Harvin is seeing a specialist for his condition, which Childress called "debilitating." The first-round draft pick is second on the team with 681 yards and six touchdowns receiving entering Sunday's game at Carolina.
Harvin also is second in the NFL in kickoff returns with a 29-yard average and has brought back two for touchdowns.
"It's kind of an abstract thing right now," Childress said. "We know that he gets headaches. We don't know the whys and what-fors."
Copyright 2009 by The Associated Press