Fig. 7.

Schematic representation of the pathways involved in the SNR responses to prefrontal cortical stimulation.Broken and solid lines represent glutamatergic and GABAergic pathways, respectively.Bottom, Example of a complex response evoked in an SNR cell by stimulation of PL/MO areas of the prefrontal cortex. The early excitation is caused by the activation of the disynaptic cortico-STN–SNR pathway, the inhibition results from the activation of the direct NAcc–SNR pathway, and the late excitation involves the indirect NAcc–VP–STN–SNR pathway, which operates via disinhibition of the STN.