evoked potential BCIs. These paradigms detect frequency- or code-specific neural responses generated while a participant attends to a visual stimulus.

SSVEP and C-VEP signals are usually strongest over occipital and parieto-occipital regions. Correct placement and stable contact at these positions are therefore particularly important. Dry recording is often sufficient for short, controlled experiments. Gel can be added when movement, hair, insufficient contact, or low signal-to-noise ratio affects the recording.

Studies cited by g.tec indicate that dry electrodes can capture the relevant frequency ranges for SSVEP/C-VEP and achieve performance comparable to gel-based EEG under appropriate experimental conditions.

Yes, although the appropriate recording mode depends on the study. Dry electrodes are useful when fast preparation, repeated measurements, and participant convenience are the main priorities. For longer sessions, researchers must carefully maintain stable cap pressure and electrode contact because movement, perspiration, changes in posture, and gradual cap displacement can affect dry recordings.

For demanding long-duration experiments, gel can be added to reduce electrode-skin impedance and stabilize the contact. Because the electrode is active, the EEG signal is amplified close to the scalp, which helps reduce susceptibility to cable-related interference.

Participant comfort should also be assessed during extended sessions, particularly when using dry pins. Cap size, electrode positioning, hair characteristics, and the pressure applied at each recording site can influence both comfort and signal quality.

Yes. g.SAHARA Hybrid can be incorporated into combined EEG-fNIRS configurations using a compatible g.GAMMAcap and supported fNIRS hardware. The cap provides defined positions for EEG electrodes and optical sources and detectors, helping maintain reproducible sensor placement over regions such as the frontal or sensorimotor cortex.

EEG measures electrical neural activity with high temporal resolution, while fNIRS measures changes in oxygenated and deoxygenated haemoglobin associated with cortical haemodynamics. Recording both modalities can therefore provide complementary information about fast electrophysiological activity and slower haemodynamic responses.

The acquisition systems must be synchronized so that EEG, fNIRS, stimuli, and event markers share a consistent timing reference. Possible configurations include g.tec EEG amplifiers combined with g.SENSOR fNIRS or supported NIRx solutions. The exact cap layout and available EEG and fNIRS channel counts depend on the selected system.