New research from Emory University School of Medicine in Atlanta suggests that memories can hitch a ride on DNA and be passed on to future generations. Scientists (and Spiritualists) have long theorized that memories acquired during a lifetime are passed on to subsequent generations…but it turns out these memories aren’t just transmitted through direct learned and shared experience, but through biological transmission. The study, published in Nature Neuroscience, suggests that our memories may be inherited biologically through chemical changes that occur in the DNA.
Got a Phobia? Perhaps You Inherited It!
The latest research shows that mice can pass on the memories of traumatic and stressful events to their offspring and future generations. Researchers taught mice to fear the smell of cherry blossoms by subjecting them to electric shock whenever the odor was present. After the training was fully integrated and the mice showed fear aversion to the smell of cherry blossom, scientists allowed the mice to breed. From the very first encounter, their offspring exhibited the same fear of cherry blossom odor compared to a neutral odor. The following generation showed the same aversion to the smell of cherry blossoms.
When researchers examined the brains of the mice they discovered that areas responsible for odor detection showed signs of structural alterations, and an examination of their DNA revealed epigenetic methylation (chemical changes) on the gene that detects odor.
What does this mean for humans? It may help shed light on why some people suffer from phobias that appear to have no basis in personal experience. These phobias may be transmitted from ancestral experience before conception.
Dr. Brian Dias, from the department of psychiatry at Emory University, said: “…our results allow us to appreciate how the experiences of a parent, before even conceiving offspring, markedly influence both structure and function in the nervous system of subsequent generations.”
The memories of our parents may increase our risk for neuropsychiatric disorders, such as phobias and anxiety. For example, people with an irrational fear of dogs, without ever having experienced a negative exchange with the animal, may have this fear because they inherited it from a parent.
This latest study indicates that memories are somehow transmitted from the brain, onto the genome, and passed onto offspring. As of yet, scientists don’t know how information becomes stored on the DNA, or if similar effects are indeed exhibited in humans.
Professor Wolf Reik, head of epigenetics at the Babraham Institute in Cambridge, explains: “These types of results are encouraging as they suggest that transgenerational inheritance exists and is mediated by epigenetics, but more careful mechanistic study of animal models is needed before extrapolating such findings to humans.”