## Results
### MANT Response Time  
The omnibus analysis revealed a significant main effect of intervention (F(1397) = 5.96, \(p\) < 0.001) with participants in the berry condition responding faster than placebo along with a main effect of session (F(2400) = 5.96, \(p\) = 0.003). As can be seen in Figure 4, post hoc analysis revealed significantly faster performance following the berry intervention in comparison to placebo at 2 h (\(p\) = 0.006) and 4 h (\(p\) = 0.001) with a further trend for faster berry performance at 6 h (\(p\) = 0.068); furthermore significantly faster response times were seen at 4 h in comparison to 2 h for the Berry intervention (\(p\) = 0.021) whilst the placebo trended towards significance for the same time period (\(p\) = 0.051).  
The main effect of intervention was qualified by intervention x congruency (F(2408) = 48.0, \(p\) < 0.001] and intervention x load (F(2398) = 3.23, \(p\) = 0.041) interactions. For the intervention x congruency interaction, post-hoc analysis revealed faster response times for the berry intervention in comparison to placebo for incongruent trials (\(p\) = 0.047) and neutral trials (\(p\) = 0.022). Specifically, on neutral trials significantly faster response times for the berry intervention, in comparison to placebo, were seen at 2 h (\(p\) = 0.031) and 4 h (\(p\) = 0.030), whilst for incongruent trials significantly faster berry-induced responses were seen at 4 h only (\(p\) = 0.007). There was also trend for faster berry response times in comparison to the placebo on congruent trials seen at 2 h (\(p\) = 0.087). Furthermore, there were significantly slower response times for the placebo condition on congruent trials at 4 h in comparison to 2 h (\(p\) = 0.021) whilst speed of berry performance was maintained between these sessions.  
For the intervention x load interaction, post-hoc analysis revealed significantly faster berry performance, in comparison to placebo, for medium (\(p\) = 0.026) and low (\(p\) = 0.022) load trials. Additional post-hoc analysis further qualified this finding by revealing significantly faster berry response times in comparison to placebo on low load trials at 2 h (\(p\) = 0.031) and 4 h (\(\mathrm{ms}\); \(p\) = 0.030),  
Figure 4: Reaction time (\(\pm\) SE of the mean) as a function of intervention and session, showing significantly faster berry performance at 2 and 4 h in comparison to the placebo and a significantly faster berry performance between 2 and 4 h. Note there was a trend towards significance at 6 h for faster berry performance in comparison to the placebo and a trend for faster placebo performance between 2 and 4 h. Baseline performance, included as a covariate in the analysis, is shown separated by the dotted line. \(+\)\(p\) < 0.1, \({}^{*}\)\(p\) < 0.05, \(\#\)\(p\) < 0.01.  
and also medium load trials at 4 h (\(p\) = 0.002). Furthermore, there were significantly faster response times at 4 h in comparison to 2 h on medium load trials for the Berry intervention (\(p\) = 0.031) whilst there was no such benefit for the placebo. The results here demonstrate better response time performance for the berry intervention in general with benefits particularly evident at the 2 and 4 h sessions. The predicted cognitive demand/fatigue effects were not found for these response time measures with the benefits being shown on a spread of congruent, incongruent, low load, and medium load trials. This indicates that the response times effects found here are more global in nature in contrast to the accuracy benefits which were found on the more cognitively demanding trials as outlined above.