 Originally Posted by Alyzarin
The original poster isn't going to respond; it seems he was only active for about a month after registering and hasn't signed on for nearly a year since.
Though I must say, if you what you say is accurate then that's quite annoying. Nearly every neurochemical research article ever made that studies schizophrenia doesn't differentiate between different subsets. In other words, combined with what you've said, it's all completely useless. (Not that I thought any differently as it was, since it's all fairly contradictory and inconclusive anyway.)
Yep I see. Oh well, at least some people might benefit from learning it's not so simple.
As for the research articles you seem to have read, well, the link I provided has a number of possible theories as to what might be causing Schizophrenia. I'll copy paste the section on Pathophysiology below:
 Originally Posted by eMedicine
Neuroimaging studies have demonstrated anatomical abnormalities, such as enlargement of the ventricles and decreased brain volume in medial temporal areas.[1] These findings are of greater research interest than clinical use.
The hippocampus is a small, cortical, supposedly seahorse-shaped part of the brain, curled within the medial border of the temporal lobe. The hippocampus is functionally part of the limbic system, where emotions are processed. The hippocampus is where we form declarative or episodic memories (memories of facts or events). The hippocampus is affected in Alzheimer disease, the preeminent disease of memory problems.
The hippocampus is also one of the many parts of the brain affected in schizophrenia. Disturbances in declarative memory are common in schizophrenia, although not as marked as in Alzheimer disease. Changes in the hippocampus, such as volume loss, change in perfusion, and change in contour, observed in brains from patients with schizophrenia (including nonmedicated patients) and relatives may be related to the cognitive problems of schizophrenia.[2]
Mattai et al studied a group of children with schizophrenia and their healthy siblings and controls.[3] The average age at the beginning of the study was 12 years. The hippocampal volume of the ill children was less than that of their siblings and controls and steadily decreased over 12 years of follow up, although not at an increasing rate. The children with schizophrenia were administered antipsychotic medications. The authors concluded that the hippocampal volume deficit was more likely due to the illness itself rather than the use of antipsychotic medication.
Interest has also focused on the various connections within the brain rather than localization in one part of the brain. Indeed, neuropsychological studies show impaired information processing in schizophrenia, and MRI studies show anatomic abnormalities in a network of neocortical and limbic regions and interconnecting white matter tracts.[4] A meta-analysis of studies using diffusion tensor imaging to examine white matter found that 2 networks of white matter tracts are reduced in schizophrenia.[5]
Other studies reveal less specific changes. In the Edinburgh High-Risk Study, researchers examined brain images of people at high genetic risk for schizophrenia. Seventeen of 146 people had reductions in whole brain volume and left and right prefrontal and temporal lobes. The changes in prefrontal lobes were associated with increasing psychotic symptoms.[6]
In a meta-analysis of 27 longitudinal structural MRI studies of patients with schizophrenia compared with controls, the authors found that schizophrenia was associated with loss of whole brain volume in both gray and white matter and an increase in ventricular volume over time.[7]
The first clearly effective antipsychotic drugs, chlorpromazine and reserpine, were structurally different from each other, but they shared antidopaminergic properties. Drugs that diminish the firing rates of mesolimbic dopamine D2 neurons are antipsychotic, and drugs that stimulate these neurons (eg, amphetamines) exacerbate psychotic symptoms. Therefore, abnormalities of the dopaminergic system are thought to exist in schizophrenia; however, little direct evidence supports this. This theory has recently undergone considerable refinement.
Hypodopaminergic activity in the mesocortical system, leading to negative symptoms, and hyperdopaminergic activity in the mesolimbic system, leading to positive symptoms, may coexist. (Negative and positive symptoms are defined below.) Moreover, the newer antipsychotic drugs block both dopamine D2 and 5-hydroxytryptamine (5-HT) receptors.
Clozapine, perhaps the most effective antipsychotic agent, is a particularly weak dopamine D2 antagonist. Undoubtedly, other neurotransmitter systems, such as norepinephrine, serotonin, and gamma-aminobutyric acid (GABA), are involved. Some research focuses on the N -methyl-D-aspartate (NMDA) subclass of glutamate receptors because NMDA antagonists, such as phencyclidine hydrochloride and ketamine, can lead to psychotic symptoms in healthy subjects.[8]
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