Social decision-making in vertebrates (Part 2)
June 1, 2012 | James Kohl
Science 1 June 2012:
Evolution of a Vertebrate Social Decision-Making Network
Across vertebrates, behaviorally relevant brain regions are remarkably conserved over 450 million years of evolution.
An additional comment:
Re: The Intersection of Neurotoxicology and Endocrine Disruption. NeuroToxicology, by Bernard Weiss
…hormones help steer the process of brain development.
…sex differences in behavior are primarily the outcomes of differences in how the brain is sexually differentiated during early development by gonadal hormones (the Organizational Hypothesis).
… environmental chemicals are capable of altering these underlying events and processes. Among those chemicals, the group labeled as endocrine disrupting chemicals (EDCs) offers the clearest evidence of such selectivity…
In Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors, I concluded that the clearest evidence for chemicals that alter the underlying events and processes of brain development and its sexual differentiation is found in the epigenetic effects of nutrient chemicals and pheromones, which are responsible for the adaptive evolution of species from microbes to man.
Focus on endocrine disruption establishes what happens when toxic chemicals alter the same events and processes of brain development and its sexual differentiation via epigenetic effects on gonadotropin releasing hormone (GnRH) pulsatility, luteinizing hormone, olfactory bulb neurogenesis, hippocampal neurogenesis, learning, and memory in vertebrates.
For contrast, I’ve modeled the epigenetic effects of food odors and pheromones on homeostasis and species diversification, and for many years, my friend Teresa Binstock stressed the importance of endocrine disruption (specifically due to bisphenol A and phthalates) on J. Michael Bailey’s “Sexnet”. Now that the basic principles of biology and levels of biological organization, which link sensory input from the environment directly to behavior via intracellular signaling and stochastic gene expression, have been clarified by work with model organisms, I look forward to learning if there are any reasons to avoid the incorporation of current information on endocrine disruption into existing studies of the development of human sexual behavior.
Comparing typical and atypical epigenetic effects that appear to extend to transgenerational epigenetic inheritance seems even more important now than in 1996, when with Milton Diamond, Teresa Binstock and I co-authored: From fertilization to adult sexual behavior, which appeared in the journal Hormones and Behavior.