This is—to say the least—a sub-optimal learning environment. To be slightly more scientific, in this scenario you have a roomful of people who are ether essentially or entirely disengaged from their prefrontal cortex (PFC)—the part of the brain responsible for cognitive functions.
Kerry Mensior—a retired law enforcement veteran with three decades on the job and now executive director of the International De-Escalation Association (IDEA)—says, "Your brain can only be in one of two states. It can be in 'executive state' or it can be in 'survival state.' When you're in 'executive state,' [you're using] your prefrontal cortex (PFC)—that's the thinking, logical, reasoning part of your brain. When you're in 'survival state,' that part of your brain is turned off."
When the PFC is engaged, a student in a classroom can connect with the other students. They can interact with and learn from the other people in the class as well as the trainer. The brain in the executive state can take in the information that's being presented and is able to effectively store that information for recall later. When a person is in 'survival state,' they can't do any of those things.
Mensior says that some researchers contend that humans spend between 70% and 80% of their life in the survival state of brain activity. He says that understanding and accounting for this is essential for trainers to successfully train their students.
"If you have students that are hostages in your classroom—it's mandated training, and they really don't want to be there—you immediately know that their brain is in survival state," he says.