Advances in Natural Medicines, Nutraceuticals and Neurocognition by Con Stough and Andrew Scholey, eds. Boca Raton, FL: CRC Press; 2013. Hardcover, 369 pages. ISBN: 978-1-4398-9360-9. $149.95.
The editors of this book have been doing research in this field throughout their careers and have co-authored two of the 16 chapters. Andrew Scholey, PhD, is a professor of behavioral and brain sciences and Con Stough, PhD, is a professor of cognitive neuroscience. Together they direct the Centre for Human Psychopharmacology at Swinburne University in Melbourne, Australia.
This book is divided into four parts: (1) Methodologies to Measure Cognition in Natural Medicine Trials; (2) Vitamins and Nutrients; (3) Essential Fatty Acids and Neurocognition; and (4) Herbal Medicines, Nutraceuticals and Neurocognition.
“Methodologies to Measure Cognition” (Part 1; two chapters) is not without controversy; this is apparent when reading the section. The parameters of memory that are measured most often are ideally those associated with mild cognitive impairment, which may be a prodrome to states of dementia (from which there is currently no return) such as Alzheimer’s disease. Most studies, however, use normal or normal elderly adults. Significant effects are hard to come by, perhaps because enhancing memory above “normal” is difficult and may not be relevant to delaying memory loss in elderly patients. Delaying memory loss is really the goal of therapeutic intervention, and so far no treatments (including pharmaceuticals) have been shown to be effective.
Part 2 has five chapters that examine various isolated compounds, including B vitamins and antioxidant vitamins, N-acetylcysteine, zinc, and lipoic acid. The rationale for using these agents is based mostly on the notion that senility and dementia are caused by increased oxidative stress during aging. These nutrients are thought to intervene somewhere in the cascade of events involving oxidation and inflammation, which first leads to neuronal dysfunction (which may be reversible) and ultimately to neuronal degeneration (which is probably not reversible). While there is some evidence in animal models that it may be possible to enhance the formation of new neuronal cells, this is controversial, and it is unclear if the cells are really functional. Most of the information presented in these chapters is used to explain the theoretical basis for why these agents might interact with pathological processes. Clinical evidence is rare, and evidence based on epidemiology studies can demonstrate only correlation, not causality. Data based on food frequency questionnaires are not really useful and often lead to incorrect conclusions. Failure to find evidence in favor of something is not equivalent to finding evidence against it. This is especially true for epidemiology studies. Meta-analyses that include poor-quality studies using ineffective doses don’t improve the science. I also was disappointed at the lack of discussion regarding the relative physiologic and neuroprotective roles of different vitamin isomers and of optimal doses in various populations and how this can affect results. An annoyance of this and other sections is that much of the information is rather old. There are almost no references published after 2009.
Part 3 consists of two chapters that describe the roles of essential fatty acids (EFAs) in neurocognition. These chapters were particularly well written and noticeably more positive in relation to the potential for prevention and treatment of cognitive decline. Unlike the antioxidants or even the anti-inflammatories, which largely rely on this single mechanism, EFAs (especially the long-chain omega-3s) affect multiple systems and pathways that are known to be involved with pathological neurodegenerative processes. In addition, they are one of the major structural components of brain phospholipid membranes. While deriving conclusions from the literature can be problematic since faulty data derived from food questionnaires and treatment studies with ineffective doses have been included, there remains a core of compelling evidence suggesting that omega-3 is central to cognition. The large literature on the positive role of omega-3 in mood disorders and other psychiatric conditions is consistent with positive effects on cognition. Supporting evidence includes the critical role in neurodevelopment and of neuroprotection in animals and humans.
Part 4 comprises seven chapters dealing with the possible effects of herbal medicines and various nutraceuticals on neurocognition. Chinese medicine, a green tea (Camellia sinensis, Theaceae) extract (epigallocatechin), huperzine (from Huperzia serrata, Lycopodiaceae), and wine-derived phenolics each have their own chapter. Two chapters are devoted to Bacopa monnieri (Plantaginaceae); the first by the editors on human clinical effects is rather encouraging. In addition to a long history of traditional use in Ayurveda, there is considerable modern evidence supporting beneficial effects of bacopa. (The government of Australia is supporting a large intervention study that will look at mechanisms.) The second bacopa chapter is mostly on animal studies performed at the Central Drug Research Institute in Lucknow, India. While H. serrata is a Chinese medicine, huperzine has its own chapter due to the relatively large amount of modern data. Huperzine is of interest in Western medicine perhaps because its pharmacology is similar in some ways to drugs approved for the treatment of Alzheimer’s (cholinesterase inhibitors).
In summary, the chapters of this book have been assembled by the editors around the topic of natural treatments for neurocognition, though each chapter really stands alone. Some chapters are better than others but all contain rather old references, suggesting that the book started its life some years ago but only recently was published. I agreed to review this book because I wanted my own copy to serve as a future reference. As a psychopharmacologist, I read and enjoyed every page, and I think others will too.
—Jerry Cott, PhD Pharmacologist Silver Spring, Maryland