Adjunctive Deep Transcranial Magnetic Stimulation (dTMS) for treatment of negative symptoms in schizophrenia A randomised sham controlled h-MRS study

Negativesymptoms are important when it comes to prognosis and outcomes ofschizophrenia. Both typical and atypical antipsychotics have shown limitedeffectiveness in modifying the psychopathology of negative symptoms.Hypo-activation of the ACC are found in neuroimaging studies of schizophrenia.It could be that an abnormal ACC in schizophrenia is unable to activate furtherin response to increasing task demands (Adams and David, 2007; Bersani et al., 2014). Manoach (2003) has described this relationshipin the dorsolateral prefrontal cortex (DLPFC) in schizophrenia, and relatestask-related DLPFC hypoactivity to decreased task performance. Considering thehypoactivity in these parts in schizophrenia, particularly with negativesymptoms, activation of these structure can lead to the improvement in innegative symptoms, as reported by Dlabac-de Langeet al in 2010, where they reported a significant superiority of active rTMS(DLPFC) over sham to reduce negative symptoms of schizophrenia (Dlabac-de Langeet al., 2010). Moreover, negative symptoms are related to specificneuroanatomical changes specially to mPFC and ACC. Compared to conventionalmethod of TMS, dTMS have an advantage of stimulating deeper structures. Resultsof studies using dTMS for the treatment of negative symptoms and cognitivedeficits have shown a positive therapeutic effect when used as an adjunct toantipsychotic agents. In a study seventy percent of patients who completedtreatment were responders, having achieved >20% improvement in negativesymptoms. (Levkovitz et al.,2011). To the best of our knowledge, there has beenno study assessing the effects of dTMS in negative symptoms of schizophrenia asmeasured by H-MRS findings of mPFC and ACC.