No New Neurons for Smell?

Excerpt: The finding may mean that as humans evolved from animals, we lost the ability to produce new neurons in this area because we don’t rely as much on our sense of smell. On the other hand, it may mean that people living in an affluent, Western city like Stockholm aren’t exposed to enough new smells to keep the neurons alive.

My comment:

Evidence for the epigenetic effects of nutrient chemicals and pheromones on mammalian olfactory bulb neurogenesis, hypothalamic neurogenesis and hippocampal neurogenesis attest to design in biology. For example, nutrient chemicals are required for survival of individual organisms in the ecological niche where pheromones control interactions in the social niche of microbes.

In the honeybee model organism, this obvious design, where nutrients and pheromones are both required, extends to brain development. What the queen bee eats determines her pheromone production and everything about the interactions of every other organism in the colony — including the neuroanatomy of the worker bees’ brains.

An extension of this model to vertebrates is found in nutrient-dependent ecological niches of the threespine stickleback that determine their social niches and speciation. Extending this model of transgenerational epigenetic inheritance from yeasts to mammals is done by examining the direct effect of nutrient chemicals, like glucose, and the direct effect of pheromones on the gonadotropin releasing hormone neurons of the hypothalamic neurogenenic niche that is responsible for luteinizing hormone secretion, fertility, steroidogenesis, sex differences in behavior, brain development (among other things), and learning and memory via hippocampal neurogenesis.

Any study that indicates no olfactory bulb neurogenesis occurs in adult humans argues against the design in biology that ensures the plasticity of our brain-directed behavioral response to novel stimuli in our environment, like the visual and auditory input associated with the development of behavior via correlates with the direct effect of nutrient chemicals and pheromones.

Is there another model for the epigenetic effects of sensory input (like food odors and social odors/pheromones) that directly effect the hormones that affect our behavior via basic principles of biology and neuroscientifically established levels of biological organization? If not, the ‘right’ model of nutrient chemical and pheromone activation of genes in hormone secreting nerve cells of brain tissue (i.e., in the organ of the organ system responsible for our behavior) suggests that the results of this study are misleading.  Positing a lesser role for olfaction or for olfactory bulb neurogenesis  in humans is inconsistent with the fact that olfaction and odor receptors provide a clear evolutionary trail that can be followed from unicellular organisms to insects to humans.

About James V. Kohl 1307 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