Figure 10.

Working models of two modes of information propagation through a basal ganglia-thalamo-pallial loop. A, The simplified classical view of disinhibition of thalamus where long pauses in the spontaneous inhibition by the GPi permit thalamic spiking. Spiking activity is represented with ticks on a flat line for the cortex, striatum [striatal spiny neuron (Striatal_SN)], pallidum, and thalamus. B, A modified view of thalamic disinhibition suggested by our data. Pallial HVC neurons that project to Area X (HVC_X) may drive phasic increases in pallidal projection neuron (Area X_PN) firing rates. This pallidal neuron bursting could be further shaped by striatal-mediated inhibition (Area X_SN), creating a deceleration feature that may drive thalamic neuron activity.