Oliver Sacks and the blitz of London. His brother later told him that this had not happened to Oliver, and indicated that the event originated in a letter written by their older brother. Sacks described that the mental image for the event continued to resemble other vivid memories, despite the knowledge that the memory was not true. NBMs are interesting because they challenge the assumption that vivid memories are accompanied by the belief that memories are veridical. The existence of NBMs requires rethinking the relationship between recollective experience and belief in the occurrence of autobiographical events, a distinction first proposed by Mazzoni and Kirsch (2002)