Relationship between salivary neuropeptide Y and performance under stress: a study on police firearms officers

Introduction: An emerging body of evidence suggests that plasma neuropeptide
Y (NPY) concentration is positively associated with performance under condi-
tions of psychological stress. However, whether NPY concentrations in saliva are
associated with performance under stress remains unknown.
Methods: We collected saliva samples in a high-performance environment and
tested the associations between salivary NPY, self-reported psychological vari-
ables, and performance during a stressful task. Participants were 15 male police
firearms officers (Mage = 33.57 years, SD
=
3.92) enrolled in a demanding selection
course. Participants provided their saliva samples using the passive drool method
1 h before the shooting task, which they needed to pass to remain on the course
(high-stress condition). Additionally, they provided a sample on a low-stress
training day (low-stress condition). Self-reported measures of psychological state
included measures of state anxiety (cognitive and somatic), self-confidence, and
threat appraisals provided 1 h prior to the shooting task.
Results and discussion: NPY concentrations were detected under both high- and
low-stress conditions. Mean NPY levels (ng/mL) were higher before the high-
stress shooting task (M = 1.56, SD = 0.88) than on the low-stress training day
(M = 1.13, SD = 0.52), but this difference did not reach significance. Salivary NPY
concentrations prior to the shooting task were positively and strongly associated
with shooting performance (n = 13, r = 0.71, p = 0.007). There were no associa-
tions between psychological variables and salivary NPY or shooting performance.
This study provides an important initial step in exploring the salivary NPY–per-
formance relationship. Further studies are needed to determine whether these
results can be replicated across different performance tasks and domains.