Resting-state EEG in schizophrenia: auditory verbal hallucinations are related to shortening of specific microstates.

OBJECTIVE

Abnormal perceptions and cognitions in schizophrenia might be related to abnormal resting states of the brain. Previous research found that a specific class (class D) of sub-second electroencephalography (EEG) microstates was shortened in schizophrenia. This shortening correlated with positive symptoms. We questioned if this reflected positive psychotic traits or present psychopathology.

METHODS

Resting-state EEGs of frequently hallucinating patients, indicating on- and offset of hallucinations by button press, were analyzed. Microstate class D duration was related to spontaneous within-subject fluctuations of auditory hallucinations.

RESULTS

Microstate D was significantly shorter in periods with hallucinations.

CONCLUSIONS

Microstates of class D resemble topographies associated with error monitoring. Its premature termination may facilitate the misattribution of self-generated inner speech to external sources during hallucinations.

SIGNIFICANCE: These results suggest that microstate D represents a biological state marker for hallucinatory experiences.