Interrupted Sleep Could Impair Forming Memories

Uninterrupted sleep is the key to getting the right amount of rest. It not only helps physically, but mentally. In a new study, researchers at Stanford University discovered that sleep interruptions impair the brain’s ability to form memories.

Scientists assumed that memory would become hindered because of a lack of sleep continuity. Memory problems can be seen in people who suffer from alcoholism or sleep apnea. Both of these problems can cause sleep discontinuity.

The problem researchers faced was finding a way to break sleep into shorter segments without affecting the intensity or duration of sleep. The solution: optogenetics. This is a new technique that can genetically engineer specific cells to be able to be controlled by visible light pulses. Researchers performed this method on the neurons of the brain that help it switch between sleep and wakeful states.

Using mice as test subjects, researchers found that by hitting the rodents’ brain cells with 10-second bursts of light; they could break up their sleep without affecting the intensity or duration of the sleep.

After the test was completed, the mice were then given two objects. One was familiar while the other object was new to the mice. After interrupted sleep, the mice took just as long to investigate the familiar object as the new one. The mice spent more time with the new object when their sleep was not interrupted.

After testing different variations of sleep interruption, the researchers concluded that if the mice were allowed 62-73% of the normal sleep duration, it would not affect memory. Study co-author H. Craig Heller, professor of biology at Stanford University, believes that the findings show that sleep continuity is critical for memory.

It remains unclear how much uninterrupted sleep is needed to prevent memory impairment in humans. The researchers did say however that the memory problems experienced by people with sleep disorders are most likely due to disruption of continuity in their sleep.

Photo by: Tim Snell