## 4 Discussion  
The purpose of this post-hoc analysis was to re-examine previously published data [15] to determine whether an individual's trait mood (long-standing predisposition to a mood) status contributed to inter-individual differences observed between acute consumption of a caffeinated beverage or a beverage containing similar caffeine content and adaptogenic herbs (e+shot) on neurocognitive outcomes. Our analysis suggests that TME, TPE, TMF, and TPF were uniquely modified by e+shot when compared to caffeine, with e+shot selectively benefiting individuals with low TPE or high TPF. However, e+shot, similar to the caffeinated placebo, only benefitted individuals characterized by high energy/low fatigue on fine motor task performance. Interestingly, subjects characterized by high TPE revealed a more significant decline in SBP after consuming the caffeinated placebo than after consuming the e+shot. Additionally, low TPF individuals had a higher HR after consuming the e+shot than after consuming the caffeinated placebo, while high TPF individuals responded with a lower HR after consuming the e+shot and a higher HR after consuming the caffeinated placebo. Overall, these results suggest that individuals experiencing typically low energy/high fatigue most benefitted from consuming both caffeine and adaptogenic herbs. The findings of this analysis are unique and leave very little comparable literature allowing us to examine previous findings more critically. For example, our initial publication [15] suggested no significant difference in anxiety among beverages. However, upon stratifying trait status, we now observed that caffeinated placebo increased anxiety in all participants. In contrast, those with low TPE reported significantly less increases in anxiety with the consumption of e+shot, whereas those with high TPE reported considerably more anxiety when consuming e+shot than caffeinated placebo. These results suggest that some individuals were resistant to the anxiety-provoking effects of caffeine when consuming e+shot. Indeed, anti-anxiety, anti-stress, anti-mental fatigue properties have long been ascribed to adaptogenic herbs [25]. In [PERSON] et al. [26], supplementation with rhoida for two weeks reduced anxiety in students characterized as mildly anxious (low trait anxiety) according to the Spielberger-State-Trait-Anxiety-Inventory. Our findings also suggest that TME, TPE, and TPF uniquely influence objective and subjective indices of mental energy and fatigue. For example, we report that individuals who are high TPF report the greatest benefits of e+shot on state mental fatigue, while individuals who are high TPE report the greatest benefit of consuming caffeine on the serial subtraction three task. Our findings may explain the inconsistent findings of studies assessing the effects of adaptogenic herbs on neurocognitive performance. For example, several adaptogenic herbs in e+shot, such as _Eleutherooccus senticosus, Rhodia rosea_, and Hawthorn (_Crataes avacantha_), have demonstrated clinical benefits on neurocognitive performance in many studies [26; 27; 28], whereas others have found no effects [29]. Mechanistically, one potential rationale for adaptogens' influence on psychosocial stress and neurocognitive measures could be via down-regulation of G-protein-coupled-receptor-signaling pathways, such as those modulating neurotransmitter activation and the HPA axis [30]. The potential benefits of adaptogenic herbs on many of these outcomes have recently been compiled by [PERSON] et al. [31], who also noted a potential rationale for the heterogeneity reported in the scientific literature. Another interesting finding is that we reported no significant differences between beverages on feelings of energy and fatigue [15]. However, our post-hoc analysis reports that e+shot effectively reduced feelings of mental and physical fatigue in high-TPF individuals compared to the caffeinated placebo.