Found : Sharks in the Meme Pool

Memes can produce actual physical sensations. For example, the "God meme" is powerful not only because it has "great psychic appeal" as Dawkins says, (by which he means it economizes thought, explaining many things previously inexplicable); it also can produce strong physical sensations, like euphoria. It even drives people to kill one another. Or consider sexual fantasizing. This can drive people to various states of arousal, and can lead to behaviors that range from harmless to murderous. Being directly linked to genes, sex-related memes are particularly powerful. In both these cases the meme is actually activating other bodily chemicals, be they adrenoline or sex glands. And it may well be that memes — separate from their phenotypic effects — are in fact actual neurochemicals, with access to centers of emotion and motor response in the brain.