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

An emerging body of evidence suggests that plasma neuropeptide Y (NPY) concentration is positively associated with performance under conditions of psychological stress. However, whether NPY concentrations in saliva are associated with performance under stress remains unknown.

We collected saliva samples in a high-performance environment and tested the associations between salivary NPY, self-reported psychological variables, and performance during a stressful task. Participants were 15 male police firearms officers (M_age = 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.

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 associations between psychological variables and salivary NPY or shooting performance. This study provides an important initial step in exploring the salivary NPY-performance relationship. Further studies are needed to determine whether these results can be replicated across different performance tasks and domains.