EEG microstate co-specificity in schizophrenia and obsessive-compulsive disorder

Area of Science:

• Neuroscience
• Psychiatry
• Brain Imaging

Background:

• Research on electroencephalography (EEG) microstates suggests an imbalance in microstate C (increased) and D (decreased) temporal dynamics may be specific to schizophrenia.
• Similar microstate imbalances have recently been observed in obsessive-compulsive disorder (OCD).

Purpose of the Study:

• To investigate whether the pathological microstate pattern observed in schizophrenia is also co-specific to OCD.
• To compare microstate temporal dynamics between patients with OCD, schizophrenia, and healthy controls.

Main Methods:

• High-density EEG was used to analyze microstate temporal dynamics.
• Bayesian analyses, transition probabilities, and Source Imaging were employed for data analysis and source reconstruction.
• Participants included 24 OCD patients, 28 schizophrenia patients, and 27 healthy controls, all free of comorbid symptoms.

Main Results:

• Both OCD and schizophrenia patients exhibited increased microstate C contribution, decreased microstate D duration and contribution, and higher D→C transition probabilities compared to controls.
• Bayesian analyses indicated no significant differences in these microstate patterns between OCD and schizophrenia patients.
• Source reconstruction revealed similar dysregulations in the Salience Network (SN), Executive Control Network (ECN), and cortico-striato-thalamo-cortical (CSTC) loop in both patient groups.

Conclusions:

• The findings provide substantial evidence for a common etiological pathway in schizophrenia and OCD, characterized by microstate co-specificity.
• Shared anomalies in salience and external attention processing may underlie the co-expression of symptoms in both disorders.
• The study highlights potential shared neurobiological mechanisms contributing to the symptomatology of schizophrenia and OCD.