Definition and Overview
A migraine is not just a headache. Abnormalities in brain sensory processing and autonomic nervous system dysregulation It is a neurovascular disease that acts together. Nausea, vomiting, watery eyes that occur during a migraine attack, Symptoms such as stuffy nose and pale face It directly shows that the autonomic nervous system is involved.
Autonomic dysfunction is observed even in normal times without attacks. Migraine is a chronic autonomic dysregulation disorder. The possibility that it is just one phenotype is raised.
Autonomic reflex pathways in migraine
Why do autonomic symptoms occur during a migraine attack? This is because of the reflex pathway that connects the trigeminal nerve and the autonomic nerve.
The trigeminal nerve transmits pain signals to the face and head. When activated, these signals travel through the brainstem to Stimulates the autonomic nervous system control center. The stimulated autonomic nerve center passes through parasympathetic nerve fibers. It causes various autonomic responses around the head.
Symptoms that appear through this reflex pathway include: Redness of eyes, watery eyes, stuffy nose, runny nose, swollen eyelids, Sweat on the forehead and face, narrowing of the pupils, etc. Approximately 27-73% of migraine patients One or more autonomic symptoms were reported during the attack.
Sympathetic nervous system and migraines
Sympathetic dysfunction hypothesis
According to one hypothesis proposed in 2004, Migraine is a chronic dysfunction of the sympathetic nervous system and It's related. Abnormalities in sympathetic nerve function that occur in migraine patients include: It is not a temporary phenomenon but a continuous characteristic.
Factors that cause migraines (stress, sleep changes, Menstruation, etc.) have something in common: sympathetic nerve activity. This means that it causes rapid fluctuations. In platelets and immune cells of migraine patients There is a decrease in the number of adrenaline receptors Research results also support systemic sympathetic abnormalities.
Prodromal symptoms and sympathetic nervous system
A prodromal symptom that occurs before a migraine begins. Fatigue, yawning, changes in appetite, mood changes, There is neck stiffness, etc. These symptoms occur when the hypothalamus of the brain becomes activated. The hypothalamus contains the sympathetic and parasympathetic nerves. It is the upper center that regulates. Brain imaging studies also show that during the prodromal period, Hypothalamic activation was confirmed.
Parasympathetic nervous system and migraines
Decreased vagal nerve activity
Studies have confirmed reduced activity of the vagus nerve, the main parasympathetic nerve, in patients with migraine. On heart rate variability (HRV) testing, parasympathetic-related measures were significantly lower in patients with migraine than in healthy people.
In a study targeting pediatric migraine patients, A significant decrease in heart rate variability was confirmed. This is an abnormality in autonomic function. This suggests that it exists from the early stages of migraine.
Autonomic changes according to attack period
The autonomic function of migraine patients is It appears differently depending on the timing of the attack.
Before a attack, the sympathetic nervous system becomes dominant. During a attack, the parasympathetic nervous system is activated. At the same time, the sympathetic nervous system weakens. After a attack, autonomic function is generally suppressed.
Heart Rate Variability (HRV) and Migraine
Heart rate variability measures minute changes in heartbeat intervals. It is a test that objectively evaluates the functional state of the autonomic nervous system. It is widely used in migraine research.
Results of a study on heart rate variability in migraine patients In summary, it is as follows.
- Decreased overall autonomic control ability
- Decreased parasympathetic nerve activity
- Balance change due to sympathetic dominance
- Decreased vagal control of the heart
Chronic migraine patients compared to intermittent migraine patients Heart rate variability is also more severe. This is in the process of migraine becoming chronic. This means that autonomic dysfunction progresses together.
therapeutic significance
Understanding that the autonomic nervous system is involved in migraines Provides direct assistance in selecting treatment methods.
neuromodulation treatment
stellate ganglion block is performed on the sympathetic ganglion in the neck area. Excessive activity of the sympathetic nerves is prevented by injecting a local anesthetic. This is a procedure that suppresses and improves blood flow to the head area. In patients with migraine, the frequency of attacks decreased after treatment. It was reported.
Non-invasive vagus nerve stimulation is performed on the vagus nerve in the neck. Parasympathetic nerve activity is stimulated by applying external electrical stimulation. How to raise it. In both acute and preventive treatment of migraine The effect has been reported.
Autonomic nerve management through lifestyle habits
Aerobic exercise increases parasympathetic nerve activity and It is the most accessible way to improve heart rate variability. In a comprehensive analysis, regular aerobic exercise It was confirmed to significantly reduce migraine frequency. Breathing training, biofeedback, yoga, etc. By restoring balance of the autonomic nervous system It may help manage migraines.