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Missile Defense

Russian military leaders have expressed concern about US plans for a national missile defense system. Will defense technology be limited by possibilities for a strategic imbalance? Is this just SDI all over again?

rshowalter - 10:56am Apr 28, 2001 EST (#2702 of 2707)
Robert Showalter showalte@macc.wisc.edu

Weinberger continues:

" Many factors can impair the capacity of the prefrontal cortex to serve its full impulse-control function: for example, neurological diseases that kill cells in the prefrontal cortex, head injuries that damage these cells, alcohol and drugs that impair their function, and biological immaturity.

"The inhibitory functions are not present at birth; it takes many years for the necessary biological processes to hone a prefrontal cortex into an effective, efficient executive. These processes are now being identified by scientific research. They involve how nerve cells communicate with each other, how they form interactive networks to handle complex computational tasks and how they respond to experience. It takes at least two decades to form a fully functional prefrontal cortex.

" Scientists have shown that the pace of the biological refinements quickens considerably in late adolescence, as the brain makes a final maturational push to tackle the exigencies of independent adult life. b But the evidence is unequivocal that the prefrontal cortex of a 15-year-old is biologically immature. The connections are not final, the networks are still being strengthened and the full capacity for inhibitory control is still years away.

( Odds are good, that in the population of personnel controlling nuclear weapons, there are immature prefrontal cortices, as well. )

" The 15-year-old brain does not have the biological machinery to inhibit impulses in the service of long-range planning. This is why it is important for adults to help children make plans and set rules, and why institutions are created to impose limits on behavior that children are incapable of limiting. Parents provide their children with a lend-lease prefrontal cortex during all those years that it takes to grow one, particularly when the inner urges for impulsive action intensify.

( None of us, as animals, are "adult" enough to handle nuclear weapons. What might Bob Kerrey, a good animal, have done, under great stress, if he'd had a nuclear weapon ? What might you, or many people you know do ? )

" Adolescents have always had to deal with feeling hurt, ashamed and powerless. In the face of ridicule, they may want revenge. Thirty years ago, a teenager in this position might have started a fight, maybe even pulled a knife. If he was afraid that he could not defend himself, he might have recruited a tough guy to help him out. One way or another, he would have tried to teach his tormentors a lesson. Very likely, however, no one would have died.

" But times have changed, and now this angry teenager lives in a culture that romanticizes gunplay, and he may well have access to guns.

( And military forces, trained to maximize force, have nuclear weapons. )

" I doubt that most school shooters intend to kill, in the adult sense of permanently ending a life and paying the price for the rest of their own lives. Such intention would require a fully developed prefrontal cortex, which could anticipate the future and rationally appreciate cause and effect. The young school shooter probably does not think about the specifics of shooting at all. The often reported lack of apparent remorse illustrates how unreal the reality is to these teenagers.

( The same can be said of bombing crew. And would be true of button pushers. )

" This brief lesson in brain development is not meant to absolve criminal behavior or make the horrors any less unconscionable. But the shooter at Santana High, like other adolescents, needed people or institutions to prevent him from being in a potentially deadly situation where his immature brain was left to its own devices. No matter what the town or the school, if a gun is put in the control of the prefrontal cortex of a hurt and vengeful 15-year-old, and it is pointed at a human target, it will very likely go off.

( Gorbecheve made a related point, when he said, wi

rshowalter - 10:58am Apr 28, 2001 EST (#2703 of 2707)
Robert Showalter showalte@macc.wisc.edu

( Gorbecheve made a related point, when he said, with respect to nuclear weapons, that "Even an unloaded gun goes off every once in a while. ... )

Daniel R. Weinberger is director of the Clinical Brain Disorders Laboratory at the National Institutes of Health.