Daniel Mathalon

..Whether this abnormality precedes psychosis onset, emerges early in the illness, and/or progressively worsens with illness chronicity, is unknown...

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..If it reflects the action of the efference copy, it should be related to subsequent sensory suppression. If efference copy/corollary discharge mechanisms are abnormal in schizophrenia, it should be reduced in patients with schizophrenia...

..If so, schizophrenia patients should have reduced neural synchrony preceding movements, especially patients with severe hallucinations...

..Agency and expectancy had modest suppression effects on N1 and only in controls. Group differences in expectancy and agency could not account for failed corollary discharge during talking in patients...

..The results show at both cognitive and neural levels that disordered memory scanning contributes to deficient SIRP performance among schizophrenia patients...

..Collectively, the findings suggest that CB1R systems modulate top-down and bottom-up processing...

..The improbable occurrence of a standard should generate a P300, but only if the implicit local context generated by the recent stimulus history is processed...

..The successful action of the corollary discharge is seen when the response of the auditory cortex is suppressed during the Talk compared with the Listen condition. The protocol takes about 5 min to complete...

..We also asked whether people who have large P300s have higher power and greater synchrony of neural activity, and if the relationships between P300 and power and synchrony are different in patients and healthy controls...

..These papers illustrate approaches to translational neuroscience that will increase our understanding of schizophrenia and provide neurobiological endpoints for developing novel treatments...

..We present an alternative strategy with increased statistical power over a case-control study that uses brain imaging as a quantitative trait (QT) in the context of a GWAS in schizophrenia...

..We discuss the results in terms of pathophysiological mechanisms compromising event-related gamma phase synchrony in schizophrenia and further attempt to reconcile this finding with prior studies that failed to find this effect...

..Imprecision of the corollary discharge in schizophrenia may contribute to the misperception of inner experiences and thoughts as "voices" or auditory hallucinations...

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..CONCLUSIONS: Reduced fronto-temporal functional connectivity may contribute to the misattribution of inner thoughts to external voices in schizophrenia...

..Using N400, inferences can be drawn regarding the extent to which a given context primes a word...

..Patients with schizophrenia have deficits in auditory selective attention, but whether these attention deficits are evident at the earliest stages of auditory processing or emerge later in the processing stream is unknown...

..In AD patients, CRN amplitude was affected by item certainty (assessed a week earlier), being larger to items that were idiosyncratically difficult for patients to name...

..Additionally, differences between encoding and retrieval suggest that WM dysfunction may be manifested differently during the distinct phases of encoding, maintenance, and retrieval...

..Schizophrenia and alcoholism are characterized by brain volume abnormalities. Despite the frequent comorbidity of these conditions, the potentially compounded effects of comorbidity on brain structure have seldom been rigorously assessed...

..Implications for the cognitive significance of the P300 and its reduction in schizophrenia are discussed...

..Impaired self-monitoring is considered a critical deficit of schizophrenia. The authors asked whether this is a specific and isolable impairment or is part of a global disturbance of cognitive and attentional functions...

..Thus, error and conflict monitoring may be dissociable, subserved by both overlapping and distinct ACC regions...

..Schizophrenia is associated with deficits in using context to establish prepotent responses in complex paradigms and failures to inhibit prepotent responses once established...

..This is consistent with the operation of a precise forward model modulating the auditory cortical response to self-generated speech and allowing immediate distinction of self and externally generated auditory stimuli...

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..We tested the hypothesis that there would be a disruption of gamma-band coherence when the expected auditory consequence of speech does not match the auditory experience...

..Based on this, we argue that we can begin to use oscillations, across frequencies, to do translational studies to understand the neural basis of schizophrenia...

..Despite ERN/CRN abnormalities, post-error slowing and Pe were normal in patients, suggesting a dissociation of ERN and error awareness. Anterior cingulate and dorsolateral prefrontal cortical dysfunction in schizophrenia are implicated...

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