Non-invasive NIR spectroscopy of human brain function during exercise

Near-Infrared Spectroscopy

“…However, Al-Rawi et al (2001) showed that the NIRO 300, a spatially resolved spectrometer, has a high degree of sensitivity and specificity to intracranial and extracranial changes. SRS is technically simpler than TRS and provides measurements with a good signal-to-noise ratio and a high time resolution (Perrey, 2008).…”

“…ICG is introduced rapidly and its rate of accumulation is measured over time. Blood flow can be measured as a ratio of ICG accumulated to the quantity of ICG introduced over a given time (Perrey, 2008). The accumulation of ICG in the brain will be dependent on both arterial inflow and venous outflow (Gora et al, 2002).…”

“…Second, there must be linearity and stability of the tracer dose response in tissue. Third, the tracer must not be metabolized or permanently retained in the tissue during the period of measurement (Perrey, 2008). And finally, the measurements should be made within the cerebrovascular transit time (four to six seconds), because then the venous outflow is negligible and the measured increase in cerebral ICG concentration can be assumed to be entirely the result of arterial inflow of the tracer.…”

Neurochemistry in the Pathophysiology of Septic Encephalopathy

“…Near infrared spectroscopy (NIRS) uses near infra-red region (800-2500nm) of light. Since the light in near infra -red range can pass through the skull, reach to the surface of the brain and coincide with the fast event-related responses in human recorded by electroencephalograms (Medvedev AV et al, 2010), it has been used to track cerebral hemodynamics (Gratton E et al, 2005) and human brain activity (Perrey S, 2008). On the other hand, trials to apply q-dots to the molecules associated with pathological states are performed in neurosurgery (Taghva A et al, 2010) and brain tumor (Popescu MA & Toms SA, 2006).…”

The role of the posterior parietal cortex in stereopsis and hand-eye coordination during motor task behaviours

“…Furthermore, cortical activation was investigated by means of the fNIRS neuroimaging technique. Compared to other neuroimaging techniques, fNIRS permits serial assessment of tasks in realistic environments in subjects performing complex dynamic movements (Perrey 2008). These characteristics make fNIRS a convenient modality for investigating cortical activation during complex tasks in MIS.…”