Given all the research showing the importance of sleep for consolidating memories, it should come as no great surprise that the reverse is also true: depriving yourself of sleep could help you forget experiences you would prefer not to remember.
In the study, 28 student volunteers were shown 14 short video clips, half of which showed safe driving down a city street, and half showed the car being involved in a nasty crash. Half of the volunteers were then deprived of sleep while the other half received a normal night's sleep. The next day, they were shown pictures and asked to indicate whether they had appeared in the clips they had seen. They were also asked to rate the fear evoked by the image, and their physiological responses measured. They were tested again 3 and 10 days later.
While there was no difference between the two groups in picture recognition, the control group rated the images from the crash videos as fearful, and these responses generalized over time to the other images. However, those who were sleep deprived showed such reactions only on the first day.
The finding suggests a possible therapy for PTSD or other anxiety disorders.
(2010). Sleep Deprivation Facilitates Extinction of Implicit Fear Generalization and Physiological Response to Fear.
Biological Psychiatry. 68(11), 991 - 998.