"FILE - This Jan. 27, 2013 file photo shows Dick Van Dyke on stage at the 19th Annual Screen Actors Guild Awards at the Shrine Auditorium in Los Angeles. Van Dyke is undergoing tests for ""cranial throbbing"" that's causing him to lose sleep. Spokesman Bob Palmer said Thursday the 87-year-old Van Dyke has been experiencing a throbbing sensation in his head when lying down. Scans and other tests have yet to yield a diagnosis, Palmer said. (Photo by John Shearer/Invision/AP, file)"