Abnormal functional connectivity in patients with post-traumatic headaches

A new study from Mayo Clinic researchers, published in The Journal of Headache and Pain, has examined the brain changes associated with acute post-traumatic headaches (PTH). These headaches can occur after a head injury or trauma and can be debilitating. The study involved 60 participants with acute PTH and 60 age-matched healthy controls. Using functional MRI (fMRI), the researchers found two key differences in the brains of PTH patients compared to healthy individuals.

Increased Iron Accumulation in Specific Brain Regions

First, the PTH patients showed higher levels of iron deposition in two brain areas: the left posterior cingulate and the bilateral cuneus regions. These areas are involved in various functions, including pain processing, attention, and visual processing. The accumulation of iron in these regions may disrupt normal brain function and contribute to the development and persistence of post-traumatic headaches.

Abnormal Functional Connectivity Patterns

Secondly, the researchers observed stronger functional connectivity between the bilateral cuneus (the visual processing area) and the right cerebellum (a region involved in motor control and coordination, and other functions) in PTH patients compared to healthy controls. Functional connectivity refers to the communication and synchronization between different brain regions. The abnormal connectivity patterns seen in PTH patients suggest disruptions in the brain networks responsible for processing sensory information, including pain signals.

Implications for Targeted Therapy

While these findings may have lacked utility in the past, they now have important implications for the treatment of post-traumatic headaches. We have been treating patients with repetitive transcranial magnetic stimulation (rTMS), a non-invasive technique that can modulate brain activity in specific regions. By stimulating the areas with abnormal connectivity, rTMS may help restore normal brain function and alleviate headache symptoms and other neurological and psychiatric symptoms. When possible, we perform fMRI scans on individual patients to identify the specific brain regions involved in their headache disorder. However, fMRI is still only a research tool, and when individual fMRI data is not available, studies like this one provide information on common brain changes associated with post-traumatic headaches that can be targeted with TMS.