Altruism, "Hard-Wired and Pleasurable"?

Scientists, philosophers, and theologians, help us:  How should Catholic legal/social/moral thought respond to this research?  (Registration may be required to view the link.)

The results [of a NIH survey] were showing that when the volunteers placed the interests of others before their own, the generosity activated a primitive part of the brain that usually lights up in response to food or sex. Altruism, the experiment suggested, was not a superior moral faculty that suppresses basic selfish urges but rather was basic to the brain, hard-wired and pleasurable.

Their 2006 finding that unselfishness can feel good lends scientific support to the admonitions of spiritual leaders such as Saint Francis of Assisi, who said, "For it is in giving that we receive." But it is also a dramatic example of the way neuroscience has begun to elbow its way into discussions about morality and has opened up a new window on what it means to be good. . . .

The research enterprise has been viewed with interest by philosophers and theologians, but already some worry that it raises troubling questions. Reducing morality and immorality to brain chemistry -- rather than free will -- might diminish the importance of personal responsibility. Even more important, some wonder whether the very idea of morality is somehow degraded if it turns out to be just another evolutionary tool that nature uses to help species survive and propagate.

Can one dispel those worries, and be comfortable with the results of this research, if one gives a natural-law account of morality, e.g.: (1) Fundamental morality consists in certain natural-law principles "written on the heart"; (2) the evolution of brain chemistry is the mechanism by which the Creator inscribed the principles in us; and (3) the principles are teleological in the sense of promoting human flourishing?  That answer tries to affirm the natural, material element in morality while insisting that it's logically fallacious to reduce morality therefore to the material.

One obvious difficulty with this reconciliation is that the goal of survival/propagation and the goal of "human flourishing" typically described in moral theory seem very different, even if they sometimes coincide.  Plus we seem to be hard-wired for selfishness in various ways as well, so the mere fact of hard-wiring won't necessarily tell us much about the distinctive moral sense.  I'm sure there are other challenges and answers as well, but I'd be interested in hearing from others who know more about these matters than I.

Tom