Memory

Memories were the mental record of a lifeform's past experiences.

Jamie McCrimmon and Zoe Heriot's memories of their time with the Second Doctor where erased by the Time Lords before they were returned to their original times. (TV: The War Games)

The Tenth Doctor had to erase Donna Noble's memories of their travels together, to save her mind from being overwhelmed by the Time Lord knowledge she gained from the meta-crisis. (TV: Journey's End)

A memory worm could suppress recent memories, causing short-term amnesia. (TV: The Snowmen, Time Heist)

Clara Oswald read the Doctor's name in The History of the Time War. When that timeline was later averted, however, she had no memory of it. (TV: Journey to the Centre of the TARDIS)

Retcon was a drug used by Torchwood to remove memories of the organisation and/or alien encounters from witnesses. (TV: Everything Changes, Adam, They Keep Killing Suzie, Meat, Something Borrowed, COMIC: Shrouded)