Critical Roles of the Direct GABAergic Pallido-cortical Pathway in Controlling Absence Seizures
Fig 5
Effects of indirect GPe-related pathways on regulating absence seizures.
A, B: Two-dimensional state analysis (A) and frequency analysis (B) in the combined (−vcp2, −vζp2) and (−vcp2, −vζe) parameter spaces. Two considered indirect GPe-related pathways are: the inhibitory GPe-STN pathway (A1, B1) and the excitatory hyperdirect pathway from pyramidal neurons to STN (A2, B2). Three dynamical state regions are observed in the state analysis diagrams: the saturation region (I), the SWD oscillation region (II) and the low firing region (IV). In (A1) and (A2), the red dashed lines stand for the default coupling strengths of these two indirect GPe-related pathways, the white dashed lines represent the boundaries of suppression regions of SWDs, and the arrows denote the suppression directions of SWDs. In (B1) and (B2), the asterisk (“*”) regions surrounded by black dashed lines are the SWD oscillation regions falling into the 2–4 Hz frequency range. C: The TMFR as a function of −vcp2 for the inhibitory GPe-STN pathway (C1) and the excitatory hyperdirect pathway (C2). D: The RR as a function of −vcp2 for the inhibitory GPe-STN pathway (D1) and the excitatory hyperdirect pathway (D2). Compared to the results in Fig 4, these two indirect GPe-related pathways have relatively weak effects on controlling absence seizures.