Benedict Carey of the New York Times sure does like using metaphors to describe science stuff.
At least, that's the conclusion I draw from reading his article Brain Researchers Open Door to Editing Memory. It's an interesting article on an interesting topic, but I got a little distracted by the blend of metaphors for brain activity.
The article's main metaphor is introduced here:
[...] brain cells activated by an experience keep one another on biological speed-dial, like a group of people joined in common witness of some striking event. Call on one and word quickly goes out to the larger network of cells, each apparently adding some detail, sight, sound, smell.
So far, so good. But then a few paragraphs later, things get a little out of hand:
In a series of studies, Dr. Sacktor's lab found that [the molecule PKMzeta] was present and activated in cells precisely when they were put on speed-dial by a neighboring neuron.
In fact, the PKMzeta molecules appeared to herd themselves, like Army Rangers occupying a small peninsula, into precisely the fingerlike connections among brain cells that were strengthened. And they stayed there, indefinitely, like biological sentries.
In short: PKMzeta, a wallflower in the great swimming party of chemicals that erupts when one cell stimulates another, looked as if it might be the one that kept the speed-dial function turned on.
Good thing we've got all those wallflower sentry Army Rangers to keep the speed-dial running.