Performance-Based Differences in Prefrontal Cortex Activation: Assessing Dynamic Marksmanship Performance Using Functional Near-Infrared Spectroscopy.

Introduction: Marksmanship is a fundamental skill for all servicemembers. However, the underlying neurophysiological differences in performance among marksmen remain unclear. Incorporating neurophysiological tracking such as functional near-infrared spectroscopy (fNIRS) may identify performance-based differences in prefrontal cortex (PFC) activation during dynamic marksmanship scenarios. This study examined cognitive load within the PFC during a simulated dynamic marksmanship scenario in non-proficient and proficient marksmen.

Methods: Twenty-four participants (12 men, 12 women) wore an fNIRS device over their forehead during a simulated stationary pistol marksmanship task (to determine proficiency status) and a dynamic shoot/no-shoot course of fire (COF) (to assess cognitive load). Relative concentrations of oxyhemoglobin (HbO2 ), deoxygenated hemoglobin (deoxygenated Hb), and total hemoglobin (total Hb) were tracked to quantify PFC activation differences in twelve proficient (=80% hit percentage) and twelve non-proficient (<80% hit percentage) marksmen.

Results: No difference in completion time was observed between groups during the dynamic COF (p=.34). However, non-proficient marksmen showed 26.3% higher HbO2 (p=.02) and 42.1% higher total Hb (p<.01) in the PFC compared to proficient marksmen.

Conclusion: Tracking PFC hemodynamic activity identified proficiency-based differences in cognitive load during a dynamic COF. Applying fNIRS during marksmanship-related tasks may be useful in developing stress resilience and mission readiness for servicemembers.