Using the NIMH Research Domain Criteria (RDoC) in human and nonhuman primate research

“Natural Laboratory Complex” for novel primate neuroscience

We propose novel strategies for primate experimentation that are ethically valuable and pragmatically useful for cognitive neuroscience and neuropsychiatric research. Specifically, we propose Natural Laboratory Complex or Natural Labs, which are a combination of indoor-outdoor structures for studying free moving and socially housed primates in natural or naturalistic environment. We contend that Natural Labs are pivotal to improve primate welfare, and at the same time to implement longitudinal and socio-ecological studies of primate brain and behavior. Currently emerging advanced technologies and social systems (including recent COVID-19 induced “remote” infrastructures) can speed-up cognitive neuroscience approaches in freely behaving animals. Experimental approaches in natural(istic) settings are not in competition with conventional approaches of laboratory investigations, and could establish several benefits at the ethical, experimental, and economic levels.

A novel mind-set in primate experimentation: Implications for primate welfare

We emphasize the importance of studying the primate brain in cognitive neuroscience and suggest a new mind-set in primate experimentation within the boundaries of animal welfare regulations. Specifically, we list the advantages of investigating both genes and neural mechanisms and processes in the emergence of behavioral and cognitive functions, and propose the establishment of an open field of primate research. The latter may be conducted by implementing and harmonizing experimental practices with ethical guidelines that regulate (1) management of natural parks with free-moving populations of target nonhuman primates, (2) establishment of indoor-outdoor labs for both system genetics and neuroscience investigations, and (3) hotel space and technologies which remotely collect and dislocate information regarding primates geographically located elsewhere.

Integrating DSM/ICD, Research Domain Criteria, and Descriptive Psychopathology in Teaching and Practice of Psychiatry

Background: Some believe that Psychiatry relies solely on the Diagnostic and Statistical Manual of Mental Disorders (DSM). Some are not aware of the effort initiated by the Research Domain Criteria (RDoC) to propel the field to a new era of Medicine. Others are not acquainted with studies of Descriptive Psychopathology that can dissect symptoms and signs of mental illness and convert them into reliable clinical data for diagnosis and treatment purpose. This document is to bring keenness of the advances in research, translational or clinical, made in Psychiatry, and to encourage students, psychiatric residents, as well as psychiatric practitioners to integrate DSM/ICD, RDoC, and Descriptive Psychopathology into teaching and practice. Methods: A search of the literature originated from 1985 to 2018 on two central databases: Google Scholar and Pubmed by free-texting: "comparison, strengths and weaknesses, Diagnostic and Statistical Manual of Mental Disorders, Research Domain Criteria, and Descriptive Psychopathology." Results: The DSM and ICD possess algorithms for psychiatric diagnosis, but they are limited to determine psychobiological causes of mental illnesses. Descriptive Psychopathology aims to dissect the mind to understand better "signs and symptoms," their psychological, neurological, or neuropsychological origins but has been criticized for being non-reliable to practically explain the meaning of signs and symptoms that it attempts to describe. The RDoC claims to be a data-driven system of biological and psychological research for an evidence-based approach to Psychiatry. It is said that RDoC utilizes translational research that has been very slow to move to human experimentation. Discussion and conclusion: Despite incommensurable translational research and human trials, the integration of translational research (neurosciences, experimental psychology, and genomics) as available human research data into teaching and practice is lacking. The author believes that the integration will enhance scientific and well-founded communication with our peers, advance psychopharmacologic treatments and improve our patient's mental well-being.

Regulation of emotional response in juvenile monkeys treated with fluoxetine: MAOA interactions

Juvenile male rhesus macaques received therapeutic doses of fluoxetine daily from one to three years of age and were compared to vehicle-treated controls (N=16/group). Genotyping for monoamine oxidase A (MAOA) polymorphisms was used to form subgroups (N=8) with high and low expression of the gene. Behavioral responses were scored during 30-second exposures to pictures differing in affective content. As expected from its therapeutic effect, fluoxetine decreased the behavioral response to emotionally evocative pictures. A 44% reduction in number of expressive behaviors was seen, but only in subjects with low expression MAOA polymorphisms. In general, this effect occurred for pictures of varying affective content and was not due to altered occurrence of one specific behavior or type of behavior. The drug*genotype interaction was seen after one and two years of treatment and did not reverse one year after discontinuation of dosing. Two potential translational implications are suggested: (1) MAOA genetic polymorphisms may be the source of some of the variability in response to fluoxetine treatment in children; (2) extended fluoxetine treatment during juvenile brain development may result in persistent effects on emotional regulation.