New fNIR functional near infrared optical imaging systems measure oxygen level changes in the prefrontal cortex of human subjects.

The fNIR system provides researchers with real-time monitoring of tissue oxygenation in the brain as subjects take tests, perform tasks, or receive stimulation. It allows researchers to quantitatively assess brain functions—such as attention, memory, planning, and problem solving—while individuals perform cognitive tasks.

fNIR is a powerful near-infrared spectroscopy imaging tool for in-lab cognitive tests. This technique measures NIR light absorbance in blood of hemoglobin with and without oxygen and provides information about ongoing brain activity similar to functional MRI studies. It eliminates many of the drawbacks of fMRI and provides a safe, affordable, noninvasive solution for cognitive function assessment. The technology empowers researchers by providing greater flexibility for study design, including working within complex lab environments and operating in non-traditional lab locations for field studies. The fNIR device provides relative change in hemoglobin levels, calculated using a modified Beer-Lambert law.

• Oxygenated hemoglobin change: delta O2Hb (µmol/L)
• Deoxygenated hemoglobin change: delta HHb (µmol/L)
• Total hemoglobin change: delta cHb (µmol/L)

fNIR data combines with physiological signals acquired through BIOPACs data acquisition and analysis systems such as ECG, respiration, cardiac output, blood pressure, electrodermal activity and stimulus response markers; AcqKnowledge software provides automated analysis tools for event related potentials and ensemble averaging. The system interfaces with most stimulus presentation systems (such as E-Prime or SuperLab) and BIOPAC's range of Virtual Reality systems.

Review fNIR Technology now to learn more (PDF) or read this comprehensive article:

Click for Journal of Visualized Experiments (JoVE) fNIR video and article PDF links.