Nav: Home

Connecting the dots in the migraine brain

January 13, 2020

London, UK: A neuroimaging study recently published in the journal Cephalalgia, the official journal of the International Headache Society, shared more evidence of structural changes in the brain of migraine patients. The study, entitled "Structural connectivity alterations in chronic and episodic migraine: A diffusion magnetic resonance imaging connectomics study", was conducted by a multidisciplinary team of neurologists and bioengineers, coordinated by Dr. Ángel Luis Guerrero, from the Headache Unit, Department of Neurology, University of Valladolid, Spain.

Migraine is one of the most disabling diseases in the world. To date, it is only diagnosed based on self-reported clinical symptoms, with no overt biomarker identified yet. As a neurological disorder, migraine is known to result from an aberrant central nervous system functioning. On the other hand, it may itself impact brain functioning with increased frequency of headache attacks (e.g., in chronic migraine patients).

Different research groups all around the world are attempting to uncover a brain signature of migraine patients, and nowadays brain connectivity is in the spotlight. Brain connectivity is obtained by neuroimaging techniques capable of mapping a full set of patterns of anatomical links in the brain and the strengths of these links (connectomes). The interpretation of these interactions follows the functional characteristics of each brain structure linked.

Dr. Guerrero's team assessed brain images from 160 volunteers; fifty healthy participants, 54 episodic migraine patients, and 56 chronic migraine patients. Migraine patients were assessed in the interictal period (headache-free days). Using a whole-brain tractography approach from diffusion magnetic resonance imaging (dMRI) and diffusion tensor imaging (DTI) techniques, a total of 620 connections between 84 cortical and subcortical gray matter regions were analyzed.

The researchers found structural brain connectivity changes between migraine patients and healthy volunteers, as well as between episodic and chronic migraine patients. Based on the number of streamlines from the anatomically-constrained tractography analysis and DTI descriptors, they found the following main patterns of structural changes:

Migraine Patients vs Controls

Simultaneous higher and lower number of streamlines in migraine patients, suggesting respectively coexistent strengthening and weakening structural connectivity changes in migraine. Strengthening connectivity was observed in many areas deeply implicated in migraine's pathophysiology, such as the caudate nucleus, thalamus and hippocampus, and other regions such as the insula, the superior frontal gyrus, and the precentral gyrus. The authors contextualized the role of the thalamus in the symptomatology of migraine such as photophobia, allodynia, and central sensitization processes, and the role of insula as the "hub of activity" in migraine. Strengthening connectivity in the hippocampus is akin to its role in pain processing and pain-related attention and anxiety.

For weakening connectivity patterns, the authors underscore the changes in the temporal lobe of migraine patients, which may represent a feature of interictal malfunctioning with other pain processing areas in these patients.

Episodic vs Chronic Migraine

Compared to episodic migraine patients, chronic migraine showed more streamlines, but decreased DTI descriptors (in axial and radial diffusivity), suggesting two different mechanisms connectivity alteration; more streamlines meaning potential adaptation to painful stimuli, and reduced diffusivity meaning possible axonal disturbance.

Moreover, in chronic migraine patients, DTI descriptors were positively correlated with the time from migraine onset, suggesting white matter plastic adaptation to highly recurrent painful stimuli. When adding the history of chronic migraine (the duration of chronic migraine) as a covariate in the statistical analyses, they found reduced streamlines of connections with the insula and thalamus, which was interpreted as indicative of temporal changes in pain processing areas throughout the course of migraine, resulting in plastic maladaptive changes.

According to Álvaro Planchuelo-Gómez, a bioengineer and the first author of the study, "This kind of study is very important to further investigate other aspects of the disease, such as identifying patterns of changes in patients who revert from the chronic to the episodic form of the disease, and treatment effects". Finally, another relevant aspect of this research is underscored by Dr. David García-Azorín, a neurologist and co-author of the study, "Migraine has no biomarker yet, therefore, more studies engaging the effort of a multidisciplinary team are needed to better understand the complexity of this disease, and, hopefully, establish a brain signature of migraine patients".
-end-
Contact Information: Dr. Ángel Luis Guerrero, Headache Unit, Department of Neurology, Hospital Clínico Universitario, Avenida Ramón y Cajal, 3, Valladolid 47005, Spain.
Email: gueneurol@gmail.com

About Cephalalgia and International Headache Society: Cephalalgia is the official journal published on behalf of the International Headache Society (IHS), which is the world's leading membership organization for those with a professional commitment to helping people affected by headache. The purpose of IHS is to advance headache science, education, and management, and promote headache awareness worldwide.

