A study found that patients with chronic migraine – both with and without medication overuse – have reduced susceptibility to the sound-induced flash illusion, suggesting migraine may be a disorder of multisensorial integration. Findings from this study were published in the Journal of Pain.
The study included 63 patients with chronic migraine from the University of Palermo headache clinic and 24 healthy controls. In the chronic migraine group, a total of 52 patients had Medication Overuse Headache (MOH). The mean attack frequency in the headache group was 14.9 attacks per month.
Participants were subjected to the sound-induced flash illusion, and both the chronic migraine group and healthy control group were compared based on the rate of fission illusion. The fission illusion was reported if a participant perceived multiple flashes on a computer screen that presented only 1 flash but was accompanied by multiple auditory beeps.
Compared to controls, participants with migraine demonstrated reduced fission phenomena (P <.0001). Additionally, patients with MOH with triptans (n=23) showed significantly less fission effects compared to other patients with chronic migraine (P =.008). Specifically, patients who overused triptans demonstrated significantly reduced fission phenomena compared to patients who overused analgesics (P =.003) but not from patients without MOH (P =.07). The researchers concluded that these findings support the idea that chronic migraine may contribute to the disruption of audio-visual interactions, resulting in a multisensory processing deficit.
Limitations of this study included the small sample size as well as the lack of direct comparisons between patients with chronic and episodic migraine.
Based on these findings, the study investigators concluded that the sound-induced flash illusion “appears a simple and reliable tool to reveal abnormal multisensory perception due to visual cortical hyper-responsiveness in migraine.”
Maccora S, Bolognini N, Cosentino G, et al. Multisensorial perception in chronic migraine and the role of medication overuse [published online January 3, 2020]. J Pain. doi: 10.1016/j.jpain.2019.12.005