Washington ? Science is reshaping the argument about whether nature or nurture is decisive in determining human destinies, and about what the answer means for social policy. Consider a fascinating new report arguing the scientific evidence for the importance of “authoritative communities” — groups, religious or secular, devoted to transmitting a model of the moral life.

The report is from the 33 research scientists, children’s doctors and mental health and youth services professionals comprising a commission jointly sponsored by the Dartmouth Medical School, the Institute for American Values and the YMCA of the USA. The report’s conclusion is in its title: human beings are “Hardwired to Connect.”

In an era of increasing prosperity, the evidence of children’s failures to thrive — depression, anxiety, substance abuse, conduct disorders — is also increasing. Pharmacological and psychotherapeutic responses to such deteriorating mental and social health are necessary but insufficient. Also needed is recognition of how environmental conditions — the social environment — contribute to childhood suffering.

The problem is a deficit of connectedness. The deficit is the difference between what the biological makeup of human beings demands and what many children’s social situations supply in the way of connections to other people, and to institutions that satisfy the natural need for moral and spiritual meaning.

The need expresses itself in religious cravings — the search for moral meaning and an openness to the possibility of a transcendent reality. The need is natural in that it arises from “our basic biology and how our brains develop.” The report draws upon the science of infant attachment, and of brain development, particularly during adolescence, when the brain changes significantly.

The report argues that our understanding of children’s difficulties is thwarted by the assumption that each child’s problems are exclusively personal and individual, thereby ignoring social and communal factors. In fact, the report argues that we are “biologically primed” for finding meaning through attachments to others.

The need for meaning is increasingly discernible in the basic structure of the brain. “The idea,” says Allan N. Schore of the UCLA School of Medicine, “is that we are born to form attachments, that our brains are physically wired to develop in tandem with another’s, through emotional communication, beginning before words are spoken.”

Furthermore, the report says, social environments that meet — or defeat — this need “affect gene transcription and the development of brain circuitry.” And “a social environment can change the relationship between a specific gene and the behavior associated with that gene.” A child’s “relational context,” says Schore, “imprints into the developing right brain either a resilience against or a vulnerability to later forming psychiatric disorders.”

“The biochemistry of connection” will seem too, well, deflating for some people’s comfort. The report cites, for example, another study that says oxytocin, a hormone, enters a woman’s bloodstream during sexual intercourse, childbirth and lactation, promoting, the report says, “emotional intimacy and bonding (also sometimes known as ‘love’).” In men, marriage — sexual and emotional intimacy with a spouse — seems to lower testosterone levels, thereby lowering the “biological basis for violent male behavior and male sexual promiscuity.”

So biology, it seems, buttresses important moral conventions. And they may have evolved in conformity to biological facts.

The scientific fact, if such it is, that religious expression is natural to personhood, does not vindicate any religion’s truth claims. A naturalistic hypothesis is that the emotions of religious experience have neurobiological origins: The brain evolved that way to serve individual and group survival.

In any case, the social utility of religion remains. And there may be a biological basis for religious affiliation reducing the risk of certain pathologies, and even enhancing immune systems.

The most basic authoritative community, the family, is the most crucial. Its decline weakens the other institutions of civil society. The result is a thinness of social connectedness, and what Tocqueville warned was a risk of American individualism — each person confined “entirely within the solitude of his own heart.”

“Hardwired to Connect” suggests that there is no simple “versus” in “nature versus nurture.” There is a complex interaction, which means, among many other important things, that IQ is not a simple genetic inheritance, it is a function of that inheritance and the influence on it of a context of connections.

The implication for governance is that social policies should foster the health of authoritative communities, especially given the fact that the yearning for such communities among adolescents often takes the form of gang membership. And evidently the Bush administration’s belief in the wisdom of delivering social services through faith-based institutions is not just a matter of faith.