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Published on: November 19, 2014

Brain electrical activity changes in treatment refractory schizophrenics after olanzapine treatment

Luis F Cerdán1, Miguel A Guevara, Araceli Sanz

  • 1Centro Comunitario de Salud Mental No. 1, Instituto Mexicano del Seguro Social, Mexico.

International Journal of Psychophysiology : Official Journal of the International Organization of Psychophysiology
|May 4, 2005
PubMed

Insights

Olanzapine (OLZ) effectively treats refractory schizophrenia by improving symptoms and synchronizing brain activity. EEG changes correlated with symptom improvement, indicating functional reorganization in responsive patients.

Area of Science:

  • Neuroscience
  • Psychiatry
  • Clinical Electrophysiology

Background:

  • Treatment-refractory schizophrenia (TRS) presents significant challenges in patient management.
  • Olanzapine (OLZ) is an atypical antipsychotic used for schizophrenia treatment.
  • Understanding OLZ's neurophysiological effects in TRS is crucial for optimizing therapy.

Purpose of the Study:

  • To investigate changes in brain electrical activity (EEG) induced by olanzapine (OLZ) in patients with treatment-refractory schizophrenia (TRS).
  • To correlate EEG alterations with clinical response to OLZ treatment.

Main Methods:

  • 14 paranoid TRS patients underwent EEG recordings before and after 8 weeks of OLZ treatment.
  • Psychopathology was assessed using the Brief Psychiatric Rating Scale (BPRS) and the Positive and Negative Syndrome Scale (PANSS).
  • Resting EEG data were analyzed for absolute power in different frequency bands and hemispheric correlations.

Main Results:

  • 57% of TRS patients showed a good response to OLZ, with significant reductions in PANSS positive and negative symptom scores.
  • EEG analysis revealed increased absolute power in theta1, theta2, and alpha1 bands, and decreased power in the beta2 band post-treatment.
  • Increased intrahemispheric correlations were observed in frontal areas and between frontal and posterior regions, alongside decreased interhemispheric correlation in the theta2 band.
  • EEG changes were more pronounced in patients with a better clinical response.

Conclusions:

  • Olanzapine (OLZ) demonstrates efficacy in improving psychiatric symptoms in treatment-refractory schizophrenia (TRS).
  • OLZ treatment leads to increased synchronization of brain activity within each hemisphere, suggesting functional reorganization.
  • The observed EEG changes correlate with clinical improvement, particularly in good responders, highlighting the potential of EEG as a biomarker for treatment response.

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