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In the current study, sixty healthy older adults aged 50 years or older, and who were light to moderate coffee drinkers, were administered 6g of a decaffeinated green coffee blend (NESCAFÉ Green Blend coffee; GB) or 540mg pure chlorogenic acids (CGA) or placebo in a double-blind acute cross-over design, with cognitive and mood assessments pre-dose, 40-mins and 120-mins post-dose. The primary outcome measure was accuracy in Rapid Visual Information Processing (RVIP). Secondary cognitive outcome measures included RVIP reaction time as well as Inspection time (IT), Jensen Box decision/reaction times, serial subtraction and N-Back working memory. Secondary mood measures included Bond-Lader and caffeine Research visual analogue scales (VAS). No significant treatment effects were found for the primary outcome measure, although significant effects were found amongst secondary measures. Overall, CGA in isolation was not found to significantly improve cognitive function relative to placebo whereas the GB was found to improve sustained attention as measured by the N-Back task in comparison to placebo overall (t=2.45,p=.05), as well as decision time on a 2-choice reaction time task (Jensen box) in comparison to placebo at 40 minutes post-dose (t=2.45,p=.05). Similarly, GB was found to improve alertness on both the Bond-Lader at 120 minutes relative to CGA (t=2.86, p=0.02) and the caffeine Research VAS relative to CGA (t=3.09, p=0.009) and placebo (t=2.75,p=0.02) at 120 minutes post-dose. Both the GB and CGA were also found to significantly improve symptoms of headache at 120 minutes relative to placebo (t=2.51,p=0.03 and t=2.43,p=.04 respectively), whilst there was a trend towards a reduction in jitteriness with GB and CGA in comparison to placebo at 40 minutes post-dose (t=2.24,p=0.06 and t=2.20,p=0.06 respectively). These findings suggest that the improvements in mood observed with GB, but not the improvements in cognitive function, are likely to some extent to be attributab

Objectives: Methamphetamine is considered to be one of the most popularly abused drugs by drivers; however, its exact effect on driving and driving behaviour has yet to be thoroughly investigated. This being despite methamphetamine's increased prevalence in injured and deceased drivers. Methods: Twenty healthy recreational illicit stimulant users (10 male and 10 female), aged between 21 and 32 years (mean = 25.4 years, SD = 3.3 years) attended two testing sessions involving oral consumption of 0.42 mg/kg d-methamphetamine or a matching placebo. The drug administration was counter-balanced, double-blind, and medically supervised. At each session driving, performance was assessed 2.5 h post drug administration. Results: d-methamphetamine (0.42 mg/kg) did not significantly impair overall simulated driving performance 2.5 h post drug administration. At the individual driving variable level, participants in the d-methamphetamine condition were observed to be driving slower when an emergency situation occurred (T = 44, p < 0.05), but interestingly, participants in both conditions recorded average speeds in excess of the speed limit (100 km/h) when the emergency situations occurred. The d-methamphetamine condition did also produce four times more infringements where participants did not stop at red traffic light in comparison to the placebo, but this effect was only evident at a trend level (T = 7, p = 0.11). Conclusions: The findings presented herein suggest that d-methamphetamine administered at the levels supplied did not impair driving performance in a manner consistent with epidemiological evidence. Further research is certainly required to elucidate the effects of various doses of methamphetamine, alone and in combination with other legal and illicit substances.