Do you get lost a lot? Do you have trouble remembering where you left your keys? Do you have sleep apnea? These things could all be related.
New research indicates that the ability to remember locations and directions may suffer when deep sleep is disrupted by breathing difficulties.
Scientists at New York University who conducted the research say there had been some indication in animal studies that REM sleep or dreaming sleep is important for spatial memory, but no one had shown or proven that in people. Spatial memory helps people remember how to get to the grocery store, or where they left their wallet, for example.
To see whether individuals with sleep apnea tended to have more difficulty forming new spatial memories, the researchers recruited 18 people to spend two nights in their sleep center, about two weeks apart. All 18 volunteers were regular users of continuous positive airway pressure, or CPAP machines. CPAP machines are used to treat sleep apnea by ensuring oxygen is pushed into the body.
During one night in the sleep lab, the research subjects slept with CPAP. The other night, their CPAP was reduced or turned off during deep sleep to induce apnea. On each of the two nights participants were asked to complete a video game maze. The next morning, they completed the maze again. After a night of sleep with their CPAP machine, the time it took the volunteers to complete the maze improved by about 30 per cent. They also traveled farther in the maze and spent less time backtracking. But after a night with sleep apnea, the volunteers were about 4 per cent slower at completing the maze, compared with the night before.
Researchers say they’re not sure if the performance decrease is caused by the disruptions in sleep or the lack of oxygen. Both are results of sleep apnea.