Delayed early proprioceptive information processing in schizophrenia

It was first suggested that disordered proprioception was a core feature of schizophrenia by Sandor Rado in 1953. Using a recently designed proprioceptive event-related potential paradigm based on a change of load, we studied 12 unmedicated male out-patients with schizophrenia and 24 controls. In the patients, the early contralateral parietal activity was delayed and later central activity had increased amplitude, but gating was unaffected. The results could be understood within the deficiency of corollary discharge' model of schizophrenia but not within the 'filtering' theory. Further studies, including psychiatric controls, are necessary to verify the specificity of the abnormality. Declaration of interests Funding from the Lundbeck Foundation, the A. P. Moller and Chastine Mc-Kinney Moller Foundation, Butcher Max and Inger Worzner's Trust, Eli Lilly's Psychiatric Research Foundation, the Danish Research Council and the Danish Hospital Foundation for Medical Research, Region of Copenhagen, the Faroe Islands and Greenland.