Schizophrenia--a disorder of the corollary discharge systems that integrate the motor systems of thought with the sensory systems of consciousness.
BACKGROUND
In spite of intensive research, no causal anatomical lesion has been found in schizophrenia. It may instead be caused by malfunctioning circuits in the corollary discharge, feed forward (CD-FF) systems of thought.


OBJECTIVE
To integrate with the CD-FF hypothesis recent data showing that subcortical motor systems participate in thinking.


METHODS
We review CD-FF concepts in relation to recent evidence that 'motor' brain structures participate in cognitive processing.


RESULTS
Malfunctioning of CD-FF systems that integrate thinking and consciousness could produce auditory hallucinations, delusions and disorganised thought.


CONCLUSIONS
We hypothesise that the pathophysiology of schizophrenia lies in integrative circuits of basal ganglia, thalamus and frontal cortex. Fruitful research directions would include elucidation of CD-FF circuits at even higher brain levels, the behaviour of these circuits during dreaming, and their responses to late maturational events including synaptic elimination.
Feinberg
I
I
Department of Psychiatry, University of California, Davis, CA, USA.
Guazzelli
M
M
D003072:Cognition Disorders / Q000523:psychology*; D003243:Consciousness; D006212:Hallucinations; D006801:Humans; D009434:Neural Pathways / Q000503:physiopathology; D011596:Psychomotor Disorders / Q000523:psychology*; D012565:Schizophrenic Psychology; D013850:Thinking