Altered processing of emotional stimuli in migraine: an event-related potential study.

BACKGROUND: Migraine patients report psychosocial stress to be among the major triggers for their migraine attacks. The mechanisms underlying the onset of migraine attacks are not yet fully understood. Neuroimaging studies have shown changes in the cortical excitability of migraine patients. Here, we investigated cortical activation related to processing of emotional stimuli in individuals with migraine.
METHOD: Twenty-four participants suffering from migraine attacks and 25 healthy volunteers had to passively observe pictures of emotional facial expressions (angry, happy and neutral). Electro-cortical activity was continuously recorded by means of an electroencephalogram (EEG), and ratings of valence (unpleasant vs. pleasant) and arousal (calm vs. exciting) were collected.
RESULTS: The migraine and control group did not differ in their ratings of valence and arousal of the visual stimuli. However, participants with migraine, in contrast to healthy controls, showed larger N170 amplitudes toward angry facial expressions compared to neutral ones. DISCUSSION: Individuals with migraine may have an altered cortical activity linked to the processing of emotional information. Thus, these individuals may process high arousing and threatening events preferentially, and this facilitated processing may be related to their already high cortical excitability.