How does Resch say it is possible for an android to kill himself?

From chapter 12--- they can kill themselves by holding their breath.

"How'll you kill yourself without it?" Rick asked. "If you fail on the test?"

"I'll hold my breath."

"Chrissake," Rick said. "It can't be done."

"There's no automatic cut-in of the vagus nerve," Phil Resch said, "in an android. As there is in a human. Weren't you taught that when they trained you? I got taught that years ago."