Can Neurological Disorders Cause Psychosis?

Psychosis can be a frightening word that many people don’t understand. But what does it really mean? In simple terms, psychosis describes a break from reality; when someone might see, hear, or believe things that aren’t real. It’s often linked to mental health conditions like schizophrenia, but it can also appear in people with neurological disorders that affect how the brain works.[1

If you’ve ever heard of someone having hallucinations or delusions and wondered whether it’s “just” a psychiatric issue or something happening inside the brain itself, the truth is, it can sometimes be both. In this blog, we’ll explore how and why neurological disorders can cause psychosis, what signs to look for, and what steps you can take if you or a loved one experiences these symptoms.

How Neurology and Psychosis Connect

What does “psychosis” actually mean? Psychosis involves hallucinations (seeing/hearing things not present) or delusions (strong beliefs not based in reality) and can significantly affect how someone perceives and interacts with the world.[2; 3]

While these symptoms often show up in psychiatric disorders, they are not exclusive to them.

Can Neurological Disorders Cause Psychosis?

Yes, neurological conditions can trigger psychosis, either directly through brain changes or indirectly through treatments, medications or complications. For example:

• Neurological diseases frequently present with psychiatric or neuropsychiatric symptoms (like mood changes, apathy, or hallucinations) alongside more obvious neurological signs. [4; 5]
• Secondary psychosis means a primary mental health disorder doesn’t cause your psychosis, but by a disease or injury that directly affects the brain.[6;7]
• Studies mapping brain lesions show that certain damage to brain circuits can lead to psychotic symptoms.[8]

Which Neurological Disorders are Known to Cause or Increase the Risk of Psychosis?

Several brain disorders can lead to psychotic symptoms or make them more likely:

• Parkinson’s disease: Besides movement problems, some people experience hallucinations or delusions, usually due to changes in the brain or the medications used to treat it [4]
• Dementia with Lewy bodies and other dementias: Hallucinations and delusions are common, appearing two to three times more often than in people without dementia [9]
• Brain injury or lesions: When parts of the brain are damaged or disconnected, it can sometimes lead to psychotic symptoms [8]
• Autoimmune or inflammatory brain disorders: Inflammation in the brain can sometimes cause psychosis as part of the illness itself [10]

What Causes Psychosis in Brain Disorders?

It often comes down to how the brain processes reality. When the brain’s “filtering system” or prediction pathways are disrupted, it can start misinterpreting what’s real and what isn’t, leading to hallucinations or unusual beliefs.[11]

Damage to the brain’s long-range communication networks, such as injury or degeneration, can also increase the risk by disrupting how different regions share information.[5]

On a chemical level, imbalances in neurotransmitters like dopamine and glutamate (whether from disease or medication) can further disturb normal brain signaling and trigger symptoms of psychosis.[3]

Delusions, Confusion, or Hallucinations: Signs to Watch for with Neurological Disorders

If you or someone you know has a neurological condition and starts showing signs like:

• Visual or auditory hallucinations (seeing things or hearing voices)
• Fixed beliefs about things that others don’t believe (delusions)
• Increased confusion, agitation, or a sudden change in thinking

Bring your symptoms to your neurology and/or psychiatry care team. Sometimes it is a treatable feature of the neurological disorder, or it is related to medication, and early recognition means faster intervention.

Why Does Showing Signs of Psychosis Matter for You as a Patient?

Because if you assume “it must be just psychiatric,” you might miss the fact that it could be tied to a neurological process that needs proper attention. On the flip side, if you assume “it’s a brain issue and nothing can be done,” that’s not entirely true either, because treatments exist, and identifying the cause helps guide correct therapy. A neurologist or neuropsychiatrist can help determine whether psychosis is secondary to a brain disorder (which changes how treatment is approached) versus a primary psychiatric illness.

Psychotic Break or Neurological Issue? Talk to Your Neurologist Right Away

Neurological disorders can cause psychosis, but the good news is that it can be treated once the cause is understood. If you or someone you love starts seeing or believing things that don’t seem real, it’s essential to talk with your neurologist or mental health provider. Early recognition helps your care team determine whether the symptoms are due to a brain condition, medication side effects, or something else.

With the right diagnosis and treatment, many people feel more stable and regain a sense of control.

