Phosphorous31 magnetic resonance spectroscopy after total sleep deprivation in healthy adult men.

STUDY OBJECTIVES

To investigate chemical changes in the brains of healthy adults after sleep deprivation and recovery sleep, using phosphorous magnetic resonance spectroscopy.

DESIGN

Three consecutive nights (baseline, sleep deprivation, recovery) were spent in the laboratory. Objective sleep measures were assessed on the baseline and recovery nights using polysomnography. Phosphorous magnetic resonance spectroscopy scans took place beginning at 7 am to 8 am on the morning after each of the 3 nights.

SETTING

Sleep laboratory in a private psychiatric teaching hospital.

PARTICIPANTS

Eleven healthy young men.

INTERVENTIONS

Following a baseline night of sleep, subjects underwent a night of total sleep deprivation, which involved supervision to ensure the absence of sleep but was not polysomnographically monitored.

MEASUREMENTS AND RESULTS

No significant changes in any measure of brain chemistry were observed the morning after a night of total sleep deprivation. However, after the recovery night, significant increases in total and beta-nucleoside triphosphate and decreases in phospholipid catabolism, measured by an increase in the concentration of glycerylphosphorylcholine, were observed. Chemical changes paralleled some changes in objective sleep measures.

CONCLUSIONS

Significant chemical changes in the brain were observed following recovery sleep after 1 night of total sleep deprivation. The specific process underlying these changes is unclear due to the large brain region sampled in this exploratory study, but changes may reflect sleep inertia or some aspect of the homeostatic sleep mechanism that underlies the depletion and restoration of sleep. Phosphorous magnetic resonance spectroscopy is a technique that may be of value in further exploration of such sleep-wake functions.