Impaired prefrontal oxygenation during cognitive execution may serve as a diagnostic marker for psychiatric disorders such as major depression, schizophrenia, and bipolar disorders. Use the NIRSIT’s groundbreaking Optical Topography Report feature to now perform this objective evaluation. Current diagnosis of psychiatric disorders is mainly based on clinical interviews and structured clinical assessment based on Diagnostic Statistical Manual (DSM) or International Classification of Disease (ICD). There is evident need to explore alternate biomarkers to improve objectivity and accuracy of diagnosis. The NIRSIT tool provides a practical, cost-effective, and portable neuroimaging biomarker solution.
Several functional near-infrared spectroscopy (fNIRS) studies conducted on patients with Major Depressive Disorder (MDD) have shown a reduced increase in the oxygenated hemoglobin levels during a verbal fluency test (VFT). Oxygenated hemoglobin concentration has also been shown to be negatively correlated with the degree of Depression (Uemura 2014), with stronger correlation in recurrent cases (Wang 2017). Furthermore, association of prefrontal hemodynamic changes and suicidality has been demonstrated. Similarly, hemodynamics assessment during VFT has also shown to be valid in schizophrenia (Tran 2023) and bipolar disorders (Takizawa 2013).
The NIRSIT system provides a completely non-invasive neuroimaging solution. The evaluation can be performed in ordinary clinical settings and allows subjects to be comfortably seated in a well lit room. It has low maintenance costs. The unobtrusive design with no wires facilitates repeating the task (if needed) in this susceptible population. Further, the VFT task is easy to understand and execute. The entire assessment takes up to 5-10 minutes to perform, including set up.
The Optical Topography Report is personalized and generates a report that is easy to understand. The report automatically generates frontal and temporal lobe averages, displays Integral,Centroid, and Slope values, and the Centroid and Integral plot map. The Integral and the Central values capture the time-course changes that assist in making the final evaluation.