Figure 4. Imbalanced endogenous dopamine release during migraine attack and allodynia in vivo.

Left: Stable levels of endogenous dopamine during interictal phase (without headache). Center: Decreased endogenous dopamine release during spontaneous migraine headache attack (relative to interictal phase) on the striatum region (headache at rest). Right: Sudden increase in endogenous dopamine release during cutaneous allodynia relative to ongoing headache at rest (headache with sustained thermal pain threshold challenge [STPT]). BP = binding potential.