How memory works

A Conversation With Eric R. Kandel

A Quest to Understand How Memory Works

Excerpt: “…long-term memory alters the expression of genes in nerve cells, which is the cause of the growth of new synaptic connections. When you see that at the cellular level, you realize that the brain can change because of experience. It gives you a different feeling about how nature and nurture interact. They are not separate processes.”

My comment:
Sensory input links nurture (the social environment) to nature (genetic predisposition). In mammals it does this via direct effects of sensory input on genes in hormone-secreting nerve cells of the brain. Food odors and social odors called pheromones directly effect genes in nerve cells of brain tissue that secretes gonadotropin releasing hormone (GnRH). Understanding the evolution of the pathways that effect changes in the mammalian GnRH neuronal system and GnRH secretion is the key to understanding the basic principles of biology and levels of biological organization required to link nature to nurture in species from microbes to man.

Nowhere is this more clearly stated than in Feedback loops link odor and pheromone signaling with reproduction. Boehm U, Zou Z, Buck LB. Cell. 2005 Nov 18;123(4):683-95. What is it that is not understood about the influence of human pheromones on sexual behavior? They wrote on page 683: “Indications that GnRH peptide plays an important role in the control of sexual behaviors suggest that pheromone effects on these behaviors might also involve GnRH neurons.” Obviously, I think that in this context control is the operative word. Who argues for the primary role of visual input in the control of human sexual behavior, and what is the biological basis for that argument? Is there an animal model for that?

How does any other animal model for the control of sexual behavior compare to existing animal models that have established the role of pheromones in hippocampal neurogenesis? See: Reproduction: a new venue for studying function of adult neurogenesis? Lau BW, Yau SY, So KF. Cell Transplant. 2011;20(1):21-35.  For example, these authors write:  “pheromone exposure increases hippocampal neurogenesis” and “it was confirmed that the hippocampal neurogenesis is due to the increase of the luteinizing hormone”

It is the GnRH neuronal system that modulates the secretion of LH, which links sex and the sense of smell. Only via the effect of pheromones on GnRH and LH can the incentive salience of visual input be correlated with biologically based cause and effect. And correlation (e.g., as with vision) is not cause. Visual input does not directly effect genes in GnRH neurosecretory cells of brain tissue, and it can only affect behavior via association with the olfactory/pheromonal input that does.



About James V. Kohl 1308 Articles
James Vaughn Kohl was the first to accurately conceptualize human pheromones, and began presenting his findings to the scientific community in 1992. He continues to present to, and publish for, diverse scientific and lay audiences, while constantly monitoring the scientific presses for new information that is relevant to the development of his initial and ongoing conceptualization of human pheromones. Recently, Kohl integrated scientific evidence that pinpoints the evolved neurophysiological mechanism that links olfactory/pheromonal input to genes in hormone-secreting cells of tissue in a specific area of the brain that is primarily involved in the sensory integration of olfactory and visual input, and in the development of human sexual preferences. His award-winning 2007 article/book chapter on multisensory integration: The Mind’s Eyes: Human pheromones, neuroscience, and male sexual preferences followed an award winning 2001 publication: Human pheromones: integrating neuroendocrinology and ethology, which was coauthored by disinguished researchers from Vienna. Rarely do researchers win awards in multiple disciplines, but Kohl’s 2001 award was for neuroscience, and his 2007 “Reiss Theory” award was for social science. Kohl has worked as a medical laboratory scientist since 1974, and he has devoted more than twenty-five years to researching the relationship between the sense of smell and the development of human sexual preferences. Unlike many researchers who work with non-human subjects, medical laboratory scientists use the latest technology from many scientific disciplines to perform a variety of specialized diagnostic medical testing on people. James V. Kohl is certified with: * American Society for Clinical Pathology * American Medical Technologists James V. Kohl is a member of: * Society for Neuroscience * Society for Behavioral Neuroendocrinology * Association for Chemoreception Sciences * Society for the Scientific Study of Sexuality * International Society for Human Ethology * American Society for Clinical Laboratory Science * Mensa, the international high IQ society