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Show She does not answer, and he begins again to explain. "What we're trying to find out is what patterns of electrical activity occur in the brain during certain types of conditioning or learning. So we have electrodes implanted in the dog's brain, and then we record the population of neural cells which fire while the dog is being conditioned." Boaz must have watched her as he talked; he must have noticed how small a girl she is, small and slender, made smaller by the large swivel chair. Perhaps she Was wearing her thin black hair free that day, or perhaps it was knotted up with a long paisley scarf, but surely Boaz must have noticed her eyes: wide eyes rimmed in black mascara, eyes so wide she looked as if she might cry at any moment. "Each dog spends an hour in the experimental box every third day, learning how to react to a given stimulus situation. It will take the dogs maybe three or four months, maybe longer, to complete their conditioning, and then -" He hesitates, watching her wide eyes. She looks at him, saying nothing. "Stereotaxic implantation is very difficult," he says distantly, "because you never can be sure just where the electrodes are." She sits silent, listening. "An electrode is nothing but a piece of conductive wire, inserted directly into the brain through a tiny hole bored in the skull. The shaft end is cemented to a terminal for the monitoring equipment, called a pedestal, and the pedestal itself is affixed to the skull directly over the cortex region. The pedestal anchors the electrodes, and -" |