Fig. 5. Change in STN firing rate does not suppress abnormal β-synchronization.

a Juxtacellular stimulation protocol used to increase the firing rate of single STN neuron as revealed by neurobiotin labeling on sagittal STN epifluorescence image (left image: arrow indicate cell body labeled, scale: 200 µm; right image: neurobiotin-labeled STN neuron, scale 20 µm). b Example of STN neuron firing increase during juxtacellular stimulation (scales bars are β-filtered ECoG: 50 µV, spike: 2 mV, time: 750 ms). c Population PSTH of all juxtacellularly excited STN neurons recorded during β-oscillations epochs (bin: 5 ms). d Comparison of the modulatory index (MI) distribution obtained from juxtacellularly excited STN neurons as compared with disinhibited STN neurons from eArch3-GP opto-inhibition. e Mean phase histograms of the juxtacellularly excited STN neurons during β-oscillation during OFF versus ON-juxtacellular stimulation epochs. f Schematic illustration of the electrophysiological recordings in STN expressing ChR2-EYFP in 6-OHDA rats. g Sagittal epifluorescence images illustrating the ChR2-EYFP signal at the level of STN (top left) and axon terminals in SNr (bottom left) and GP (right). Scale bar represent 200 µm. h Example of STN opto-excitation during laser stimulation (right, scales bars are: 0.5 mV, 1 s) and labeled with neurobiotin (left, scale bar is 20 µm). i Comparison of population PSTH between all ChR2-excited STN neurons and all STN neurons during eArch3-GP opto-inhibition (bin: 50 ms). j Distribution of the MI obtained from ChR2-excited STN neurons and disinhibited STN neurons during eArch3-GP inhibition. k Mean normalized power spectrum of mCx ECoG during OFF and ON laser epochs (analysis on the best β epochs for each rat). l Mean phase histograms of the STN neurons during OFF and ON laser epochs. Group data represents mean ± SEM, box-and-whisker plots indicate median, first and third quartile, min and max values. See also Supplementary Table 5 for statistical information.