Delayed, Reduced, and Redundant: Information Processing of Prediction Errors during Human Sleep.
The Journal of neuroscience : the official journal of the Society for Neuroscience March 18, 2026 Christine Blume, Marina Dauphin, Maria Niedernhuber et al.
During sleep, the human brain continues to process unexpected sounds, but the neural code becomes delayed, more redundant, and less rich as consciousness wanes. Twenty-nine participants heard an oddball sequence of tones while awake and during an 8-hour sleep opportunity. Prediction error responses occurred in all sleep stages (N1, N2, N3, REM). Mutual information analysis showed a substantial reduction in encoded prediction error information, especially during N3 and REM, even though electrical brain responses (ERPs) grew larger in deeper NREM sleep. Co-information analysis revealed that neural dynamics became increasingly redundant with deeper sleep. The neural code differed between wakefulness and sleep but was largely shared between N2 and N3 stages.