Doctor Clendenning was a Human scientist of the 24th century. In the 2330s, he resided in the Omicron Theta colony. His research involved new methods of detecting gamma radiation.

As part of Dr. Noonian Soong's work, Clendenning was one of many colonists whose experiences and memories were partially implanted into Data. This included experiences Clendenning had not been yet able to record.

Clendenning was working on new detectors in 2338, when the Crystalline Entity attacked the colony and killed its inhabitants including Clendenning.

By 2368, Kila Marr was familiar with his records, but had never read about the gamma scans. The knowledge of his work made it possible for the USS Enterprise-D to detect the antiprotons the Crystalline Entity left behind when travelling through space. (TNG: "Silicon Avatar")

This character was only mentioned in dialogue.