Method and system for detection of cognitive impairment

A method of determining brain activity in a user, the method comprising:

• receiving a user test input from a test device executing a stimulation test to the user;
• providing an optical input signal to a region of interest of the brain of the user via a head mounted sensor worn by the user,
• collecting optical response data from an optical detector in the region of interest;
• determining a hemoglobin level in the region of interest based on the optical response data;
• correlating the determined hemoglobin level in the region of interest with the user test input in response to the stimulation test;
• and
• evaluating brain activity based on the determined hemoglobin level.

A head mounted device for collecting data for evaluating brain activity in a patient, the device comprising:

• a blade structure having a curved shape operable for contact between the forehead and back of the head of a patient;
• a plurality of optodes in the blade structure, the plurality of optodes each including a dual-wavelength LED, a silicon photodiode and an optical fiber, wherein each of the plurality of optodes are located in proximity to a respective region of interest of the brain of the patient indicative of brain activity, the LED emitting an input signal to the respective region of interest, the silicon photodiode collecting a response optical signal from the respective region of interest;
• and
• a data interface collecting the response optical signals from the optical fibers of the optodes to determine hemoglobin levels of the respective regions of interest.