Staying awake for 21 hours causes a measurable drop in brain energy levels in young healthy people, with the phosphocreatine to inorganic phosphate ratio decreasing by nearly 5%, which shows the brain is working harder and using more energy when sleep-deprived.
Scientific Claim
Sleep deprivation for 21 hours significantly decreases the cerebral phosphocreatine to inorganic phosphate ratio (PCr/Pi) by approximately 4.7% in young healthy adults, indicating increased cellular energy consumption in the brain during extended wakefulness.
Source Excerpt
“Decrease in PCr/Pi revealed regional at all timepoints (0 p.m., 2 a.m., 4 a.m.) and in the averaged middle grid (−4.7±1.0%, p43<0.00005, t43=−4.53) when pooled at all 3 time points (Table S3, Fig. 4).”
Evidence from Studies
Supporting Studies
Single dose creatine improves cognitive performance and induces changes in cerebral high energy phosphates during sleep deprivation
The study measured brain metabolites using 31P-MRS and found a statistically significant decrease in the PCr/Pi ratio after 21 hours of sleep deprivation compared to baseline, indicating increased energy demand in the brain.