Decreased Alertness Reconfigures Cognitive Control Networks.

Area of Science:

• Cognitive neuroscience
• Neuroscience
• Psychology

Background:

• Cognitive control enables behavioral adaptation to changing situations.
• Alertness influences cognitive control, but daily fluctuations in wakefulness are understudied.
• Existing research often focuses on sleep deprivation rather than natural alertness variations.

Purpose of the Study:

• To investigate how natural daily fluctuations in alertness affect cognitive control.
• To examine neural and behavioral markers of conflict processing during decreasing alertness.
• To understand the resilience and compensatory mechanisms of cognitive control.

Main Methods:

• Combined an auditory conflict task (Simon task) with electroencephalography (EEG).
• Utilized a novel computational method to differentiate alert and drowsy trials.
• Analyzed behavioral responses and midfrontal theta-band power changes.

Main Results:

• Behavioral conflict effects and conflict adaptation persisted despite reduced alertness.
• Typical neural markers (local midfrontal theta power) diminished with decreased alertness.
• Increased long-range brain connectivity in the theta band was observed during drowsiness.

Conclusions:

• The cognitive control system demonstrates resilience to natural fluctuations in alertness.
• Neural mechanisms reconfigure, shifting from local to distributed processing, to compensate for diminished alertness.
• These findings highlight the brain's adaptive capacity during everyday variations in alertness.