Characterization of Corticobulbar Pharyngeal Neurophysiology in Dysphagic Patients With Parkinson's Disease  Emilia Michou, Shaheen Hamdy, Mary Harris, Adil Vania, Jeremy Dick, Mark Kellett, John Rothwell  Clinical Gastroenterology and Hepatology  Volume 12, Issue 12, Pages 2037-2045.e4 (December 2014) DOI: 10.1016/j.cgh.2014.03.020 Copyright © 2014 AGA Institute Terms and Conditions

Figure 1 Box plots of the mean PA scores of each group of PD patients. A significant increase in PA scores was noted in the SIon group with the administration of levodopa. The asterisks show the outlier - participant (P, participant). During the off medication stage, the group scores did not show deviations from the medians, and therefore no boxes were plotted for the off-medication phase. Clinical Gastroenterology and Hepatology 2014 12, 2037-2045.e4DOI: (10.1016/j.cgh.2014.03.020) Copyright © 2014 AGA Institute Terms and Conditions

Figure 2 Topographic maps of cortical representation of the pharynx in the 3 groups of patients (NSI, SIon, and SI) studied with single-pulse TMS when off and on levodopa. Marked increments on the axes represent distance along the coronal (right–left) and sagittal (anterior–posterior) axes (in centimeters) of the cortical grid. Off medication, there were no marked differences between groups. The NSI group of patients had minor reduction in cortical excitability of the stronger corticopharyngeal motor map with levodopa, and the group with unchanged swallowing impairments, irrespective of medication (SI, third row), had a bilateral increase in cortical excitability with medication. Additionally, the SIon group of patients showed increases of cortical excitability following the administration of medication. The vertex of each plot is marked by a “+.” The intensity scale shown on the right is color-coded as a percentage of the amplitude of the maximum response for each group. Clinical Gastroenterology and Hepatology 2014 12, 2037-2045.e4DOI: (10.1016/j.cgh.2014.03.020) Copyright © 2014 AGA Institute Terms and Conditions

Figure 3 Averaged group PMEP responses after stimulation of the right and left trigeminal cranial nerve pathway with TMS across the 3 groups both on and off medication. Note the increased pathway activation of the SIon group and the immediate decrease on the dopamine-replete state. The SI group did not show any change in the cranial pathway-evoked responses. *Significant differences: P < .05. Clinical Gastroenterology and Hepatology 2014 12, 2037-2045.e4DOI: (10.1016/j.cgh.2014.03.020) Copyright © 2014 AGA Institute Terms and Conditions

Supplementary Figure 1 Plot illustrating the CoG for each group both off and on levodopa. The NSI group is shown with squares (grey, off levodopa; black, on levodopa), the SIon group CoG is shown with circles (grey, off levodopa; black, on levodopa), and the CoG of the responses from the SI group is shown with triangles (grey, off levodopa; black, on levodopa). All measurements are in cm (± SD). Clinical Gastroenterology and Hepatology 2014 12, 2037-2045.e4DOI: (10.1016/j.cgh.2014.03.020) Copyright © 2014 AGA Institute Terms and Conditions