Pat Long is a journalist at the Times and the Sunday Times. He is currently writing a book about his experience of brain cancer and its effect on memory and personality. You can find him on Twitter @PatLongTweets
Five quirks of memory that can mess with your sense of reality.
When a brain tumour left Pat Long with persistent déjà vu, he began to question the very nature of reality. Here, he tells his story for the first time.