Major psychoses with mixed psychotic and mood symptoms: are mixed psychoses associated with different neurobiological markers?
OBJECTIVE
Evidence related to overlapping clinical and genetic risk factors in schizophrenia and bipolar disorder (BD) have raised concerns about the validity of 'Kraepelinian dichotomy'. As controversies mainly arise in mixed psychoses that occupy the intermediate zone between schizophrenia and BD, investigating neurobiological markers of mixed psychoses may be relevant to understanding the nature of psychotic disorders.


METHODS
In this article, we review studies comparing magnetic resonance imaging, neuropsychological and electrophysiological findings in mixed psychoses with each other, as well as with more prototypical cases of schizophrenia and BD.


RESULTS
The evidence reviewed suggests that mixed psychoses may be associated with different genetic and neurobiological markers compared with prototypical forms of schizophrenia and BD.


CONCLUSIONS
These findings may be compatible with more sophisticated versions of dimensional and continuum models or, alternatively, they may suggest that there is an intermediate third category between prototypical schizophrenia and BD.
Bora
E
E
Department of Psychiatry, Melbourne Neuropsychiatry Centre, and Melbourne Health, ORYGEN research Centre, The University of Melbourne, Melbourne, Vic, Australia. boremre@gmail.com
Yucel
M
M
Fornito
A
A
Berk
M
M
Pantelis
C
C
D015415:Biomarkers; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000235:genetics / Q000523:psychology*; D001921:Brain / Q000473:pathology; D004594:Electrophysiology / Q000379:methods; D020022:Genetic Predisposition to Disease; D006801:Humans; D008279:Magnetic Resonance Imaging; D009483:Neuropsychological Tests; D011618:Psychotic Disorders / Q000175:diagnosis* / Q000523:psychology*; D012307:Risk Factors; D012559:Schizophrenia / Q000175:diagnosis* / Q000235:genetics; D012565:Schizophrenic Psychology; D012720:Severity of Illness Index
D015415:Biomarkers