Attention level quantification during a modified stroop color word experiment: an fNIRS based study

Attention is one of the brain's ability to focus on one particular issue among many others. Attention plays a critical role in those tasks that involve detection of rare events such as air traffic control where any attention lapses may cause a disaster. So, measurement and quantification of attention workload levels is critical and can be used to improve one's performance. In this article an effective algorithm for measurement of one's attention in three different levels by means of functional near-infrared spectroscopy is presented. Brain hemodynamic of 8 healthy subjects during a modified stroop color word task over the PFC region is measured using a 4-channel continuous wave functional near infrared spectroscopy (fNIRS) instrument. Since the hemodynamic response of mental activities is contaminated by psychological inferences, the first processing step is extraction of evoked hemodynamic response due to various attention levels. Then, an effective feature of hemodynamic response is extracted and analyzed by ANOVA test. The results of this study demonstrate the feasibility of fNIRS based attention level measurement that could provide valuable information of individuals' ability.