What Happens in the Body During a Migraine?

Migraines are severe headaches typically accompanied by nausea, vomiting, and sensitivity to light and sound. While the exact cause of migraines is unknown, they are thought to result from changes in brain activity, as well as genetic and environmental factors. During a migraine, several physiological changes occur in the body:

1. Vasoconstriction: The initial phase of a migraine is often characterized by the narrowing or constriction of blood vessels in the brain, leading to reduced blood flow. This can cause visual disturbances known as "aura," such as flashes of light, zigzag patterns, or blind spots.

2. Vasodilation: Following the vasoconstriction phase, the blood vessels in the brain rapidly expand or dilate, increasing blood flow. This dilation activates pain receptors in the meninges, the protective layers that surround the brain and spinal cord.

3. Neuroinflammation: Migraines are also associated with inflammation of the nervous system. Activated trigeminal nerve fibers release inflammatory substances, such as serotonin, histamine, and calcitonin gene-related peptide (CGRP), which further contribute to head pain and other migraine symptoms.

4. Cortical Spreading Depression (CSD): CSD is a wave-like electrical disturbance that propagates across the surface of the brain during a migraine. It involves the temporary disruption of normal neuronal activity and is thought to contribute to the spreading pain and neurological symptoms associated with migraines.

5. Trigeminal Nerve Activation: The trigeminal nerve, responsible for sensation in the face and head, plays a significant role in migraines. During an attack, the trigeminal nerve becomes overactive, leading to the release of neuropeptides that cause inflammation and pain in the head and face.

6. Autonomic Nervous System Involvement: Migraines can also affect the autonomic nervous system, which regulates involuntary bodily functions. This can result in symptoms such as nausea, vomiting, diarrhea, pale skin, sweating, and changes in heart rate and blood pressure.

It's important to note that the exact sequence and mechanisms involved in migraines can vary from person to person. Some individuals may experience all of these changes, while others may have only a few or even different symptoms. Understanding these physiological changes can help in developing effective treatments and management strategies for migraines.