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The acute tryptophan depletion (ATD) technique has been used extensively to study the effect of low serotonin in the human brain. This review assesses the validity of a number of published criticisms of the technique and a number of previously unpublished potential criticisms. The conclusion is that ATD can provide useful information when results are assessed in conjunction with results obtained using other techniques. The best-established conclusion is that low serotonin function after tryptophan depletion lowers mood in some people. However, this does not mean that other variables, altered after tryptophan depletion, are necessarily related to low serotonin. Each aspect of brain function has to be assessed separately. Furthermore, a negative tryptophan depletion study does not mean that low serotonin cannot influence the variable studied. This review suggests gaps in knowledge that need to be filled and guidelines for carrying out ATD studies. [ABSTRACT FROM AUTHOR]

Recent clinical trials suggest that 3 single biological treatments have effects that persist. Based on research showing that the muscles involved in facial expressions can feed back to influence mood, a single trial diminishing glabella frown lines with botulinum toxin demonstrated a significant antidepressant effect for 16 weeks. Based primarily on research with animal models of depression suggesting that glutamate may be involved in depression, the N-methyl-D-aspartate antagonist ketamine has been tested in several trials. A single dose decreased depression for up to a week. The reported effects of the use of mushrooms containing psilocybin by a number of cultures around the world has stimulated several trials showing beneficial effects of a single dose of psilocybin for over a year in healthy people, and for up to 3 months in patients with anxiety disorders who have advanced cancer. This article discusses these studies, their rationale, their possible mechanisms of action, the future clinical research required to establish these therapies and the basic research required to optimize single treatments that have lasting effects. [ABSTRACT FROM AUTHOR]

In this article the author, in his last editorial, reflects on the 21 years on the editorial board and 11 years as coeditor-in-chief of the Journal of Psychiatry and Neuroscience (JPN). He discusses the strengths of the journal and describes some of his professional experiences and insights about the publication process. Also noted is his editorial sojourn with JPN and his interactions with the editorial board, the authors, and the role of manuscript reviewers.

Focuses on the promises and limitations of genetic research for medical and psychiatric disorders. Link between specific gene and a disorder; Link between Lesch-Nyhan syndrome severity and deficiency of hypoxanthine phosphoribosyltransferase; Role of serotonin in brain development.

Summarizes lectures and symposia at the 22nd annual meeting of the Canadian College of Neuropsychopharmacology from June 12 to 15, 1999 in Halifax, Nova Scotia. Includes lectures on possible schizophrenia researches; Symposium on pain, mood, and anxiety disorders; Winners of the CCNP Young Investigator and Heinz Lehmann Award lectures.

Editorial. Focuses on the understanding of brain disorders. Importance of lipids as constituent of the brain; Role of impaired fatty acid and phospholipid metabolism in the etiology of psychiatric disorders; Relevance to the development of biological psychiatry; Association between the consumption of omega-3 fatty acids and prevalence of depression.

The article offers information on bright light treatment for nonseasonal and seasonal depression, and highlights the case of a 58-year-old man being treated with selective serotonin reuptake inhibitor (SSRI), who sought a more natural treatment for episodes of depression. It mentions a Cochrane review which suggests that bright light, at 2500 lux or more can help improve moods and sleep efficiency, and reduce depression.

Editorial. Comments on the preliminary sequencing of the human genome. Importance of knowledge on the process; Information needed to produce human being; Discovery of genes through sequencing of the human genome.

A letter to the editor is presented in response to the article "Single Treatments That Have Lasting Effects: Some Thoughts on the Antidepressant Effects of Ketamine and Botulinum Toxin and the Anxiolytic Effect of Psilocybin" by Simon N. Young in the 2013 issue, including a response from the author of the article.

The article focuses on L-Tyrosine regarding alleviation of the effects of stress. The reported effects of L-tyrosine are acute effects in preventing a decline in cognitive function in response to physical stressors such as lower body negative pressure stress, cold stress and others. Moreover, he mentions that the use of L-tyrosine cannot be recommended for patients and those who are taking it need to be educated regarding its long-term safety.

Discusses the use of tryptophan as a natural dietary hypnotic. Physiological effects of tryptophan; Side-effects; Drug dosage.