Just to clarify... personally, I take Chazal literally and I have no problems dealing with their model of the human psyche including their conceptualization of the heart as a source of emotion.
For those who feel the need to reconcile with science, I cannot relate. However, as the world gets closer to Moshiach I am sure that science will catch up. For those who are into this kind of thing, I think that possibly the understanding of the role of the vagus nerve may hold a lot of the answers.