Remember, psychosis isn’t “all in your head.” It may be a sign that something is happening in your brain, and getting help early can make all the difference.

Disclaimer: This blog is intended for educational and informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your physician, neurologist, or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment. Do not disregard professional medical advice or delay seeking it because of something you read on this blog.

Resources:

1. Psychosis. Cleveland Clinic [Internet]. Accessed November 12, 2025. Available from: https://my.clevelandclinic.org/health/symptoms/23012-psychosis
2. Backman, I. Psychosis Symptoms Emerge in Surprising Patterns, Researchers Find. Yale School of Medicine [Internet]. Published April 07, 2025. Accessed November 12, 2025. Available from: https://medicine.yale.edu/news-article/psychosis-symptoms-emerge-in-surprising-pattern-researchers-find/
3. Rawani NS, Chan AW, Dursun SM, Baker GB. The Underlying Neurobiological Mechanisms of Psychosis: Focus on Neurotransmission Dysregulation, Neuroinflammation, Oxidative Stress, and Mitochondrial Dysfunction. Antioxidants (Basel) [Internet]. 2024;13(6):709. Published 2024 Jun 12. doi:10.3390/antiox13060709 Accessed November 12, 2025. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC11200831/
4. Kim JS, Hong SB, Park KW, Lee ATC. Psychotic Symptoms in Patients With Major Neurological Diseases. J Clin Neurol [Internet]. 2024;20(2):153-165. doi:10.3988/jcn.2023.0501 Accessed November 12, 2025. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC10921039
5. Foucher JR, Luck D. Psychosis related to neurological conditions: pros and cons of the dis- / mis-connectivity models of schizophrenia. Dialogues in Clinical Neuroscience [Internet]. 8(1), 17–27. https://doi.org/10.31887/DCNS.2006.8.1/jfoucher Accessed November 12, 2025. Available from: https://www.tandfonline.com/doi/full/10.31887/DCNS.2006.8.1/jfoucher
6. Welch KA, Carson AJ. When psychiatric symptoms reflect medical conditions.Clinical Medicine [Internet]. 2018;18(1):80–87. https://doi.org/10.7861/clinmedicine.18-1-80 Accessed November 12, 2025. Available from: https://www.sciencedirect.com/science/article/pii/S1470211824012600
7. Arciniegas, D.B., Topkoff, J.L., Held, K. et al. Psychosis due to neurologic conditions. Curr Treat Options Neurol [Internet]. 3, 347–364 (2001). https://doi.org/10.1007/s11940-001-0039-0 Accessed November 12, 2025. Available from: https://link.springer.com/article/10.1007/s11940-001-0039-0
8. Pines AR, Frandsen SA, Drew W, et al. Mapping Lesions That Cause Psychosis to a Human Brain Circuit and Proposed Stimulation Target. JAMA Psychiatry [Internet]. Published Online: February 12, 2025. 2025;82;(4):368-378. doi:10.1001/jamapsychiatry.2024.4534 Accessed November 12, 2025. Available from: https://jamanetwork.com/journals/jamapsychiatry/article-abstract/2829812
9. Isaac E, Zhu CW, Rivera-Mindt M, et al. Psychosis in Neurocognitive Disorder Among Ethnoculturally Diverse Older Persons. Neurology Clinical Practice [Internet]. Published June 2025 issue. 15 (3) e200467 https://doi.org/10.1212/CPJ.0000000000200467 Accessed November 12, 2025. Available from: https://www.neurology.org/doi/10.1212/CPJ.0000000000200467
10. Crespi S, Stone R, Irving K. An inflamed brain can trigger psychosis. The search is on for patients who might be cured. AAAS Science Advisor [Internet] Published online May 16, 2024. doi:https://doi.org/10.1126/science.zet43su Accessed November 12, 2025. Available from: https://www.science.org/content/article/inflamed-brain-can-trigger-psychosis-search-patients-might-cured
11. Digitale E. Two key brain systems are central to psychosis, Stanford Medicine-led study finds. Stanford Medicine [Internet]. Published April 12, 2024. Accessed November 12, 2025. Available from: https://med.stanford.edu/news/all-news/2024/04/brain-systems-psychosis.html