A deficit in the ability to form new human memories without sleep

Seung-Schik, Y., Hu, P. T., Gujar, N., Jolesz, F. A., & Walker, M. P. (2007). A deficit in the ability to form new human memories without sleep. Nature Neuroscience, 10(3), 385-392. Retrieved October 11, 2011, from Academic Search Premier. doi:10.1038/nn1851

This study was conducted using an fMRI design to explore the capability of the brain to create new episodic memories without prior sleep. This study was composed of 28 participants who were randomly assigned to a sleep-deprived or a sleep control group. All participants had a encoding session for episodic memory during fMRI scanning where they viewed picture slide. They returned two days later in order to classify the pictures they saw again as old or new slides. Researchers hypothesized that one night of being sleep deprived would significantly decrease the subjects’ ability to encode memory and that the impairments would be related to neural deficits in the medial temporal lobe memory systems. Past studies have shown that obtaining sleep after learning is important in order for its consolidation into memory.. The question of whether sleep before learning is as important when forming new memories is still open for discussion. The researchers did find that there was a considerable decline in the activity of the hippocampus when episodic memory was encoding which resulted in worse retention. The researchers also found that the prefrontal regions play a major role in predicting the encoding ability of individuals who have been deprived of sleep in contrast to those who have had a normal night’s sleep. From these results it can be gathered that inadequate sleep can compromise an individual’s neural and behavioral ability to commit new occurrences into memory. Sleep is definitely critical when it comes to encoding new memories after learning and it is also just as important before learning when it comes to prepping the brain for memory formation in the upcoming day.