Atwood has used memory in this novel as a form of escape for the main character 'Offred' or 'June' as some critics believe her to be called. Mostly, memories are used when Offred is alone in her room, therefore, the majority of memories occur in the 'Night' sections.
The reason Offred only permits memories when she is own her own is because she doesn't want to let any emotion show around other people. This can be seen in the kitchen when Offred smells bread baking and this lead her into more memories of home and she stops herself while she is in the presence of others.
However, once Offred is alone, she allows herself to drift, before Offred remembers some key memories, she asks herself "where should I go?" As if, for a short space of time, Offred can go, or do, anything she likes. However, she does remind herself "this is time, nor am I out of it."
This is a play on a line from 'Dr. Faustus' By saying this, Offred is stopping herself from getting carried away.
Atwood also uses memories so that multiple pasts can be explored at once. During the novel, we are taken back to many different times in the past, when Offred was a child, her time with Luke, her mother and her best friend Moira, also the time when she was training to be a Handmaid. Atwood may have used this method to make the novel more interesting, but also, it enforces the fact that the novel is a first person narrative, and as we find out in the Historical Notes, has all been remembered sometime after it all happened. The time can shift years in just a few words, and this choppy method keeps readers hooked, and is...