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The Melbourne Psychiatric Brain Bank came into existence 25years ago. This review focusses on lines of research that have used tissue from the Brain Bank over periods of time. Hence there is a discussion on the significance of changes in levels of serotonin 2A receptors in the cortex of patients with schizophrenia and the relevance of such changes with regards to the pathophysiology of the disorder. The extensive contribution made by studies using tissue from the Melbourne Psychiatric Brain Bank to understanding the role of muscarinic receptors in the pathophysiology and treatment of schizophrenia is summarised. Finally, findings using brain bank tissue and "omics" technologies are reviewed. In each case, findings using tissue from the Melbourne Psychiatric Brain Bank is placed in context with research carried out on human postmortem CNS in schizophrenia and with findings in other lines of research that can help explain the causes or consequences of changes in CNS molecular cytoarchitecture. This timely review of data from the Melbourne Psychiatric Brain Bank reinforces the challenges faced in trying to increase our understanding of the molecular pathophysiology of schizophrenia. Continuing to increase our understanding of the disorder is important as a precursor to identifying new drug targets that can be exploited to improve the treatment of a disorder where treatment resistance remains a significant problem (Millan et al., 2016).

Traditionally, auditory hallucinations (AHs) heard outside the head have been regarded as more pathological than those heard inside, partly on the basis that internal AHs are conceptually closer to normal thinking than external AHs. Our data show that many patients hear AHs both internally and externally, and there were very few associations between location and demographic and clinical characteristics of the patients or with other characteristics of the AHs themselves. There was evidence that AHs heard internally were associated with better insight than those heard externally. Of those patients whose AHs included commands, greater proportions of those who heard them externally said they could resist than those who heard them internally or in both locations. There appears to be no consistent differential impact and effect of internal and external AHs, and there was no support for the historical view that internal AHs are more benign.

[(3)H]ketanserin binding to 5HT(2A) receptors was measured in the left planum temporale (sensory speech cortex) from schizophrenic and non-schizophrenic (control) subjects using both particulate membranes and tissue sections. There was a significant decrease in the affinity of [(3)H]ketanserin binding to particulate membranes from schizophrenic subjects who were treated with phenothiazines up to death. Adding 2nM chlorpromazine to brain tissue from control subjects caused a similar decrease in the affinity of [(3)H]ketanserin binding to particulate membranes. This suggests that the decrease in affinity observed in the phenothiazine-treated subjects was due to residual drugs. In addition, there was a significant decrease in the density of [(3)H]ketanserin binding in both particulate membranes and tissue sections from schizophrenic subjects which did not appear to be due to residual antipsychotic drugs. Analysis of the laminar distribution of 5HT(2A) receptors showed that this decrease was greatest in cortical layer III. The decrease in the density of 5HT(2A) receptors was significant whether schizophrenic subjects were receiving phenothiazines or haloperidol at the time of death, and there was no correlation between the last recorded dose of antipsychotic drug and 5HT(2A) receptor density. These data suggest that a decrease in the density of 5HT(2A) receptors in the planum temporale may be associated with the pathology of schizophrenia.

Dopamine (DA) D2 receptors which act by modulating second messenger pathways that include protein kinase C (PKC) and adenylate cyclase (AC) have been repeatedly shown to be increased in striatum from subjects with schizophrenia. Therefore it seemed possible that chronic up-regulation of DA-D2 receptors in the schizophrenic brain could result in a change in either of these two proteins. Hence we measured PKC and AC in striatum from 20 schizophrenic subjects and 20 non-schizophrenic subjects by quantitative autoradiography and could show no difference in the density of either PKC (436 +/- 35 vs. 485 +/- 29 fmol/mg tissue equivalents (TE), mean +/- SEM) or AC (77 +/- 9 vs. 80 +/- 7 fmol/mg TE) in the tissue from schizophrenic compared to the non-schizophrenic subjects. Thus, these data do not support the hypothesis that PKC or AC are changed in the schizophrenic brain.

This study was a preliminary open clinical trial aimed at exploring the hypothesis that estrogen may provide protection against schizophrenia in women. Eleven women with acute psychotic symptoms, as scored on the BPRS, SAPS and SANS, had 0.02 mg estradiol added to neuroleptic treatment for eight weeks. Their response was compared to seven women with similar symptom severity receiving neuroleptic treatment alone. Both groups had baseline hormonal assays of estrogen, progesterone, LH and FSH and underwent regular psychopathology ratings during the eight weeks. The group receiving the estradiol adjunct showed more rapid improvement in psychotic symptoms compared with the group receiving neuroleptics only. This difference was not sustained for the entirety of the trial. Both groups reached similar levels of recovery by the eighth week. These results suggest that estradiol may have antipsychotic properties and/or act as a catalyst for neuroleptic responsiveness in women with schizophrenia.