International Headache Society

Related Migraine Articles:

Acupuncture can reduce migraine headaches
Acupuncture can reduce migraine headaches compared to both sham (placebo) acupuncture and usual care, finds a new trial from China published by The BMJ today.
Migraine rats, medical facts
Migraine mechanisms are still far from being fully understood. Escalating data from animal models are 'fact-checking' the neurophysiological and behavioral correlates of the migraine experience in humans, and how they may be affected by current anti-migraine drugs or might translate into new therapies.
Connecting the dots in the migraine brain
This dMRI study pointed to the structural strengthening of connections involving subcortical regions associated with pain processing and weakening in connections involving cortical regions associated with hyperexcitability may coexist in migraine.
Predictors of chronic migraine
A review and meta-analysis found predictors of chronic migraine. Depression, high frequency attacks, medication overuse and allodynia increased the chances for new onset chronic migraine, while annual income -- US$ 50,000 showed a protective effect.
On nitroglycerin, cardiovascular homeostasis and...bam, migraine!
Researchers in Leiden, The Netherlands, found an exaggerated cardiovascular response to nitroglycerin infusion in migraine patients, suggesting an elevated systemic sensitivity to this compound in this population.
All roads lead to migraine
Dr. Samaira Younis, from the Danish Headache Center in Copenhagen, Denmark, shares her research results, which suggests there are no differences between migraine attacks clinical characteristics following administration of 2 different compounds in patients, CGRP and sildenafil, meaning they share common cellular signaling pathways.
Running away from exercise: The curious case of migraine
In spite of the widespread recommendation for regular physical activity as a strategy to manage migraine, for some patients, exercise can instead trigger migraine attacks.
Migraine prevention in children and adolescents
Two medicines already used to prevent migraine in adults also showed efficacy in adolescents with migraine.
Got a migraine? Relief may already be on your medicine shelf
According to a new report in The American Journal of Medicine, published by Elsevier, aspirin can be considered an effective and safe option to other, more expensive medications to treat acute migraines as well as prevent recurrent attacks.
Migraine headaches? Consider aspirin for treatment and prevention
Evidence from 13 randomized trials of the treatment of migraine in 4,222 patients and tens of thousands of patients in prevention of recurrent attacks supports the use of high dose aspirin from 900 to 1,300 milligrams to treat acute migraine as well as low dose daily aspirin from 81 to 325 milligrams to prevent recurrent attacks.
More Migraine News and Migraine Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Our Relationship With Water
We need water to live. But with rising seas and so many lacking clean water – water is in crisis and so are we. This hour, TED speakers explore ideas around restoring our relationship with water. Guests on the show include legal scholar Kelsey Leonard, artist LaToya Ruby Frazier, and community organizer Colette Pichon Battle.
Now Playing: Science for the People

#569 Facing Fear
What do you fear? I mean really fear? Well, ok, maybe right now that's tough. We're living in a new age and definition of fear. But what do we do about it? Eva Holland has faced her fears, including trauma and phobia. She lived to tell the tale and write a book: "Nerve: Adventures in the Science of Fear".
Now Playing: Radiolab

Uncounted
First things first: our very own Latif Nasser has an exciting new show on Netflix. He talks to Jad about the hidden forces of the world that connect us all. Then, with an eye on the upcoming election, we take a look back: at two pieces from More Perfect Season 3 about Constitutional amendments that determine who gets to vote. Former Radiolab producer Julia Longoria takes us to Washington, D.C. The capital is at the heart of our democracy, but it's not a state, and it wasn't until the 23rd Amendment that its people got the right to vote for president. But that still left DC without full representation in Congress; D.C. sends a "non-voting delegate" to the House. Julia profiles that delegate, Congresswoman Eleanor Holmes Norton, and her unique approach to fighting for power in a virtually powerless role. Second, Radiolab producer Sarah Qari looks at a current fight to lower the US voting age to 16 that harkens back to the fight for the 26th Amendment in the 1960s. Eighteen-year-olds at the time argued that if they were old enough to be drafted to fight in the War, they were old enough to have a voice in our democracy. But what about today, when even younger Americans are finding themselves at the center of national political debates? Does it mean we should lower the voting age even further? This episode was reported and produced by Julia Longoria and Sarah Qari. Check out Latif Nasser's new Netflix show Connected here. Support Radiolab today at Radiolab.org/donate.