Four more boys were pulled from a flooded cave in Thailand Monday morning, bringing the total number of boys rescued so far to eight, with four others and their coach still trapped. The rescues come after two weeks trapped underground without sunlight.

"That basically makes your brain act very unusual," Dr. Robert Glatter, an emergency physician at New York's Lenox Hill Hospital, told "CBS This Morning." "You start to hallucinate, you see things, you hear things. You can't really have a sense of who you are."

The boys are all between 11 and 16 years old, and Glatter believes their ages will help a great deal in how they recover.

"Kids of this age are very resilient," Glatter said. "They have a lot of reserve in their heart, their blood vessels. They're able to sustain and withstand stress. In other words, their reserve keeps then going through this. And part of this reserve is actually in their fat stores because what they have are lots of brown fat. And this is metabolically active fat, allowing them to generate heat, because this is exactly what they need to stay alive."

Officials said the rescued boys are being kept in quarantine due to fear of infection.

"In general, the thing they're mainly concerned of is leptospirosis," Glatter said. The CDC says leptospirosis is caused by bacteria found in rodent waste and can lead to kidney damage or meningitis; such infections claimed a number of lives in Puerto Rico after Hurricane Maria.

But Glatter said mental health should be a greater concern.

"In my mind, I think the psychological effects are really more severe at this point," Glatter said. "This is so critical. I think the children need to be hugged, loved. It's so important, the support. They have to understand that their parents are here for them."