Nootropic Modulation of Neural Plasticity and Memory

Abstract

Nootropics are a class of compounds characterised by putative cognitive enhancers and neuroprotective agents. In the research explicated in this thesis, I investigate nootropic modulation of neural plasticity, brain activity related to memory, and memory performance. I study a well-known and ubiquitous nootropic drug, caffeine, and contrast it with a nootropic dietary supplement blend called Ārepa, code-named the juice in this research. Caffeine is a fascinating nootropic drug, relied upon by much of humanity for arousing cognitive enhancement. It is an adenosine receptor antagonist that improves several forms of cognitive performance. Research in laboratory animals discovered caffeine can modulate synaptic plasticity and long-term potentiation (LTP), but this has not been corroborated in humans. Neural oscillations related to memory under caffeine have also not been probed. The juice is an interesting novel nootropic drink containing L-theanine, pine bark extract, and blackcurrant extract and juice. Its effects on neural plasticity, oscillations, and memory performance are untested. In this thesis, I delineate the design, conduction, and findings of two double-blind placebo-controlled crossover clinical trials in which I use electroencephalography (EEG) to examine the effects of caffeine and the juice upon brain activity, neural plasticity, and memory. Moreover, I describe issues and artifacts typical of EEG recordings, review methods that can be used to clean EEG data, and derive two novel corrections. I discover that caffeine positively potentiates neural plasticity in humans, which may be a positive effect on human LTP or the induction of LTP. I do not find that the juice affects neural plasticity. I contribute to existing evidence of the effects of caffeine on memory performance. I find that the juice does not affect memory performance. I discover that caffeine modulates neural oscillations during working memory retention and recall. I find that the juice modulates neural oscillations related to working memory recall and speculate that it may do so during memory retention. I replicate and contribute to existing evidence of the effects of caffeine on resting state brain activity. I demonstrate that the methodology elucidated in this thesis is able to detect nootropic modulation of neural plasticity, brain activity related to memory, and memory performance.