What Causes Migraine Disease? 5 Factors in Migraine Neurobiology

Our understanding of the

disease

migraine

has changed, although there is still much to learn, let's review some of the most important principles about this medical condition. Migraine is a

disease

of the nervous system. In the past, we believed that

migraine

s were caused by changes in the blood vessels. in the brain it is now clear that

what

happens in the brain is much more complicated the underlying problem with migraine sufferers is that their nervous system is overly sensitive or overly nervous they react to small or normal stimuli with an exaggerated response those triggers can be the result of something we consume excess stress a lack of sleep or a change in the weather and how hypersensitive the nervous system is and

what

triggers the nervous system varies between people in other words, migraine disease is not a Not a single disease but a spectrum with symptoms ranging from mild and occasional to debilitating and daily.

Why does this genetics play a role in migraine disease? Let's remember how the nervous system works. If we look at what we consider a nerve, we see how it is made up of a set of similar neurons. Each individual neuron has a cell body with long extensions. When specialized sensors are stimulated, an electrical message is initiated on its way to the brain, but it is actually the flow of charged sodium ions into the cell through ion channels, followed by the passage of potassium through separate channels. ion channels outside the cell that generate the electrical signal, an electrical wave then moves rapidly towards the brain, at some point each neuron reaches its limit and the signal must be transferred to the next set of neurons, here the calcium channels open and They secondarily cause the release of chemicals called neurotransmitters at synapses, where receptors on adjacent neurons must detect the neurotransmitters and regenerate the electrical signal.

It is during this complex process that mistakes can be made. Think of a genetic defect as a confusing message about how the cell should make things. For example, one of the known genetic defects in migraine is one in which the cell is told to produce a protein that cannot fold into its normal three-dimensional shape when placed on the cell membrane and receives an electrical signal; The defective protein may open and let calcium ions enter the cell, but it may not be able to return to a fully closed position allowing a large amount of electrically charged calcium to enter the neuron.

In this case, the neuron would continue releasing neurotransmitters and the next cell would generate an exaggerated response. The consequence is that the neuron has overreacted to a stimulus. This is not just theoretical. Genetic defects of ion channels are known in families who suffer from migraine. Additionally, research has revealed genetic errors that affect the way neurotransmitters are released and inactivated, therefore each individual inherits a mixture of genetic errors, this may partly explain the wide spectrum of migraine symptoms and how, Between individuals, migraine can affect many different parts of the nervous system, not just the pain pathways, to illustrate this let's look at the trigeminal nerve, this nerve has branches that innervate the facial muscles.

The paranasal sinuses and teeth of the temporal mandibular joint, when stimulated, the branches of the trigeminal nerve transmit information back to the brain through the trigeminal nucleus in the brain stem, from here this message is sent to other parts of the conscious brain that recognize pain and the need to act, but for a person suffering from migraine, the threshold for initiating this distress signal is lower than normal and the amplitude of the warning is abnormally high, cortically spreading depression, so What

causes

the intense migraine headache? The current theory is that a trigger is set in the brain stem or in the periphery.

An abnormal electrical event called cortical propagated depression occurs. This is a wave of electrical activity that slowly travels across the surface of the crust. A spreading cortical depression first initiates flashing lights or abnormal smells, followed by a severe headache. Electrical depolarization produces a release of neurotransmitters and other molecules that cause secondary inflammation a person then experiences sensitivity to light nausea confused thinking and fatigue for hours by mechanisms that have yet to be defined the chemical reactions of an extended cortical depression appear to affect the dura mater where blood vessels dilate and contract, mast cells release their potent inflammatory chemicals, and trigeminal nerve fibers send signals to the brainstem, while spreading cortical depressions cannot explain many of the symptoms of migraine disease, it is likely. making it an important event in generating the brief, intense experiences most familiar to migraine sufferers.

Migraine has a chronic nature. Through central sensitization, migraine sufferers have been observed to have scarring in the brain. This may be a complication of repeated inflammation associated with widespread cortical depressions or other migraine events within the brain. Eventually, parts of the damaged nervous system simply cause frequent low-grade discomfort. symptoms such as increased sensitivity to touch or mild daily headaches tinnitus or decreased cognitive functions central sensitization partly explains why migraine sufferers have different symptoms at different stages of their lives and damage to blood vessels due to inflammation can explain the higher rates of stroke in migraine sufferers, and head trauma to the hypersensitive central nervous system may make migraine sufferers more vulnerable to chronic headache syndromes. migraine Another factor in migraine disease is that the abnormal electrical activity of one set of neurons can affect the behavior of adjacent ones.

The brain stem is the junction of many of our brain circuits. It is here that the information that controls many bodily functions is congregated in groups of cell bodies called nuclei. When electrical messages reach a nucleus, they can be redirected to other parts of the brain stem. The hypothalamus. The thalamus. cortex, these nerve centers have exotic names such as the trigeminal nucleus, pol Viner, dorsal raphe and locus karolius, while the trigeminal nucleus is the headache control center, these adjacent nuclei control stress, balance, mood mood, sleep and the autonomic system, an example is the generation of symptoms from the nasal and sinus region.

Many people confuse their chronic migraine symptoms with a recurrent infection; In fact, one form of chronic migraine disease is where the trigeminal nucleus generates signals that the brain interprets as abnormal pressure or pain from inside the sinuses, teeth, or eyes adjacent to the The trigeminal nucleus is the superior salivary nucleus. This nerve center controls the production of nasal secretions and the size of the turbinates inside the nose. A migraine sufferer not only feels pressure in the sinuses, but also experiences nasal congestion and a runny nose. The interaction between these nuclei can be affected. Another explanation for why some migraine sufferers have so many related symptoms, many of which do not involve pain.

Female hormones affect migraine disease. Sex hormones like estrogen and progesterone have a profound but poorly understood effect on our nervous system. Sex hormones affect the nervous system of all women. But for migraine sufferers, their rise and fall throughout life helps explain why migraine symptoms change so dramatically for women. Estradiol, better known as estrogen, has a complicated role in our nervous system; for example, for any neuron there are separate receptors in the nucleus as well as the surface of the cell and we know of the genetic defects of both receptors independently of the hormonal receptors we know that estrogen also sensitizes our body to pain while we still have a lot to learn about We know that sex hormones play a fundamental role in the ups and downs of migraine disorders.

The various biological mechanisms that describe how migraine disorders occur explain why there are different strategies to treat migraine disease and why no one approach works for everyone.