Clozapine Augments Delta, Theta, and Right Frontal EEG Alpha Power in Schizophrenic Patients

Abstract

Objective. To explore the Quantitative EEG (QEEG) effects of established clozapine therapy regimes compared to those of previous ineffective antipsychotic regimes among 64 chronic (DSM-IV) schizophrenic patients. Methods. Data from 20 EEG channels referenced to linked ears were collected before and during maintenance clozapine therapy (mean duration 1.4 years). Absolute power was calculated in six frequency bands: delta (0.4–3.6 Hz), theta (4.2–7.8 Hz), alpha (8.2–11.8 Hz), beta1 (12.2–15.8 Hz), beta2 (16.2–19.8 Hz), and beta3 (20.2–23.8 Hz). Results. Clozapine augments power globally in the delta and theta bands, but this effect is more pronounced over frontal areas. Beta3 power was reduced. Alpha showed a frontal increase, more pronounced in the right, coupled with a posterior decrease with no net change in overall power. Conclusion. The demonstration of a significant clozapine-induced alpha topographic shift frontally and to the right is a novel discovery that may serve to encourage further investigations of subcortical structures in attempts to better understand the diverse aetiologies and optimal treatments of the schizophrenias.

Brain-imaging studies of treatment-resistant schizophrenia: a systematic review

“…These findings suggest that clozapine possibly affects attentive but not pre-attentive processing. Five studies used spectral analysis to assess effects of clozapine 65–69. Two early studies65,66 measured coherence and showed that resistant patients display interhemispheric and intrahemispheric dysconnectivity over anterior brain regions that clozapine partially normalised.…”

“…Three studies demonstrated the widespread effects of clozapine on spectral power, indicating both increases in fast wave and slow wave power. 67–69…”

Aberrant resting-state oscillatory brain activity in Parkinson's disease patients with visual hallucinations: An MEG source-space study

“…In addition, atypical antipsychotics (e.g. clozapine, quetiapine) are also used to treat psychosis in PD ( Wilby et al, 2017 ), and have been shown to increase power in lower frequencies and decrease power in higher frequencies ( Hyun et al, 2011 ; Maccrimmon et al, 2012 ). In our study, only two patients with multimodal hallucinations used atypical antipsychotics ( N = 1 clozapine, and N = 1 quetiapine).…”

Altered Causal Coupling Pathways within the Central-Autonomic-Network in Patients Suffering from Schizophrenia

“…The results of EEG frequency analyses demonstrated a decrease of central activation (power) in SZO in comparison to CON. It was proven [ 90 ], in general, that atypical antipsychotics like clozapine increase the central activation (power) in the δ and θ bands, especially in frontal brain regions, and thus, also directly affect, P EEG , The effects of placebo and antipsychotics (haloperidol, chlorpromazine, clozapine) were investigated by Small et al [ 91 ], who demonstrated that clozapine and chlorpromazine are associated with increased frontal δ central activity. In addition, the effect of antipsychotic treatment (clozapine) on clinical scores was demonstrated by significantly reduced positive and negative symptoms and global psychopathology [ 92 ].…”