neocortex

Now that we’ve pretty much established that sleep is crucial for consolidating memory, the next question is how much sleep we need.

A new study compared motor sequence learning in 16 people with mild obstructive sleep apnea to a matched control group (also attending the sleep clinic). There were no significant differences between the groups in total sleep time, sleep efficiency and sleep architecture (time spent in the various sleep stages), subjective measures of sleepiness, or performance on a psychomotor vigilance task (a task highly sensitive to sleep deprivation).

When a middle-aged woman loses her memory after sex, it naturally makes the headlines. Many might equate this sort of headline to “Man marries alien”, but this is an example of a rare condition — temporary, you will be relieved to hear — known as transient global amnesia. Such abrupt, localized loss of autobiographical memory is usually preceded by strenuous physical activity or stressful events. It generally occurs in middle-aged or older adults, but has been known to occur in younger people. In those cases, there may be a history of migraine or head trauma.

The role of sleep in consolidating memory is now well-established, but recent research suggests that sleep also reorganizes memories, picking out the emotional details and reconfiguring the memories to help you produce new and creative ideas. In an experiment in which participants were shown scenes of negative or neutral objects at either 9am or 9pm and tested 12 hours later, those tested on the same day tended to forget the negative scenes entirely, while those who had a night’s sleep tended to remember the negative objects but not their neutral backgrounds.