Last month, I watched this video of ELO miming to "Can't Get It out of My Head" on Dutch television:
I noticed that in one of the Moog phrases (at ~1:21 in the video, but at ~2:27 in the album version), there are some trills. Despite what it looks like in the video, I think these notes are E F E, C D C, G A G, E F E.
These descending trills may have been modeled after part of the solo in Del Shannon's "Runaway" (performed on a heavily modified clavioline). Jeff Lynne talks about the song (starting around 39:14) in this BBC interview. He mentions that the tape was sped up, so while it sounds higher, originally, these trills were played as E F E, D E D, C D C. Obviously, in terms of pitch, these groups of notes are closer to each other than those in "Can't Get It out of My Head," but they do descend.
