Table 1.

Comparison of the imaging findings of the different studies examining the premonitory or lead-up to headache phase of the migraine attack.

Brain region	Stankewitz et al. (36) Task-evoked fMRI (trigemino-nociceptive stimulation)	Schulte et al. (37) Task-evoked fMRI (trigemino-nociceptive stimulation)	Schulte et al. (38) Task-evoked fMRI (trigemino-nociceptive stimulation)	Maniyar et al. (31) ${\text{H}}_2^{15}$O perfusion PET (observed triggered attacks)	Karsan et al. (35) Perfusion arterial spin-labeled MRI (observed triggered attacks)	Meylakh et al. (39) Resting-state fMRI (infraslow oscillatory activity, regional homogeneity, and connectivity)	Marciszewski et al. (40) Task-evoked brainstem responses (noxious orofacial stimulation) and resting-state fMRI connectivity	Marciszewski et al. (41) Diffusion tensor imaging (DTI) and fractional anisotropy (FA)	Karsan et al. (42) Resting-state BOLD-fMRI (observed triggered attacks)
Hypothalamus		+	+	+	+	+
Thalamus				+	+			+	+
Ventral tegmentum		+		+	+	+		+
Caudate				+	+
Putamen				+	+
Pallidum				+	+
Nucleus accumbens			+		+
Spinal trigeminal nucleus	+	+				+	+	+
Medulla								+	+
Dorsal pons		+	+	+		+		+	+
Frontal cortex				+	+				+
Precuneus/cuneus				+					+
Cerebellum				+
Anterior cingulate				+	+				+
Occipital cortex				+	+
Temporal cortex, including amygdala and hippocampus			+	+	+

The brain regions that have been suggested to be implicated in five or more studies have been highlighted in bold text.