Ben Carson's newfound status as a front-runner for the GOP's 2016 presidential nomination has forced the retired neurosurgeon to put in long hours to catch up on the complexities of U.S. foreign policy.

The physician's comments on international issues have raised eyebrows in the past. Duane Clarridge, a former CIA Agent and one of Carson's top advisers on terrorism and national security, told The New York Times the 64-year-old still has difficulties mastering the intricacies of the Middle East and national security, in spite of the intense tutoring he is receiving.

"Nobody has been able to sit down with him and have him get one iota of intelligent information about the Middle East," Clarridge said.

"Sometimes he overthinks things," added Armstrong Williams, Carson's longtime business manager and his campaign's top counselor.

The presidential hopeful's troubles were on display on Sunday, when he was unable to tell "Fox News Sunday" host Chris Wallace whom he intended to call first to form a coalition against the ISIS jihadist group in the wake of the Nov. 13 terrorist attacks on Paris.

"We need to have a conference call once a week where his guys roll out the subjects they think will be out there, and we can make him smart," Clarridge said he told Williams, who in turn admitted that the Fox News interview "was a bummer for [Carson]."

But Williams said he was optimistic about the candidate's learning curve, insisting that the newcomer was making progress, according to The Associated Press.

"I'd say he's 75 percent of the way there," Williams said. "The world is a complex place, and he wants to get it right."

Carson himself, meanwhile, likened his foreign policy training to his medical education. He revealed that he spends considerable time reading materials and maintaining discussions with experts with diplomatic and military backgrounds, The AP added.

"It's an ongoing process," he told Des Moines' WHO-TV. "In medicine, we have something called CME -- continuing medical education -- that recognizes that you never become a know it all, you always are continuing to learn."