Mitochondria interface genetic/epigenetic responses to psychological stress

This 2015 Pennsylvania rodent study found: “Mitochondria can regulate complex whole-body physiological responses, impacting stress perception at the cellular and organismal levels. Mitochondrial dysfunctions altered the hypothalamic–pituitary–adrenal axis, sympathetic adrenal–medullary activation and catecholamine levels, the inflammatory cytokine IL-6, circulating metabolites, and hippocampal gene expression responses to stress. Stress-induced neuroendocrine, inflammatory, metabolic, and transcriptional responses coalesced … Continue reading Mitochondria interface genetic/epigenetic responses to psychological stress

An interview with Dr. Rachel Yehuda on biological and conscious responses to stress

How Trauma and Resilience Cross Generations “The purpose of epigenetic changes, I think, is simply to increase the repertoire of possible responses. So let’s say, for some reason, your parents transmitted to you biologic changes that are very appropriate to starvation, but you don’t live in a culture where food is not plentiful. You’re just … Continue reading An interview with Dr. Rachel Yehuda on biological and conscious responses to stress

A possible link between stress responses and human cancers?

This 2015 UK rodent study found: “An unexpected role for the GR [glucocorticoid receptor] in promoting accurate chromosome segregation during mitosis. We also identify reduced GR expression in several common human cancers, thereby implicating GR as a novel tumor suppressor gene.” One of the researchers said: “Cancer is caused by cell division going wrong, but … Continue reading A possible link between stress responses and human cancers?

Can you give emotionally informed yet reasoned responses to moral questions within 3 seconds?

Could you give a 3-second informed decision that reflected your true feelings about this statement? “Inflicting emotional harm is just as bad as inflicting physical harm.” Could you then express your confidence about your answer on a 1-7 scale within 1 second? How about your 3-second response to this statement? “Developing a child’s character is … Continue reading Can you give emotionally informed yet reasoned responses to moral questions within 3 seconds?

Fear extinction is the learned inhibition of retrieval of previously acquired responses

This 2014 rodent study showed that fear extinction doesn’t depend on memory retrieval: “These results show that extinction and retrieval are separate processes and strongly suggest that extinction is triggered or gated by the conditioned stimulus even in the absence of retrieval.” The key to my understanding this finding came from a definition in another … Continue reading Fear extinction is the learned inhibition of retrieval of previously acquired responses

Task performance and beliefs about task responses are solely cerebral exercises

This 2013 human study provided details of which areas of the cerebrum participated in objective performance of a task vs. the subjects’ subjective confidence in their task responses: “These results suggest the existence of functional brain networks indexing objective performance and accuracy of subjective beliefs distinctively expressed in a set of stable mental states.” The … Continue reading Task performance and beliefs about task responses are solely cerebral exercises

Face-selective neurons maintain consistent visual responses across months

This 2014 primate study provided additional details on the specialized brain circuits for recognizing faces: “The current finding that neurons commonly give similar responses upon seeing the same faces months apart raises the possibility that some neurons might respond the same way to the same individual faces over most of the animal’s lifespan.” But the … Continue reading Face-selective neurons maintain consistent visual responses across months

Prenatal stress produces offspring who as adults have cognitive, emotional, and memory deficiencies

This 2018 French/Italian/Swiss rodent study used the prenatally restraint stressed (PRS) model to create problems that could be resolved by various chemicals: “S 47445 is a positive modulator of glutamate AMPA-type receptors, possessing neurotrophic and enhancing synaptic plasticity effects as well as pro-cognitive and anti-stress properties. Most of studies examining the antidepressant effects of new … Continue reading Prenatal stress produces offspring who as adults have cognitive, emotional, and memory deficiencies

Manufacturing PTSD evidence with machine learning

What would you do if you were a scientist who had strong beliefs that weren’t borne out by experimental evidence? Would you be honest with yourself about the roots of the beliefs? Would you attempt to discover why the beliefs were necessary for you, and what feelings were associated with the beliefs? Instead of the … Continue reading Manufacturing PTSD evidence with machine learning

The role of DNMT3a in fear memories

This 2018 Chinese rodent study found: “Elevated Dnmt3a [a DNA methyltransferase] level in the dorsal dentate gyrus (dDG) of hippocampus was associated with the absence of fear renewal in an altered context after extinction training. Overexpression and knockdown of Dnmt3a in the dDG regulated the occurrence of fear renewal in a bi-directional manner. We found … Continue reading The role of DNMT3a in fear memories