Schizophrenia: Symptoms, Brain Science, Medication and Treatment

"Doctor, he says people next door are spying on him. He says the television is sending him secret messages. We have no idea what to do." I hear versions of this opening almost every week. The family members sitting across from me look exhausted, worried, and silently afraid.

Schizophrenia affects roughly one percent of the global population^[1]. It typically emerges in late adolescence or early adulthood, and its impact on both the person living with it and their entire family can be profound and long lasting.

It is also among the most misunderstood psychiatric conditions. Schizophrenia is not "split personality." It is not a character flaw. It cannot be overcome through willpower alone. This article explains the neuroscience behind the illness, outlines the treatments that actually work, and answers the questions patients and families ask most often.

What schizophrenia is

Schizophrenia is a serious psychiatric disorder whose defining feature is a significant departure from how a person perceives and interprets reality. According to the DSM-5, a diagnosis requires that at least two of the following symptoms be present for a significant portion of one month, within a six-month illness period, and at least one must be among the first three^[2]:

• Delusions
• Hallucinations
• Disorganized speech
• Grossly disorganized or catatonic behaviour
• Negative symptoms

Clinicians typically group symptoms into two broad categories. Positive symptoms are things that are added: hearing voices that are not there, holding beliefs that are not grounded in reality. Negative symptoms are things that are taken away: flattened emotional expression, reduced motivation, social withdrawal. Many families first notice the negative symptoms: their loved one becomes a different person, spending entire days in their room, losing interest in everything.

What happens in the brain

Schizophrenia is not the result of "thinking too much." It is rooted in structural and neurochemical changes in the brain. Several key mechanisms have been identified^[3][4]:

Dopamine dysregulation

This is the most established neurochemical model of schizophrenia. The mesolimbic pathway shows excessive dopamine activity, driving positive symptoms such as hallucinations and delusions. At the same time, the mesocortical pathway shows reduced dopamine activity, contributing to negative symptoms and cognitive deficits^[3]. Every antipsychotic medication currently in use works, at its core, by blocking dopamine D2 receptors.

Glutamate system (NMDA receptor hypofunction)

Research has shown that blocking NMDA-type glutamate receptors with substances like PCP or ketamine can produce symptoms closely resembling schizophrenia in healthy individuals. This supports the idea that glutamate dysfunction is also part of the disease process and has opened the door to novel drug targets^[4].

Structural brain changes

Neuroimaging studies consistently show enlarged ventricles, reduced grey matter volume in the prefrontal and temporal cortices, and hippocampal atrophy in people with schizophrenia^[1]. These changes help explain the deficits in executive function, memory, and social judgement that characterise the illness.

Symptoms

Table 1. Positive vs. negative symptoms of schizophrenia

Negative symptoms tend to have a greater impact on daily functioning than positive symptoms. Positive symptoms generally respond well to medication, whereas negative symptoms remain one of the most difficult treatment challenges in clinical psychiatry.

Cognitive impairment is another core dimension. Deficits in attention, working memory, executive function, and processing speed often predate the onset of psychosis and are among the strongest predictors of whether a person can return to work and maintain social relationships.

Treatment

Medication: antipsychotics

Antipsychotic medication is the cornerstone of schizophrenia treatment. Modern practice relies primarily on second-generation (atypical) antipsychotics, which carry a more favourable side-effect profile compared with earlier agents^[5]. Commonly prescribed medications include:

Table 2. Commonly used antipsychotic medications

Clozapine deserves special mention. When a patient fails to respond adequately to two or more antipsychotic trials, the illness is classified as treatment-resistant schizophrenia. In this setting, clozapine is the only medication with clear evidence of superiority^[6]. Its use requires regular white blood cell monitoring due to the risk of agranulocytosis.

Long-acting injectable antipsychotics (LAIs) have become increasingly important in clinical practice. Paliperidone and aripiprazole are both available as monthly or quarterly injections, substantially reducing the risk of relapse caused by missed doses or deliberate discontinuation.

Psychosocial therapies

Medication controls symptoms, but returning to everyday life requires psychosocial support^[6]:

• Cognitive behavioural therapy for psychosis (CBTp): Helps patients evaluate the content of hallucinations and delusions, reducing associated distress^[7]
• Social skills training: Uses role-playing and structured exercises to rebuild interpersonal abilities
• Family psychoeducation: Teaches families about the illness and how to lower high expressed emotion, a well-established predictor of relapse
• Supported employment: Provides vocational coaching to help patients enter or return to the workforce

rTMS (repetitive transcranial magnetic stimulation)

The use of rTMS in schizophrenia is an emerging field, but there is already evidence worth noting. For medication-resistant auditory hallucinations, low-frequency rTMS targeted at the left temporoparietal junction (TPJ) has shown reductions in hallucination severity^[8]. For negative symptoms, high-frequency rTMS to the left dorsolateral prefrontal cortex (DLPFC) has also demonstrated positive effects^[9].

That said, rTMS is not yet part of the standard treatment algorithm for schizophrenia. It is best positioned as an adjunctive strategy for specific, treatment-resistant symptoms.