The Mental Health Research Institute Unusual Perceptions Schedule (MUPS) is a comprehensive instrument developed to record subjects' experiences of auditory hallucinations as completely as possible. The Schedule comprises a semi-structured interview and documents the physical characteristics of auditory hallucinations such as their onset and course, number, volume, tone, location, as well as other phenomena associated with them such as delusions. In addition, other aspects of hallucinations, such as coping strategies, contributing factors and subjects' personal views and reactions are also explored. In a sample of 100 subjects drawn primarily from the in-patient wards at Royal Park Hospital the MUPS was found to be an acceptable instrument to subjects in the field. Interrater reliability assessed in a subsample of 30 subjects was found to be high at the level of the individual items. Whether used in whole or part, the MUPS provides a reliable and acceptable method of assessing patients' experience of auditory hallucinations.

The validity of the simple dichotomy between positive and negative symptoms was examined by reanalysing the results of published studies using global ratings from Andreasen's SAPS and SANS. Global ratings from our own sample of 114 diagnostically heterogenous psychotic patients were also analysed. In none of the studies was a simple positive-negative dichotomy an adequate representation of symptom structure. The most commonly occurring structure consisted of three independent groups: Hallucinations/Delusions, Positive Thought Disorder and Negative Symptoms. These findings applied to both manic and schizophrenic groups of patients. An important implication of these results for future studies is that combining positive symptoms into a single scale is inappropriate because possibly differential relationships between Hallucinations/Delusions and Thought Disorder and a variety of external measures may be obscured by such a means of data reduction.

Recently, the validity of the simple dichotomy between positive and negative symptoms in psychosis has been questioned. A newly admitted group of 114 DSM-III patients with psychotic disorder were assessed using Andreason's positive and negative symptoms scales. Multidimensional scaling, augmented by cluster analysis, was applied to the full item set of these scales and showed clearly that there are three major, independent groups of symptoms: Hallucinations/Delusions, Positive Thought Disorder and Negative Symptoms. Within the Hallucinations/Delusions and Negative Symptoms groups there was some additional structure which does not conform to the SAPS and SANS sub-scales. In particular there was considerable heterogeneity within the Hallucinations/Delusions group, and delusions of persecution may represent a fourth independent dimension of psychopathology which is under-represented in these scales.

The recent explosion in knowledge in the neurosciences has heightened both the expectation of significant progress in understanding the underlying mechanisms involved in the psychoses as well as frustration over the failure of such progress to occur. As biological sophistication increases, it contrasts with the obsolescence of our nosological tools, which, through their influence upon research strategy, constitute a potential obstacle to progress. Currently dominant nosological paradigms are heavily based upon assumptions concerning the links between pathophysiology and symptoms, and between symptoms and the more distal consequences of disease. This review seeks to illustrate that the linkages between disease and its consequences are in fact much looser and more plastic than acknowledged by existing paradigms, which are constrained by tradition. Since faulty assumptions concerning these linkages are so fundamental to the current nosology, it is argued that major reform is necessary. While this can be justified on research grounds alone, there are also compelling clinical reasons why reform of this kind is important and overdue.

Deficits in emotional prosodic processing, the expression of emotions in voice, have been widely reported in patients with schizophrenia, not only in comprehending emotional prosody but also expressing it. Given that prosodic cues are important in memory for voice and speaker identity, Cutting has proposed that prosodic deficits may contribute to the misattribution that appears to occur in auditory hallucinations in psychosis. The present study compared hallucinating patients with schizophrenia, nonhallucinating patients and normal controls on an emotional prosodic processing task. It was hypothesised that hallucinators would demonstrate greater deficits in emotional prosodic processing than non-hallucinators and normal controls. Participants were 67 patients with a diagnosis of schizophrenia or schizoaffective disorder (hallucinating=38, non-hallucinating=29) and 31 normal controls. The prosodic processing task used in this study comprised a series of semantically neutral sentences expressed in happy, sad and neutral voices which were rated on a 7-point Likert scale from sad (�3) through neutral (0) to happy (+3). Significant deficits in the prosodic processing tasks were found in hallucinating patients compared to non-hallucinating patients and normal controls. No significant differences were observed between non-hallucinating patients and normal controls. In the present study, patients experiencing auditory hallucinations were not as successful in recognising and using prosodic cues as the nonhallucinating patients. These results are consistent with Cutting's hypothesis, that prosodic dysfunction may mediate the misattribution of auditory hallucinations. © 2006 Published by Elsevier B.V.

