How technical progress reshaped behavioral neuroendocrinology during the last 50 years and some methodological remarks.

The first issue of Hormones and Behavior was published 50 years ago in 1969, a time when most of the techniques we currently use in Behavioral Endocrinology were not available. Researchers have during the last 5 decades developed techniques that allow measuring hormones in small volumes of biological samples, identify the sites where steroids act in the brain to activate sexual behavior, characterize and quantify gene expression correlated with behavior expression, modify this expression in a specific manner, and manipulate the activity of selected neuronal populations by chemogenetic and optogenetic techniques. This technical progress has considerably transformed the field and has been very beneficial for our understanding of the endocrine controls of behavior in general, but it did also come with some caveats. The facilitation of scientific investigations came with some relaxation of methodological exigency. Some critical controls are no longer performed on a regular basis and complex techniques supplied as ready to use kits are implemented without precise knowledge of their limitations. We present here a selective review of the most important of these new techniques, their potential problems and how they changed our view of the hormonal control of behavior. Fortunately, the scientific endeavor is a self-correcting process. The problems have been identified and corrections have been proposed. The next decades will obviously be filled with exciting discoveries in behavioral neuroendocrinology.

[Optogenetics: its history, fundamentals and relevance in the present and the past]. / Optogenética: historia, fundamentos y relevanciapresente y future.

INTRODUCTION: Optogenetic is an experimental technique that combines genetic engineering and optical physics procedures to mark specific neurons in the brain and activate them at will through rays of light of certain frequency. AIM: To explain, to readers not versed in genetics the history, the rationale and the present and future applications of optogenetic in brain and mental processes research. DEVELOPMENT: The current development of this technique is allowing considerable advances in accurate knowledge about the neural circuits that control behavior and motivational and cognitive states, like hunger and thirst, pain, sleep or learning and memory. Among the first shocking results there are the creation and control of false memories. CONCLUSIONS: The optogenetics is a revolutionary experimental technique called to replace some of the classics techniques in brain behavior research and an important way in the development and control of mental processes and in the treatment of their diseases.

TITLE: Optogenetica: historia, fundamentos y relevancia presente y futura.Introduccion. La optogenetica es una tecnica experimental que combina procedimientos de ingenieria genetica y de fisica optica para marcar neuronas especificas del cerebro y poder activarlas despues a voluntad mediante rayos de luz de determinada frecuencia. Objetivo. Explicar a los lectores, especialmente a los no versados en genetica, la historia, los fundamentos y las aplicaciones presentes y futuras de la optogenetica en la investigacion sobre el cerebro y los procesos mentales. Desarrollo. El desarrollo actual de esta tecnica esta permitiendo considerables avances en el conocimiento preciso sobre los circuitos neuronales que controlan conductas y estados motivacionales y cognitivos especificos, como el hambre y la sed, el dolor, el sueño, o el aprendizaje y la memoria. Entre los primeros resultados impactantes destacan los que han hecho posible la creacion y el control cerebral de falsas memorias. Conclusiones. La optogenetica es una tecnica revolucionaria llamada a sustituir algunas de las tecnicas clasicas en la investigacion cerebral y a abrir un importante y nuevo camino en el desarrollo y control de los procesos mentales y en la terapia de sus patologias.

The Brain Prize 2013: the optogenetics revolution.

The 2013 Grete Lundbeck European Brain Research Prize was awarded to Ernst Bamberg, Edward Boyden, Karl Deisseroth, Peter Hegemann, Gero Miesenböck, and Georg Nagel 'for their invention and refinement of optogenetics'. Why optogenetics? And why this sextet? To appreciate why, we turn first to some of the core questions of neuroscience and the technical difficulties that long obstructed their resolution.