Assessment and diagnosis

Diagnosing schizophrenia requires a thorough clinical evaluation by a psychiatrist, including detailed history-taking, mental status examination, and the exclusion of other medical causes (thyroid disease, substance effects, brain lesions). Laboratory testing and brain imaging may also be needed.

There is no single self-assessment tool that can diagnose schizophrenia. If you or a family member is experiencing persistent hallucinations, delusions, marked behavioural changes, or a steep decline in social functioning, the right step is to schedule an evaluation with a psychiatrist as soon as possible. Research consistently shows that a longer duration of untreated psychosis (DUP) is associated with poorer long-term outcomes^[1].

When to seek help

• Persistently hearing voices or seeing things that others cannot
• Firmly held beliefs that are clearly not grounded in reality and resist correction
• Speech that is markedly disorganized and difficult for others to follow
• Sudden, marked social withdrawal, neglect of personal hygiene, and loss of daily routines
• Noticeable functional decline: inability to work, attend school, or manage basic tasks
• Any expression of intent to harm oneself or others

If someone is in acute crisis with safety concerns, call emergency services immediately. If the situation permits, book an outpatient psychiatry appointment for evaluation.

Frequently asked questions

Can schizophrenia be cured?

Schizophrenia is a chronic illness and, at present, cannot be cured. However, that does not mean the prognosis is necessarily poor. Studies show that 20 to 30 percent of patients achieve good functional recovery with long-term follow-up, and most patients can maintain a stable state with consistent treatment. The combination of early diagnosis, continuous medication, and psychosocial rehabilitation is the strongest predictor of a favourable outcome.

Is schizophrenia the same as split personality?

No. This is the most common misconception. The "split" in schizophrenia refers to the disconnection between thinking, emotion, and behaviour, not the presence of multiple identities. Multiple personality disorder, properly called dissociative identity disorder, is an entirely separate diagnosis.

The side effects are significant. Can I stop the medication?

Side effects are a legitimate concern. Common ones include weight gain, sedation, muscle stiffness, and metabolic syndrome. However, stopping medication abruptly carries a very high relapse risk; studies show that the relapse rate within one year of discontinuation can reach 80 percent. If side effects are intolerable, the correct approach is to discuss switching or dose adjustment with your psychiatrist, not to stop on your own.

A family member has schizophrenia. What should I do?

First, learn about the illness. Schizophrenia is not the patient's fault, nor is it caused by parenting. Second, encourage and accompany them to regular follow-up appointments. Third, reduce emotional tension at home by avoiding excessive criticism or overprotection. Finally, take care of yourself. Long-term caregivers of people with serious mental illness are at elevated risk of anxiety and depression. Support groups and individual counselling are valuable resources.

Dr. Tam's perspective

Schizophrenia is one of the most serious psychiatric conditions I encounter in my practice. I would like to say a few things directly to anyone reading this, whether you are living with the illness or caring for someone who is.

The diagnosis is serious, but it is not a death sentence. Our understanding and treatment of schizophrenia have improved enormously over the past two decades. Long-acting injectables have removed the daily burden of oral medication for many patients. Newer agents carry fewer side effects. Psychosocial rehabilitation programmes have enabled many patients to live independently and hold employment.

But the single most important factor remains this: do not interrupt treatment. In my clinical experience, nearly every acute relapse I see can be traced back to stopping medication. If the side effects feel unbearable, or if you feel well enough to try going without medication, please come and talk to me first. Dose adjustments, switching to a different agent, or adding a long-acting injectable are all options we can explore together. But stopping abruptly almost always leads to relapse.

References

1. Owen MJ, Sawa A, Mortensen PB. Schizophrenia. Lancet. 2016;388(10039):86-97. DOI · PubMed
2. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR). Washington, DC: American Psychiatric Publishing; 2022.
3. Howes OD, Kapur S. The dopamine hypothesis of schizophrenia: version III. Schizophr Bull. 2009;35(3):549-562. DOI · PubMed
4. van Os J, Kapur S. Schizophrenia. Lancet. 2009;374(9690):635-645. DOI · PubMed
5. Leucht S, Cipriani A, Spineli L, et al. Comparative efficacy and tolerability of 15 antipsychotic drugs in schizophrenia: a multiple-treatments meta-analysis. Lancet. 2013;382(9896):951-962. DOI
6. National Institute for Health and Care Excellence. Psychosis and schizophrenia in adults: prevention and management (CG178). NICE; 2014. NICE
7. Jauhar S, McKenna PJ, Radua J, et al. Cognitive-behavioural therapy for the symptoms of schizophrenia: systematic review and meta-analysis with examination of potential bias. Br J Psychiatry. 2014;204(1):20-29. PubMed
8. Slotema CW, Blom JD, van Lutterveld R, et al. Review of the efficacy of transcranial magnetic stimulation for auditory verbal hallucinations. Biol Psychiatry. 2014;76(2):101-110. DOI · PubMed
9. Aleman A, Enriquez-Geppert S, Knegtering H, Dlabac-de Lange JJ. Moderate effects of noninvasive brain stimulation of the frontal cortex for improving negative symptoms in schizophrenia: meta-analysis of controlled trials. Neurosci Biobehav Rev. 2018;89:111-118. PubMed