Overview

Schizophrenia is a significant serious mental illness that alters a person’s thoughts, feelings and behaviour.¹ This psychotic disorder is characterised by the presence of delusional beliefs, hallucinations, and disturbances in thought, perception, and behaviour. Historically the symptoms are classified into two types one is positive symptoms and the other one is negative symptoms. Positive symptoms are disorganised speech, hallucinations and delusions. Negative symptoms are anhedonia, poor speaking, and lack of motivation.² Schizophrenia patients require lifelong treatment. Early treatment may assist to reduce symptoms before major issues arise, improving the long-term outlook.³ The diagnosis of schizophrenia is obtained clinically after getting a complete psychiatric history and ruling out alternative causes of psychosis.¹ The diagnosis is associated with a 20% lower life expectancy, with suicide accounting for up to 40% of deaths.⁴

Transcranial magnetic stimulation

Transcranial magnetic stimulation (TMS) is a neurophysiological technique for noninvasively stimulating the nervous system. It involves applying a rapidly changing magnetic field to the cerebral cortex's superficial layers, which regionally creates tiny electric currents known as "Eddy or Foucault currents." The cerebral cortex serves as a secondary coil in this scenario. TMS has an advantage over electroconvulsive therapy (ECT) because it is targeted and avoids the resistance of the skull and superficial tissues.⁵ TMS uses electromagnetic induction to generate brief (~200-500 μs) yet powerful magnetic fields (>1.5 Tesla) that penetrate patients' undamaged skin and skull. TMS primarily affects cortical brain areas by producing peak absolute electric fields (~100 mV/mm). Repetitive Transcranial Magnetic Stimulation (rTMS) with a frequency of ≥1 Hz induces long-lasting changes in cortical excitability and plasticity, rendering it an effective tool for modulating complex brain function in both health and disease. Recent studies have shown that rTMS can induce long-lasting plasticity of excitatory and suppressive neural communication in animal models.⁶

Understanding of schizophrenia with symptoms and treatments

Schizophrenia is a severe psychological condition that leads people to look at reality incorrectly. They are unsure whether the images, sounds, and experiences they are having are real or imagined.⁷ There has been no single cause of schizophrenia revealed through research. Schizophrenia is thought to be caused by a combination of genetic and environmental causes. Psychosocial variables may influence the onset and progression of schizophrenia. Excessive use of cannabis is related with an increased risk of the condition.⁸ As with any illness, the intensity, period, and frequency of symptoms can vary; nevertheless, in people with schizophrenia, the incidence of severe psychotic symptoms often decreases as they age. Noncompliance with prescribed medications, the use of alcohol or illicit drugs, and stressful conditions all contribute to an increase in symptoms. Symptoms are divided into three major categories:⁹

• Positive symptoms include hallucinations, such as hearing voices or seeing non-existent objects, paranoia, and exaggerated or distorted perceptions, beliefs, and behaviours
• Negative symptoms are those that are abnormally missing. A loss or reduction in the ability to make plans, talk, express emotion, or seek joy
• Disorganised symptoms include confused and disorganised thoughts and words, difficulties with rational reasoning, and occasionally unusual behaviour or abnormal gestures

Hallucinations

When someone experiences a hallucination, whatever they see, hear, taste, smell, or feel things that are not real. The most typical type of hallucination is voice hearing. Even when those around them are unable to hear the voices or feel the feelings, the individual experiencing the hallucinations believes them to be extremely realistic. When individuals with schizophrenia hear voices, there are alterations in the speech centre of their brains, according to research utilising brain-scanning equipment. According to this research, hearing voices is a true experience as if the brain confuses thoughts for actual voices.⁹

Delusions 

In individuals with a diagnosis of schizophrenia, delusions tend to be mistaken beliefs that reflect faulty thought processes. You frequently won't realise that what you're experiencing isn't real if you have delusions. You may also be unable to react to reasoning that contradicts your misconception. Delusions fall into a few different categories;

• Slanderous illusions: The idea that someone is trying to harm you or that you are being assaulted or victimised in some other way is one of these delusions
• Extravagant illusions: These are also referred to as grandiose delusions and happen when you think you have extraordinary or unique abilities
• Hallucinations related to religion: They deal with a religious belief that doesn't fit within a broader cultural framework
• Physical illusions: These involve believing, in the absence of proof, that you suffer from a physical illness or that there is another issue with your body
• Delusions involving references: These suggest that you believe everyday occurrences are having a deeper significance for you
• Delusions of erotomania: These signify a conviction that someone is in love with you even in the absence of any supporting data¹⁰

Negative symptoms of schizophrenia

Negative symptoms can make it difficult for you to feel motivated, socialise, or control your emotions. Negative symptoms are typified by a lack of drive, interest, or both. They also tend to reduce expression. These symptoms may pose serious obstacles to your day-to-day functioning.

