Studies show that there is a strong link between sleep and memory. A new study even examines how sleep affects memory for face identity. Does sleep help you recognize a familiar face?
The study involved 112 volunteers; their average age was 25 years. Each participant was shown 60 computer-generated faces in random order.
The heads were bald, and the faces had no unique features such as a mole or a scar. Each face was shown on a computer screen for two seconds at a time. The entire set of faces was shown five times.
Recognition was tested after varying periods of time. Some people were tested after getting sleep; others were tested before getting any sleep. Sixty faces were shown; 30 faces had been seen earlier, and 30 were new faces that had never been seen before.
The results do not show that sleep enhances memory strength. But they do suggest that time spent awake during the retention period impairs memory for face identity.
Wakefulness of 12 hours or more had a detrimental impact on recognition memory strength; it made participants less likely to feel familiar with a test face.
The authors suggest that ongoing sensory stimulation when awake may interfere with visual memory. Sleep may not actively enhance visual memory; but it may temporarily prevent memory loss by “sheltering” visual memory from interference.
Read the full text of the study online.