To investigate the association between competence to give informed consent to treatment, specific symptomology and diagnostic category, 110 inpatients diagnosed with DSM-IV acute schizophrenia ( n = 64), schizoaffective disorder ( n = 25) and bipolar affective disorder ( n = 21) were interviewed using the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) and the Positive and Negative Syndrome Scale (PANSS). Results indicated no significant difference in competence between the three disorders. Elevated positive, cognitive and excitement PANSS factor scores had lower MacCAT-T scores. Further analyses indicated symptoms that impair cognition; particularly, conceptual disorganisation and poor attention were most consistently related to poor performance on competence tests.

There is strong evidence that hippocampal 5-hydroxytryptamine (5-HT) systems are affected in schizophrenia and hence we have studied a number of markers of the 5-HT system in hippocampi from subjects with schizophrenia. Using in situ radioligand binding with autoradiography we measured [ 3 H]proplyamino-8-hydroxy-1,2,3,4-tetrahydronapthalene, [ 3 H]ketanserin and [ 3 H]sumatriptan binding in hippocampi from 20 schizophrenic and 20 control subjects. There were significant decreases in the density of [ 3 H]ketanserin binding to the 5-HT 2A receptor (5-HT 2A R) in the Cornu Ammonis (CA) 3 ( p =0.006), CA 1 (stratum radiatum p =0.02; pyramidal layer p =0.0008) and subiculum (pyramidal layer p =0.0004), as well as methiothepin-insensitive [ 3 H]sumatriptan binding to the 5-HT 1F R in the CA 1 ( p =0.016), stratum radiatum/lacunosum moleculare ( p =0.04) and subiculum ( p =0.015) from subjects with schizophrenia. There were no differences in the densities of 5-HT 1A R, 5-HT 1D R or 5-HT 4 R in hippocampi from subjects with schizophrenia. These data support the hypothesis that regionally specific reductions in the density of the 5-HT 2A R and 5-HT 1F R are a component of the pathological processes underlying schizophrenia.

Brain abnormalities have been identified in patients with schizophrenia, but what is unclear is whether these changes are progressive over the course of the disorder. In this longitudinal study, hippocampal and temporal lobe volumes were measured at two time points in 30 patients with first episode psychosis (mean follow-up interval=1.9 years, range 0.54-4.18 years) and 12 with chronic schizophrenia (mean follow-up interval=2.3 years, range 1.03-4.12 years) and compared to 26 comparison subjects (mean follow-up interval 2.2 years, range 0.86-4.18 years). Hippocampal, temporal lobe, whole-brain and intracranial volumes (ICV) were estimated from high-resolution magnetic resonance images. Only whole-brain volume showed significant loss over the follow-up interval in both patient groups. The rate of this volume loss was not different in the first episode group compared to the chronic group. There were no changes in either hippocampal or temporal lobe volumes. The negative findings for the hippocampus and temporal lobes may mean that the abnormalities in these regions are stable features of schizophrenia. Alternatively, the period before the onset of frank psychotic symptoms may be the point of greatest risk for progressive change.

Structural alterations in the brains of some schizophrenic patients suggest an impairment of brain development, possibly as a result of intrauterine compromise. In this study we have tested the hypothesis that placental insufficiency during the second half of pregnancy in the guinea pig results in structural alterations similar to those seen in some schizophrenic patients. Placental insufficiency was induced in pregnant guinea pigs via uterine artery ligation at midgestation. At 60 days gestation (term: 68 days gestation) the fetal brains were prepared for quantitative histological and immunohistochemical analysis and compared with controls. Placental insufficiency resulted in growth-restricted animals with significantly larger cerebral ventricles, reduced cross-sectional area of the cerebral cortex and the striatum and reduced hippocampal volume compared with controls. There were fewer neuronal nitric oxide synthase (nNOS)-positive cells in layers 5-6 of the cingulate cortex, and in layer 1 of the frontal and temporal cortices. In contrast, there were no significant alterations in the optical density of tyrosine hydroxylase (TH), a rate-limiting enzyme in the biosynthesis of catecholamines and the dopamine transporter (DAT) in the striatum in growth-restricted animals compared with controls. These findings indicate that developmental disturbances can produce anatomical changes that resemble those found in some individuals with schizophrenia.