Page 18 - JSOM Summer 2025

control, working memory, and cognitive flexibility, which are TABLE 1 Participant Characteristics
essential components during lethal force scenarios. 25,26 Due to Group; mean (SD)*
its portability and ability to handle motion artifacts, fNIRS has Proficient Non-proficient
advantages as an operational marker of cognitive load during marksmen; marksmen;
dynamic lethal force marksmanship compared to other phys- Characteristic n=12 n=12
iological-based wearable sensors such as heart rate, 27,28 skin Sex
conductance, and electroencephalography. Thus, this study Male 8 4
30
29
examined the cognitive load of the PFC using fNIRS during a Female 4 8
simulated dynamic marksmanship scenario in non-proficient
and proficient marksmen. Age, y 27.3 (6.1) 23.3 (5.7)
Height, cm 163.4 (37.6) 171.2 (7.3)
Weight, kg 77.4 (25.4) 68.6 (11.0)
Methods BMI, kg/m 2 26.3 (3.6) † 23.4 (3.0)
Participants Resistance training, h/wk 4.3 (2.3) 3.2 (1.8)
Twenty-four healthy participants (12 men and 12 women) Aerobic (cardio) training, h/wk 2.5 (1.7) 3.3 (2.4)
participated in the study (Table 1). All participants were self- Marksmanship
reported novice marksmen (<5 hours of marksmanship prac- Stationary hit percentage 86.7 (7.8) † 42.5 (18.7)
tice per month) and demonstrated the fundamental knowledge Dynamic time to completion, s 141.9 (31.0) 163.8 (71.6)
and skillset to safely handle and discharge the inert pistol used
throughout the study. Additionally, all participants had normal *Unless otherwise specified.
Significantly greater at p<.05.
†
or corrected-to-normal vision and were free from any muscu-
loskeletal injuries or neuromuscular disorders that would limit It required participants to fire single shots upon 10 station-
their pistol handling. Prior to enrolling in the study, all partic- ary human-silhouette (E-1) targets, presented individually or
ipants gave informed consent, filled out a health history ques- in doublets across nine engagement scenarios. Each target
tionnaire, and verified that they abstained from alcohol and was projected at simulated distances ranging from 7–31 me-
caffeine consumption for 12 hours before the marksmanship ters, with an exposure time of five seconds per scenario and
testing. This study complied with the tenets of the Declara- a two-second shot delay between scenarios (Appendix A).
tion of Helsinki and was approved by the Institutional Review Overall marksmanship performance was assessed by quanti-
Board (2004812). fying the number of hits on target. If a participant hit eight
or more targets (≥80% hit percentage), they were allocated
The single-visit, within-subject design was used to assess the into a “proficient” marksmen group, which is a hit percentage
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feasibility of fNIRS applied to the PFC to assess proficien- rate between sharpshooter and expert level marksmen status.
cy-based differences in cognitive load during a simulated Alternatively, if a participant hit less than eight targets (<80%
close-quarters shoot/no-shoot marksmanship task (Figure 1). hit percentage) they were allocated into a “non-proficient”
The laboratory visit began with sensor placement of the fNIRS marksmen group (Figure 1). Participants did not receive spe-
equipment on the participant’s forehead, followed by an in- cific feedback regarding their overall performance and were
troduction to the marksmanship simulator and the inert pistol blinded to their group allocation.
used during the marksmanship tasks. During the familiariza-
tion period, each participant performed 5–10 practice shots Following the stationary marksmanship task, each participant
on a projected target displayed at 3.04m, which allowed the transitioned to a dynamic close-quarters shoot/no-shoot task
participants to become comfortable with the recoil of the inert that projected friendly and non-friendly human-silhouette tar-
pistol and served to calibrate their shot dispersion pattern to gets in randomized order (Figure 1). The dynamic nature of the
the marksmanship simulator. course simulated the participant moving through an office en-
vironment, while randomized friendly and non-friendly targets
Following the practice shots, each participant transitioned to a were projected onto the screen, either as stationary targets or
stationary marksmanship task used to quantify marksmanship targets that moved vertically or horizontally behind barriers.
proficiency. The stationary marksmanship task was adapted Each non-friendly target was randomized to be knocked down
from the U.S. Army Pistol Qualification Course Table IV. with 1–3 shots on target, and each non-friendly target had to
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FIGURE 1 Overview of study
protocol (Created in BioRender.
Smith, C. (2025)
https://BioRender.com/b0o86vt).

16 | JSOM Volume 25, Edition 2 / Summer 2025