Background: Recent advances have highlighted the hypothesis of schizophrenia as a disorder causing defective connectivity among distinct cortical regions. Neurophysiological evidence supporting this hypothesis, however, is still lacking. Methods: In the present study, we used a novel twin-coil transcranial magnetic stimulation (tcTMS) approach to investigate ipsilateral parieto-motor connectivity in 20 schizophrenic patients (14 medicated, 6 unmedicated) and in 15 healthy age-matched volunteers. Results: In healthy subjects, a conditioning TMS pulse applied over the ipsilateral posterior parietal cortex (PPC) at 90% of resting motor threshold (RMT) intensity was able to increase the excitability of the hand area of the right primary motor cortex, with peaks at interstimulus intervals (ISIs) of 4 and 15 msec. This paradigm of stimulation failed to reveal any facilitatory parieto-motor interaction in medicated and unmedicated schizophrenic patients. The between-group difference in paired-pulse facilitation was not ISI-specific. In following analyses, we found that the effects across ISIs induced by PPC conditioning at 90% RMT correlated with the Global Assessment Functioning score and with the negative subscale of the Positive and Negative Syndrome Scale, showing that patients with a better global functioning and lower negative symptoms had less impaired connectivity. Moreover the same parameter correlated with illness duration. Conclusions: Parieto-motor connectivity is impaired in schizophrenia. Cortico-cortical disconnection might be a core feature of schizophrenia.
Koch, G., Ribolsi, M., Mori, F., Sacchetti, L., Codeca, C., Rubino, I.A., et al. (2008). Connectivity Between Posterior Parietal Cortex and Ipsilateral Motor Cortex Is Altered in Schizophrenia. BIOLOGICAL PSYCHIATRY, 64(9), 815-819.
|Tipologia:||Articolo su rivista|
|Citazione:||Koch, G., Ribolsi, M., Mori, F., Sacchetti, L., Codeca, C., Rubino, I.A., et al. (2008). Connectivity Between Posterior Parietal Cortex and Ipsilateral Motor Cortex Is Altered in Schizophrenia. BIOLOGICAL PSYCHIATRY, 64(9), 815-819.|
|Settore Scientifico Disciplinare:||Settore MED/25 - Psichiatria|
Settore MED/26 - Neurologia
|Revisione (peer review):||Sì, ma tipo non specificato|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1016/j.biopsych.2008.05.026|
|Stato di pubblicazione:||Pubblicato|
|Data di pubblicazione:||2008|
|Titolo:||Connectivity Between Posterior Parietal Cortex and Ipsilateral Motor Cortex Is Altered in Schizophrenia|
|Autori:||Koch, G; Ribolsi, M; Mori, F; Sacchetti, L; Codeca, C; Rubino, IA; Siracusano, A; Bernardi, G; Centonze, D|
|Appare nelle tipologie:||01 - Articolo su rivista|