Cages line the wall stacked on top of one another. Most of the monkeys lay unmoving, enervated and sunken. Almost all have recording apparatuses attached to their skulls—after being anesthetized the monkey is scalped, the top of the head removed to bare the skull. Then the skull is softened, a portion removed, and an open grating is installed through which the scientist can peek in at the brain. Finally this grating is sealed from above with a removable cap, to provide easy access, and a kind of plastic concrete is spread over the naked skull to cover it and support the recording chamber. Eventually electrodes can be lowered during behavioral experiments to listen to the pop-pop talk of neurons. The monkeys thus wear crowns of concrete, often with blood or pus ringing the annulate barrier where the skin meets the installment, with little plastic caps at the summit like miniature chimney tops that can be unscrewed.

“What are those?” Kierk asks, pointing to reams of crumpled tinfoil in several bins.

It’s a veterinarian who answers. “The city is always generating electromagnetic background noise. To keep it from influencing the data we wrap their heads with tinfoil during the sessions.”

“You make them wear tinfoil hats?”

“How come some of the monkeys have problems with their hands?” Jessica asks, and Kierk notices what she’s talking about—the monkeys palm the floor with flat hands, try to scoop up their toys with their wrists.

It’s Atif who answers from across the room in his deep voice—“Because the recording chamber is at the top of their head. Often right over their primary motor cortex. And since you keep moving a needle down through it . . .” He makes repeated stabbing motions.

“Oh!” Jessica’s eyes widen.