Lemon balm (Melissa officinalis) has been used historically and contemporarily as a modulator of mood and cognitive function, with anxiolytic effects following administration of capsules, coated tablets and topical application. Following a pilot study with lemon balm extract administered as a water based drink, which confirmed absorption of rosmarinic acid effects on mood and cognitive function, we conducted two similar double-blind, placebo-controlled, crossover studies. These evaluated the mood and cognitive effects of a standardised M. officinalis preparation administered in palatable forms in a beverage and in yoghurt. In each study a cohort of healthy young adults’ self-rated aspects of mood were measured before and after a multi-tasking framework (MTF) administered one hour and three hours following one of four treatments. Both active lemon balm treatments were generally associated with improvements in mood and/or cognitive performance, though there were some behavioral “costs” at other doses and these effects depended to some degree on the delivery matrix.

Previous work has identified the positive effects of the acute administration of a multivitamin-guaraná preparation during an effortful executive/working memory task. Here, we aimed to differentiate the effects of multivitamins with and without guaraná and to examine the neural substrates of such effects using functional magnetic resonance imaging (fMRI). Following a double-blind, placebo-controlled, randomised, balanced crossover design, 20 participants (mean age 29 ± 5.54 years) consumed multivitamin preparations with or without guaraná (Berocca^® Performance and Boost, respectively) and a placebo. Thirty minutes post-treatment, they underwent neurocognitive assessment, consisting of a 10 min Cognitive Demand Battery, with mood ratings taken immediately before and after the battery. Five additional participants underwent post-treatment fMRI scanning during Rapid Visual Information Processing and Inspection Time activation tasks. The multivitamin with guaraná treatment was associated with significantly enhanced Serial Threes performance and self-rated contentment. fMRI revealed that both multivitamin treatments increased activation in areas associated with working memory and attentional processing, with the effect being greater in the multivitamin with guaraná condition. These data confirm the acute benefits of multivitamins with guaraná on mood and cognitive performance. Furthermore, they demonstrate for the first time increased brain activation from multivitamin preparations both with and without guaraná, as measured using fMRI.

The Rapid Visual Information Processing (RVIP) task, a serial discrimination task where task performance believed to reflect sustained attention capabilities, is widely used in behavioural research and increasingly in neuroimaging studies. To date, functional neuroimaging research into the RVIP has been undertaken using block analyses, reflecting the sustained processing involved in the task, but not necessarily the transient processes associated with individual trial performance. Furthermore, this research has been limited to young cohorts. This study assessed the behavioural and functional magnetic resonance imaging (fMRI) outcomes of the RVIP task using both block and event-related analyses in a healthy middle aged cohort (mean age = 53.56 years, n = 16). The results show that the version of the RVIP used here is sensitive to changes in attentional demand processes with participants achieving a 43% accuracy hit rate in the experimental task compared with 96% accuracy in the control task. As shown by previous research, the block analysis revealed an increase in activation in a network of frontal, parietal, occipital and cerebellar regions. The event related analysis showed a similar network of activation, seemingly omitting regions involved in the processing of the task (as shown in the block analysis), such as occipital areas and the thalamus, providing an indication of a network of regions involved in correct trial performance. Frontal (superior and inferior frontal gryi), parietal (precuenus, inferior parietal lobe) and cerebellar regions were shown to be active in both the block and event-related analyses, suggesting their importance in sustained attention/vigilance. These networks and the differences between them are discussed in detail, as well as implications for future research in middle aged cohorts.