Q: Could memories and feelings be passed from generation to generation in DNA? I grew up in Alabama. The first time I came West I was 21 years old and I knew I was coming “home.” Yet I had never been in this area. The first time I heard Native American chanting and music, it was already in my soul. I do have a great great great grandmother that was Cherokee Indian. Not much known about her and I was not raised with this knowledge. Could this be similar to “déjà vu,” that feeling you’ve “been there before” whe you know you could not have? – Jill, Golden, Colorado
A: Dear Jill,
Let’s start with déjà vu and reduce the complexity of your question a bit. Déjà vu is the illusion that you’ve experienced something before when in fact you are encountering it for the first time. Most of us experience this on occasion. In the movie The Matrix, the phenomenon was attributed to a glitch in, well, the Matrix.
Most scientifically-minded professionals might tell you that’s not too far from the truth, except that the matrix in question is the one inside your skull; déjà vu has been attributed to neurological hiccups of a sort in your frontal lobes (Brown, 2004). The explanations can get fairly complex, so we’ll save that for another day and get to the heart of your question: could great, great, great grandma’s memories be traveling in your DNA? Those same scientifically-minded professionals would tell you: probably not. Such an unimaginative bunch they are. Let’s hear them out, though, shall we? Starting with me.
In my essay on memory, I tried to point out the difference between memories, the noun, and remembering, the verb. Current evidence suggests that human memory does not really exist in DNA or other chemicals (though they are essential), but rather in the arrangement of neurons. Think of a gasoline engine. The torque that comes out the back end of an engine does not exist in the gasoline, or the pistons, or the crankcase. It is a product of relationships between parts and energy.
Similarly, memory is not something we have so much as something we do. We couldn’t do memory if we didn’t have the right parts in the right order to begin with, and that’s where genetics and DNA come in. Steven Pinker (1999) compared DNA to the blueprints of a building. Blueprints (or DNA) contain instructions for every detail of a building (or a body). What you do with the building (or the body) after it’s built is up to you. It doesn’t come furnished.
One of the things DNA does is create structures that predispose us to behaviors – like eating and talking and remembering things. However, there’s no evidence I’m aware of to suggest that DNA builds neural arrangements that lead to specific memories. DNA just creates the unfurnished building, so to speak.
Epi-What?
But here’s something you might find interesting, Jill: there’s more than one way that genes can be expressed. Epigenetics, a burgeoning field of genetic inquiry, looks at the ways in which environment can affect DNA and thereby shape the way you look and act.
Let’s say that your grandmother had a difficult pregnancy when she was carrying your mother in her womb – long after your mother’s DNA had been permanently established. That experience could affect not only your mother’s physical growth (changing the way DNA was expressed), but yours as well (Harper, 2005). Environment can alter the expression of DNA like lighting can alter the appearance of a painting: same image, different look. When your mother’s gene expression was altered during the difficult pregnancy, that altered expression could have been passed on to you.
You might reasonably view this as a means of transferring information from one generation to the next. In this case, the message might be: grandma had a rough pregnancy. There is also some evidence that this is how temperament and personality traits get passed from parent to offspring (Carere, Drent, Koolhaas, & Groothuis, 2005).
Could other information be relayed too, such as great, great, great grandmother’s ties to a particular landscape? Or her recollection of a certain type of music or chanting?* The scientist in me says that there’s no evidence that genetic information, or variability in genetic expression, extends so far as to carry specific memories. But that scientist in me is a mouthy one. Sometimes the romantic in me wants to believe in a higher order of things. After all, what we don’t know about ourselves and the universe far outweighs what we do know.
Though the Iron Shrink is certainly no expert in religion, I have heard that Cherokee spirituality speaks of a specific kind of reincarnation in which animals, including us humans, can be reborn multiple times. With each incarnation the essence of the previous animals is carried forward until it is time for that spirit to move to the Darkening Land. Does that sound a teensy bit similar to epigenetic expression? I’ll let you draw your own conclusions, but it’s enough to give me pause.
-IS
* In your question you stated that moving west felt like “coming home.” For your Cherokee ancestors, home probably would not have been the West, but what is now the Southeastern U.S., especially the area around your home state of Alabama. However, that doesn’t mean you didn’t have ancestors in the West, as well.
References:
Brown, A. S. (2004). The deja vu illusion. Current Directions in Psychological Science, 13(6), 256-259.
Carere, C., Drent, P. J., Koolhaas, J. M., & Groothuis, T. G. G. (2005). Epigenetic effects on personality traits: Early food provisioning and sibling competition. Behaviour, 142(9-10), 1329-1355.
Harper, L. V. (2005). Epigenetic inheritance and the intergenerational transfer of experience. Psychological Bulletin, 131(3), 340-360.
Pinker, S. (1997). How the Mind Works. New York: Norton.