Negative symptoms of schizophrenia—such as social withdrawal, lack of motivation, emotional flatness, and reduced speech—often persist even after the positive symptoms (hallucinations and delusions) have improved. These symptoms severely impact patients' social and occupational functioning, and unfortunately, they respond poorly to conventional antipsychotic medications. In this context, Repetitive Transcranial Magnetic Stimulation (rTMS) is gaining attention as a promising, non-invasive therapeutic option for treatment-resistant negative symptoms.
Repetitive Transcranial Magnetic Stimulation (rTMS) is a non-invasive neuromodulation therapy that uses magnetic pulses to stimulate specific areas of the brain. In the case of schizophrenia, high-frequency rTMS (typically 10 Hz) is targeted at the left dorsolateral prefrontal cortex (DLPFC)—a brain region linked to executive function, motivation, and emotional expression. Neuroimaging studies have consistently shown hypoactivity in this region among individuals with prominent negative symptoms.
The rationale for using high-frequency Repetitive Transcranial Magnetic Stimulation (rTMS) lies in its ability to increase cortical excitability and enhance dopamine release in the mesolimbic and mesostriatal circuits, which are implicated in anhedonia, avolition, and cognitive impairments commonly seen in schizophrenia.
Several randomized controlled trials and meta-analyses have shown that Repetitive Transcranial Magnetic Stimulation (rTMS) is effective in improving negative symptoms:
- A double-blind, placebo-controlled study involving 22 stabilized patients with schizophrenia demonstrated a significant 50% reduction in the Scale for the Assessment of Negative Symptoms (SANS) scores after 15 sessions of high-frequency (10 Hz) rTMS over the left DLPFC.
- In a separate 4-week trial, participants receiving 10 Hz rTMS showed marked improvement in negative symptoms compared to those receiving 1 Hz or sham stimulation. The benefits persisted at follow-up, indicating potential for long-term symptom relief.
- Functional imaging studies confirm that rTMS increases dopamine release in brain areas responsible for emotion and reward, reinforcing its role in treating negative symptoms.
The standard Repetitive Transcranial Magnetic Stimulation (rTMS) protocol for negative symptoms includes daily sessions for 3–4 weeks, using 10 Hz frequency at 110% of the motor threshold. Each session targets the left DLPFC, lasting about 20–30 minutes, and is delivered in an outpatient setting. Patients typically tolerate the therapy well, with only minor side effects like mild scalp discomfort or fatigue.
Repetitive Transcranial Magnetic Stimulation (rTMS) may be especially helpful for:
- Patients with treatment-resistant negative symptoms
- Individuals who have residual symptoms despite medication
- Those seeking non-pharmacological and brain-based interventions
- Patients experiencing reduced motivation, blunted affect, or impaired social functioning
Repetitive Transcranial Magnetic Stimulation (rTMS) represents an innovative and evidence-based solution for addressing the unmet need in treating negative symptoms of schizophrenia. By enhancing prefrontal cortex activity and promoting dopaminergic transmission, Repetitive Transcranial Magnetic Stimulation (rTMS) offers new hope for patients who have not responded adequately to antipsychotic therapy.