Research Paper Title

Neural correlates of dynamic changes in working memory performance during one night of sleep deprivation.

Background

Total sleep deprivation (TSD) is common in modern society leading to deterioration of multiple aspects of cognition.

Dynamic interaction effect of circadian rhythmicity and homeostatic sleep pressure on sustained attention have been intensively investigated, while how this effect was represented on performance and cerebral responses to working memory, another important element of many neurobehavioural tasks, was not well elucidated.

Methods

Thirty-six healthy subjects with intermediate chronotype performed the Sternberg working-memory task (SWMT) while undergoing functional magnetic resonance imaging every 2 hr from 10:00 p.m. on the first day to 6:00 a.m. on the second day.

Results

Using data from three imaging sessions (10:00 p.m., 04:00 a.m., and 06:00 a.m.), the researchers found that the slowest SWMT reaction time and weakest cerebral responses were not at the end of TSD (06:00 a.m.) but during the early morning (04:00 a.m.) hours of the TSD.

In addition, during this worst period of TSD, reaction time for the SWMT were found to be negatively correlated with task-related activation in the angular gyrus and positively correlated with the degree of negative correlation between the control and default networks.

Conclusions

The results revealed a rebound of SWMT reaction time and cerebral responses after the mid-time point of regular biological sleep night and provided more evidence that different cognitive tasks are differentially affected by sleep loss and circadian rhythmicity.

Reference

Zhu, Y., Xi, Y., Sun, J., Guo, F., Xu, Y., Fei, N., Zhang, X., Yang, X., Yin, H. & Qin, W. (2019) Neural correlates of dynamic changes in working memory performance during one night of sleep deprivation. Human Brain Mapping. 40(11), pp.3265-3278. doi: 10.1002/hbm.24596. Epub 2019 Apr 10.