fNIR Imaging System

The fNIR Imaging Systems from fNIR Devices offer a stand-alone, non-invasive solution for continuous functional near-infrared spectroscopy (fNIRS), enabling real-time monitoring of brain activity without the constraints of traditional imaging modalities like fMRI. Subjects can remain seated at a computer or engage in mobile tasks, making it ideal for naturalistic cognitive function assessments.

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fNIR Imaging System Models

• fNIR103S – Imaging System
  Includes the Imager 2000S control unit (supporting up to 54 optodes), fNIRSoft Pro & COBI Studio software, two sensor cables (RXFNIR-CBL2000L and RXFNIR-CBL2000R), and three 18-channel sensor pads.
• fNIR203S – Data Collection System
  Includes all components of the fNIR103S, plus a dedicated data collection computer and mobile caddy.
• fNIR303S – Data Collection & Stimulation System
  Includes all components of the fNIR103S, plus two 5-channel sensor pads, two 6-channel sensor pads, two computers, and a pole cart for advanced data acquisition and stimulus presentation.

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Technology Overview

fNIRS is an optical neuroimaging method that measures brain activity by detecting changes in blood oxygenation in the prefrontal cortex. The sensor band, which contains infrared light sources and detectors, is worn comfortably on the forehead. As the subject performs tasks, the system continuously captures real-time changes in oxy- and deoxy-hemoglobin levels, providing valuable insights into cognitive processes.

The Imager 2000S supports up to 54 channels for high-resolution, continuous NIR spectroscopy and includes:

• A control unit
• High-quality sensor arrays
• Software for real-time data acquisition and post-processing

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Multimodal Physiological Integration

fNIRS data can be seamlessly synchronized with other physiological measurements, such as:

• ECG
• Respiration
• Cardiac output
• Blood pressure
• Electrodermal activity
• Stimulus markers

When combined using AcqKnowledge software, researchers can perform advanced analyses like event-related potentials (ERPs) and ensemble averaging, enabling deeper insights into the subject’s physiological and cognitive states. Applications include:

• Cognitive workload and performance
• Neurorehabilitation
• Anesthesia depth monitoring
• Brain-computer interface (BCI) research

fNIRS integrates smoothly with BIOPAC’s virtual reality platforms and stimulus delivery tools.

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fNIRSoft Pro Edition

fNIRSoft (fS) Pro is a standalone software suite for acquisition, visualization, and advanced analysis of fNIRS data. Users can interact via a graphical user interface or automate tasks through scripting. Key features include:

• Signal Analysis Tools: Preprocessing and filtering of raw data
• Time Series Viewer: Visualize temporal dynamics of fNIRS signals
• Topographic Mapping: Create brain maps overlaid on anatomical images

fS Pro enhances the research workflow with extended functionality compared to the standard version, enabling advanced exploration of brain activation patterns.

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Synchronization with MP200 Systems

For experiments involving multiple physiological signals, fNIR Systems can be synchronized with BIOPAC’s MP200 Research System:

• TTL Trigger Output: The Imager 2000S control unit can emit TTL pulses marking the start/end of baselines and recording sessions.
• Trigger Integration: Use a BNC-to-BNC cable to connect the trigger output to BIOPAC’s STP100C Isolated Digital Interface Module and set AcqKnowledge to respond to external triggers.
• Digital Trigger Recording: Capture trigger events using a jumper cable connected between the TRIG port and one of the Digital I/O lines on the rear of the AMI100D or UIM100C interface modules.

This integration enables precise alignment of fNIRS data with other biosignals for high-quality, time-locked analyses.