question:  What has conditioning done to the characters?
context: When nobody aboard ship remembers where it's going, how can they tell when it has arrived? But ever since the engines somewhere in the rear of the world had changed their tone, from the steady whining Rikud had heard all twenty-five years of his life, to the sullen roar that came to his ears now, the feelings had grown. Rikud knew that something which he could not explain had entered the elder man's head for a moment, but it had departed almost before Chuls knew of its existence. But something soft had cushioned the impact—something which had come into being just for the moment and then abruptly passed into non-being again, something which was as impalpable as air. Rikud had been stopped in this action, although there was no real authority to stop him. There had been a revolt—again a term without any real meaning, a term that could have no reality outside of the reading machine—and the elders were overthrown. The people had decided that they did not know where they were going, or why, and that it was unfair that the elders alone had this authority. They were born and they lived and they died as the elders directed, like little cogs in a great machine. True, this was the only case of its kind, the exception to the rule, but it proved the world was not perfect. You can find several of them under 'astronomy,' with a cross-reference under 'stars.' "Variability," he told them, "is a contradictory term. Variability and change are two words without meaning." But how could a star change into a blinking blue-white globe—if, indeed, that was the star Rikud had seen earlier? Except that it was variable, which was like change, being tied up somehow with age. A section of it had expanded outward and assumed the rectangular shape of the viewport, and its size as well.
output:  It has become a way of life for them. Without the buzzer, their life as they know it ceases to exist.
options:  It has kept them in shape, both mentally and physically,  and ready to face the struggles they encounter.  Nothing.  They were left to their own devices for so long that they abandoned any notion.  It has made them fear one another.  It has become a way of life for them. Without the buzzer, their life as they know it ceases to exist.