I'm not familiar with the biochemistry involved or what exactly "ΔFosB expression" means, and I don't know if the term "addiction" is used in its strictly techn

I'm not familiar with the biochemistry involved or what exactly "ΔFosB expression" means, and I don't know if the term "addiction" is used in its strictly technical definition here (i.e activating the reward circuit) or if it's used to generally mean some form of dependence... but it's worth noting that caffeine dependence is pretty common.