Design of a Suitable NIR System for Monitoring Hemodynamic Changes in the Brain Prefrontal Cortex

Near infrared systems (NIRS) are able to detect hemodynamic changes in the brain cortex and offer several advantages to be considered as a suitable technology to address problems in medicine. The objective of this work was to design a NIRS prototype for monitoring the dorsolateral prefrontal cortex activity related with tobacco addiction. An analysis of the needs of potential users helped us to establish the design of a device with a safe optoelectronic circuit mounted on an adaptable and portable chase (size of 7 cm x 7 cm x 4 cm and weight of 100 g). Our device is capable to acquire two signals (750 nm and 850 nm) continuously while a subject makes arithmetic tasks. Both signals follow a reliable behavior and are in agreement with the reports from the literature. A clinical protocol comparing non-smokers vs smoker subjects is in progress to validate the results of our device.