digraph brain {
node [fontname="Liberation Sans,sans-serif",gradientangle=90,style="filled",shape=box];
edge [penwidth=2];

subgraph basal_ganglia { 
// GABAergic pathways
{ edge [color=blue];
  striatum -> snpr; 
  snpr -> thalamus; 
  striatum -> gpe; 
  striatum -> gpi; 
  gpe -> stn; 
  gpi -> thalamus; }
// Dopaminergic pathways
  snpc -> striatum [color="magenta"];
//Glutamatergic pathways
{ edge [color=red];
  cortex -> striatum;
  stn -> gpi; 
  stn -> snpr; }
}

  thalamus -> cortex [color="red"];

  striatum [label="Striatum",fillcolor="cyan:white"]; 
  stn [label="STN",fillcolor="yellow:white"];
{rank=min; 
  cortex [label="Cortex"fillcolor="gray:white"]; }
{rank=same; 
  snpc [label="SNpc",fillcolor="red:white"]; 
  snpr [label="SNpr",fillcolor="red:white"]; }
{rank=same; 
  gpi [label="GPi",fillcolor="#32cd32:white"];
  gpe [label="GPe",fillcolor="#32cd32:white"]; }
{rank=max; 
  thalamus [label="Thalamus",fillcolor="gray:white"]; }
}