Primary and secondary qualities are present in negative symptoms. Primary symptoms are associated with the schizophrenia condition itself. Other factors, such as prescription side effects, stressors in the environment, and co-occurring mental health issues or substance use disorders, are linked to secondary symptoms. Schizophrenia's adverse symptoms can include;

• Avolition: an absence of drive
• Anhedonia: the incapacity to experience joy
• Asociality: Lacking curiosity in social relations
• Blunted affect: less emotional expression
• Alogia: a diminution of voice¹¹

Treatment

Even if symptoms have decreased, treatment for schizophrenia must last a lifetime. Medication and psychosocial therapy treatments can aid in the management of the illness. Hospitalisation might be required in some circumstances. The mainstay of treatment for schizophrenia is medicine, and the most often recommended drugs are antipsychotics. It is believed that they regulate symptoms by influencing the neurotransmitter dopamine in the brain. Managing signs and symptoms as successfully as possible at the lowest dose is the aim of antipsychotic drug therapy. In an effort to get the right outcome, the psychiatrist may experiment with various medications, dosages, or combinations. Aside from that, other prescriptions like anxiety or depression relievers, might be beneficial. Several weeks may pass before you observe symptom improvement.¹²

Transcranial magnetic stimulation for schizophrenia: Case studies

Twelve patients with schizophrenia participated in a double-blind crossover study done in 2000 by Hoffman et al. (2003). For 15 to 30 minutes, patients underwent 1Hz TMS over the left temporoparietal cortex at 80% of the motor threshold. The Positive and Negative Syndrome scale (PANSS) was used to measure the auditory hallucinations in all of these individuals while they were still taking antipsychotic drugs. Compared to sham therapy, active treatment was observed to significantly reduce the severity of hallucinations. It's interesting to observe that therapy effects were diminished in patients using anticonvulsant medication. This may suggest the necessity for an increased stimulus dose, as well as a decrease in or discontinuation of anticonvulsants. It was also an infra-motor threshold dose, which decreased the likelihood of a positive trial outcome.¹³

Hoffman et al. (2003) expanded on their findings with a double-blind crossover trial with 24 patients who continued to take their prescribed psychiatric drugs while receiving 1Hz TMS over the left temporo-parietal cortex for eight to 16 minutes per day at 90 percent motor threshold for seven days. Using the Hallucination Change Scale as the main measure, auditory hallucinations were evaluated differently from prior protocol. When TMS was administered in its active phase, 75% of the patients showed improvement, whereas just 17% did so during the sham phase. Patients also carried a counter to measure the frequency of hallucinations, which showed a linear decline over time in the active group. The duration of treatment effects was 15 weeks for over half of the trial participants.¹⁴

Safety of TMS

The safety and effectiveness of TMS in treating serious depression were examined in a multicenter study conducted in 2007. The trial included 301 people, and the only adverse event linked to TMS at a rate higher than placebo/sham was scalp discomfort, which affected 38.5% of subjects for one week at the beginning of the TMS treatment. There were no seizures.¹⁵

TMS for measuring excitatory and inhibitory processes in schizophrenia

Transcallosal inhibition appears to be disrupted in chronic schizophrenia patients compared to healthy controls, suggesting problems with functional connections in the brain. The callosal fibers' structural alterations could be the cause of this disturbance. Patients with and without medication for schizophrenia also appear to have a decreased facilitatory parietomotor link in the right hemisphere. Research suggests that these patients have abnormal neuronal activity propagation and voltage regulation in the motor cortex, which suggests defective cortical region connections. Increased interhemispheric functional connection between motor regions is also disrupted, pointing to a more widespread problem with neural connectivity. These results support the hypothesis that neuronal dysconnectivity, rather than impairments in particular brain regions, may be the cause of schizophrenia symptoms.

Moreover, research on motor cortical plasticity indicates deficits in long-term schizophrenia patients, pointing to problems with neural plasticity processes. However, evidence points to dynamic alterations brought on by higher demands for neural connections rather than baseline variations in motor cortex excitability as the source of these dysfunctions. Promising recent therapies focusing on brain plasticity and connection may help reduce cognitive symptoms associated with schizophrenia. The modulation of plasticity by neurotransmitters such as acetylcholine, dopamine, GABA, and NMDA receptors suggests possible therapeutic routes for the management of schizophrenia.¹⁶

Summary

In conclusion, because of its complicated symptomatology and ongoing care needs, schizophrenia poses a serious challenge to both afflicted individuals and mental health professionals. While psychosocial therapies and medicine are the mainstays of traditional treatment, newer methods like transcranial magnetic stimulation (TMS) have encouraging prospects for enhancing patients' quality of life and symptom control. The disturbed neuronal connections and plasticity mechanisms in the brains of people with schizophrenia have been clarified by recent research. Chronic schizophrenia patients appear to have impaired motor cortical plasticity, facilitatory parietomotor connections, and transcallosal inhibition, suggesting more general problems with functional neural connections than localised brain impairments. These results support the theory that schizophrenia is a brain dysconnectivity disorder rather than a result of particular local anomalies.

Additionally, studies examining TMS's safety and effectiveness as a therapeutic intervention for schizophrenia have produced encouraging findings. Studies on individuals receiving TMS treatment have shown improvements in symptom severity and decreases in auditory hallucinations, indicating TMS's potential as an additional therapy for the management of schizophrenia. In order to improve outcomes for people with schizophrenia, it will be essential to keep researching the underlying brain mechanisms of the illness and looking at cutting-edge therapy options like TMS. Future therapies may provide better symptom control and general functioning for persons with schizophrenia by focusing on brain connection and plasticity.