The OctaMon and OctaMon+ cerebral fNIRS packages, associated accessories, and software. The OctaMon (optimized for prefrontal measurements) and the OctaMon+ (applicable anywhere on the head) are ideal for capturing brain activity while having the freedom to perform daily activities including exercise. Like our other NIRS devices, the OctaMon measures changes in oxygenation in terms of oxyhemoglobin, deoxyhemoglobin, and total hemoglobin. These devices can be applied in a variety of dynamic settings often required in research, while still providing the high data quality required of a laboratory research grade device.