Dale Earnhardt Jr. pauses as he talks about missing the next two races with his second concussion in the past six weeks  during a news conference prior to practice for Saturday's NASCAR Bank of America 500 NASCAR Sprint Cup series auto race in Concord, N.C., Thursday, Oct. 11, 2012. (AP Photo/Chuck Burton)

Photo by: Chuck Burton

Dale Earnhardt Jr. pauses as he talks about missing the next two races with his second concussion in the past six weeks during a news conference prior to practice for Saturday's NASCAR Bank of America 500 NASCAR Sprint Cup series auto race in Concord, N.C., Thursday, Oct. 11, 2012. (AP Photo/Chuck Burton)