---
title: What causes schizophrenia, mania, and depression? | Niyora
description: This is a theoretical proposal, not based on study of actual patients. The author suggests these conditions may result from imbalances in brain chemicals and
url: https://niyora.com/research/papers/integrated-theory-to-unify-status-among-schizophrenia-and-manic-depressive-2015/
---

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- What causes schizophrenia, mania, and depression?

Survey study, 2015

# What causes schizophrenia, mania, and depression?

This is a theoretical proposal, not based on study of actual patients. The author suggests these conditions may result from imbalances in brain chemicals and amino acids, influenced by activity levels.

 Early or limited evidence

None - theoretical paper

## What they did

This is a theoretical paper proposing a model to explain schizophrenia, mania, and depression. No study participants or experiments were conducted to test these ideas.

## What they found

The author proposes that mania may result from high physical activity combined with low serotonin production, depression from low physical activity combined with low serotonin, and psychotic symptoms from high serotonin and dopamine.

## What it means for you

This theory explains how chemical imbalances might develop, but it hasn't been tested in actual people. To know if these ideas are correct, researchers would need to study people with these conditions and test the theory.

## About the study

Original title Integrated theory to unify status among schizophrenia and manic depressive illness Authors Fukuda K Journal Medical hypotheses Year 2015 Study design Survey study What was tested None - theoretical model Read the paper [doi.org/10.1016/j.mehy.2015.06.012](https://doi.org/10.1016/j.mehy.2015.06.012)

## Topics

[Premenstrual syndrome (PMS)](https://niyora.com/research/topics/condition-pms/)[Low mood and depression](https://niyora.com/research/topics/symptom-depression-mood/)[Bipolar disorder](https://niyora.com/research/topics/comorbidity-bipolar/)[Schizophrenia and psychosis](https://niyora.com/research/topics/comorbidity-psychosis/)

Research tells you what helps on average. Niyora helps on the day it hits.

Calm down, see it another way, and decide what to say, with a PMS and PMDD app built by a doctor.

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