Fig. 4

Enhancement of the RTn firing rate later GABA B-Rs agonism in GP decreases the cortical beta frequency band. A Spectrograms of the RTn neuron and cortical activity under both experimental conditions (5-s bin). Activation of GABA B-Rs in the GP by baclofen (300 ng) injections reduced the spectral density of the cortical beta band and subsequently increased the RTn neuron spiking activity. Top: Raster plot showing the RTn neuron activity under basal conditions and after pharmacological stimulation. The bottom traces illustrate the cortical activity under both basal and baclofen conditions. The time scales apply to both traces. The plot was derived from the same neuron. B The graph shows the average power spectrum density under the experimental conditions. Stimulation of GABA B-Rs in the GP with 300 ng of baclofen decreased the spectral density at frequencies of 13 to 30 Hz. The inset plot shows the statistics of the effect of baclofen in the whole beta band. C Top: statistics of the effect of the application of baclofen to the ipsilateral GP in the low beta band (13–19 Hz; p = 0.000017; paired t test; n = 13 neurons). Bottom: Statistics of the response to intrapallidal baclofen in the high beta band (20–30 Hz; p = 0.007; paired t test; n = 13 neurons). D Heatmap showing the higher coherence between the MCx and RTn neurons in the beta frequency band. Coherence showed a significant increment relative to the basal values after baclofen administration (mean basal = 0.082 ± 0.006, mean after baclofen = 0.62 ± 0.06; p = 0.000007, paired t test; n = 13 neurons). The dashed lines indicate 95% confidence intervals. E Graph showing the coherence values after baclofen (300 ng) application between the MCx and RTn neurons at frequencies associated with low and high beta activity. At low beta activity (13–19 Hz), the coherence between RTn and MCx showed a significant increment (mean basal = 0.082 ± 0.006, mean baclofen = 0.62 ± 0.06; p = 0.000007, paired t test; n = 13 neurons). At high beta activity (20–30-Hz), coherence increased significantly relative to the basal values (basal = 0.07 ± 0.006, mean baclofen = 0.43 ± 0.03; p = 0.000002; paired t test; n = 13 neurons; E)