TRIGBOX

Yes. g.TRIGbox can generate hardware triggers from visual changes detected by optical sensors, independently of the software used to display the stimuli. Researchers can therefore build visual stimulation paradigms using software such as PowerPoint without requiring MATLAB to generate the trigger signals.

For example, optical sensors can detect target and non-target visual events during a P300 experiment. Their trigger signals can be recorded with EEG data using g.HIamp and g.Recorder, supporting real-time ERP averaging, topographic visualization, and analysis of stimulus-related brain responses.

Yes. g.TRIGbox provides 4 kV electrical isolation between its input and output lines, helping electrically separate external stimulus detection equipment from the EEG acquisition system.

The device can operate from a 9 V alkaline battery or an optional approved safety power supply. Third-party power supplies or chargers should not be substituted without manufacturer approval. g.TRIGbox is intended for scientific research and is not a certified medical device.

Yes. The four independent input channels can detect events from different external stimulation sources, such as a visual display, audio system, response button, or piezoelectric sensor. Each channel can be adjusted independently to detect its respective signal reliably.

This makes g.TRIGbox suitable for multimodal EEG, ERP, and BCI research, where events from different stimulus modalities need to be recorded in a common acquisition timeline. g.TRIGbox detects and marks external events; it does not itself generate or control the stimulation paradigms.

g.TRIGbox supports three input categories per trigger channel:

• Low-level analog inputs: ±0.5 mV to ±200 mV, suitable for signals from dynamic microphones, inductive sensors, piezoelectric sensors, and compatible audio outputs.
• High-level inputs: ±100 mV to ±5 V, including compatible pushbuttons and TTL/CMOS signals.
• Optical inputs: High-speed phototransistor sensors for detecting changes in light intensity.

Trigger outputs are available as 5 V TTL/CMOS signals and 200 mV analog signals, including individual and encoded output formats.

g.TRIGbox provides four independent trigger channels, each supporting low-level analog, high-level analog/digital, and optical input types. Each channel has an individually adjustable detection threshold and LED indicator.

In addition to individual trigger outputs, g.TRIGbox provides a 4-bit encoded analog output representing 16 possible combinations of the four trigger states. This allows multiple event combinations to be represented through a single compatible analog acquisition channel.

Yes, g.TRIGbox can be used in experiments involving these software environments because its trigger detection operates independently of the stimulus presentation software. It detects compatible physical optical, analog, or digital signals rather than requiring a software-specific interface.

For example, an optical sensor can detect a visual change generated by a PsychoPy or MATLAB paradigm and produce a hardware trigger. g.TRIGbox does not require a dedicated MATLAB toolbox, Python API, USB connection, or software driver for its documented trigger detection functions.

g.TRIGbox generates bounce-free trigger pulses with a minimum output duration of 20 ms to support detection even at relatively low acquisition sampling rates. However, this pulse duration must not be confused with trigger latency or timing jitter.

The published technical documentation does not specify a numerical stimulus-to-trigger delay, timing jitter, or synchronization accuracy in microseconds. Researchers requiring quantified timing performance for their experimental protocols should request validated measurements from g.tec.

Yes. g.TRIGbox supports high-speed optical phototransistor sensors that detect physical changes in light intensity on a display. This allows researchers to generate trigger events from actual visual stimulus changes rather than solely from software commands. This approach is particularly useful in visual ERP, P300, and VEP experiments, where the difference between a software event and the displayed stimulus can affect event alignment.

g.TRIGbox is designed for integration with g.HIamp, g.USBamp, and g.Nautilus EEG acquisition systems using a compatible trigger cable adapter. It provides individual 5 V TTL and 200 mV analog trigger outputs, as well as encoded outputs, through a 15-pin D-Sub connector. Integration with third-party EEG systems is possible when their electrical input specifications and connector requirements are compatible.

The g.TRIGbox is a multimodal hardware trigger detection interface that converts external stimulus events into bounce-free electrical trigger pulses. It detects optical changes on screens, audio signals, piezoelectric and inductive sensor signals, pushbutton events, and digital inputs. These pulses can be recorded alongside EEG data to identify when an external event occurred. Four independent trigger channels allow researchers to capture multiple event sources within a single experimental setup.