Therapeutic targets in major psychiatric disorders revisited

Excerpt

Following the hypothesis of schizophrenia being a disorder of impaired neural plasticity, numerous clinical trials have investigated the efficacy of non-invasive brain stimulation techniques in modulating plasticity and the treatment of this disorder. Hasan et al. [1] in this interesting invited review outline the four main stimulation protocols rTMS, UDP, PAS and tDCS which in some aspects have shown promising evidence to be an effective add-on treatment in schizophrenia. Alterations in GABAergic and glutamatergic neurotransmission may be improved by brain stimulation. However, since the optimal stimulation technique, target region and disease state for an intervention are still insufficient, the authors plead for funding further basic research in this area. Based on effects on sigma-1 receptors, which are involved in neuronal plasticity, synaptogenesis and myelination, add-on fluvoxamine treatment has been shown to improve negative symptoms in schizophrenia. In a meta-analysis, Kishi et al. [2] report that fluvoxamine treatment has significant effects on negative and overall symptoms in patients treated with first-generation antipsychotics, while no effects on positive symptoms and depression have been observed. In contrast, in patients medicated with second-generation antipsychotics only overall symptoms have been improved by add-on treatment. However, results should be regarded with caution since to date only a small number of studies have investigated this issue. …