Mammals’ experiences – our experiences – can cause hormones to be released in our bodies, and these molecules can then move into the vicinity of DNA, where they can produce epigenetic effects. Our environments also influence our internal states by stimulating our sensory organs; seeing and hearing, for example, both produce changes in our bodies that can have epigenetic consequences.

   Because stimulation arising in the environment can affect biological activity at several levels – at the level of the neurons in our sensory organs, at the level of the hormones in our bloodstreams, at the level of genes in our cell nuclei - an essential part of how we come to be as we are, will always be what we experience, that is, in contexts that our minds, bodies, cells, organs, and genes find themselves in.