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7.6.1. Brain injuries

Brain diseases

The main brain diseases are:


The headache or headache is one of the most common diseases. They can have different causes, such as decreased oxygen delivery to the brain, damage to brain cells, inflammation of the brain or meninges, eye and nasal infections, stressanxiety, etc., although they can be classified into:

  • Primary headaches: Most headaches are not usually serious, although they can cause very severe pain.
    • Tension headache: it is the most frequent. Generates the feeling of tightness in the head.
    • Migraines or migraines: severe pain that affects only one side of the head, and may be accompanied by nausea and vomiting. It is produced by vasodilation of the blood vessels in the head.
  • Secondary headaches: Appears as a consequence of other diseases, such as sinusitismeningitis, a tumor, etc.

Most headaches do not require medical treatment, but if necessary, pain relievers will be used for tension headaches and vasoconstrictors for migraines.

Stroke or cerebral infarction

The stroke the most common disorder of the brain. It is usually associated with high blood pressure caused by sedentary lifestyle, smoking, consumption of fried foods, alcoholdrugs, or having other diseases, such as obesity or diabetes.

Neurological symptoms (weakness, paralysis, headache, difficulty speaking or seeing, alterations in sensitivity, etc.) can be transient, very intense, or even fatal (especially in brain hemorrhages).

There are two types of strokes:


Bleeding occurs when a blood vessel in the brain ruptures, causing blood to leak into the surrounding nerve tissue and damage it. It is usually caused by the rupture of an aneurysm, a pathological dilation that forms in the wall of a blood vessel at a point where the elasticity of the vessel wall is defective.

Aneurisma cerebral
By en:National Institutes of Health [Public domain], via Wikimedia Commons

Curiosity: Sharon Stone and Silvia Abascal.

Song: Ictus (cartoon).

Cerebral ischemia

The cerebral ischemia results from decreased blood flow to an area of the brain. The area of ​​dead or dying tissue is called an infarct.

The three main causes are:

  • The thrombosis. A plug forms, called a thrombus.

Vena en la que aparece un tómbolo taponándola y un émbolo desplazándose

By Blood_clot_diagram.png: en:User:Persian Poet Galderivative work: Aibdescalzo (Blood_clot_diagram.png) [CC-BY-SA-3.0, GFDL or GFDL], via Wikimedia Commons
Curiosity: Jorge Sanz.
  • The embolism. The blood moves the stopper, called plunger, from a larger glass, which is formed to a narrower vessel, where it is deposited.

Curiosity: Plácido Domingo.

  • ArteriosclerosisFat deposition causes the walls of blood vessels to thicken, thereby narrowing the channels.


By NHLBI [Public domain], via Wikimedia Commons

How to detect stroke symptoms

Video shared through social networks. If these symptoms appear, an ambulance must be called urgently to receive medical attention as soon as possible.

Closed head injury

They are brain injuries produced by impacts to the head that do not break the skull.

The bruises are closed traumatic brain trauma that produce a lesion in the cerebral circulatory system, resulting in a hematoma, with bleeding internal organs or tissues.

The contusions produced by these traumas occur when the brain is violently struck inside the skull. Contusions often occur on the opposite side of the brain where the blow occurs. The reason for these injuries, called kickbacks, is that the impact causes the brain to slam into the skull against the other side of the head.

The chronic traumatic encephalopathy, formerly called dementia pugilistica or "punch drunk syndrome" is a neurodegenerative disease caused by cumulative concussions and leading to dementia and general intellectual deterioration.

concussion is the immediate loss of consciousness accompanied by a short period of amnesia, which usually occurs after a head injury.

'There's an Injured Player Down on the Field' -- Shepherd (in blue) vs. Fairmont State at Ram Stadium Shepherdstown (WV) November 10, 2012
«There»s an Injured Player Down on the Field’ -- Shepherd (in blue) vs. Fairmont State at Ram 
Stadium Shepherdstown (WV) November 10, 2012 | Flickr: Intercambio de fotos. (s. f.).
Recuperado 6 de abril de 2013, a partir de

Brain infections

There are many organisms, such as virusesbacteriafungi, and other parasites that can cause infections in the brain and spinal cord. Some of the infections that can occur are:


The meningitis is an inflammation of the meninges, the membranes that surround and protect the brain and spinal cord. It can be caused by a virus or bacteria. It is a rare disease that can be serious because, if not treated quickly, the infection can affect the nervous tissue and cause irreparable damage, which can be fatal.


The encephalitis is an inflammation of the brain.


The myelitis is inflammation of the spinal cord.

Brain abscess

The brain abscess produced by the accumulation of pus as a result of infection, localized and associated with the destruction of the tissue.


The nervous system can also be affected by exposure to certain toxic substances that can enter the body through the digestive or respiratory tract or through the skin. For example, heavy metals can accumulate in the brain and affect it permanently, producing a toxic psychosis (chronic dementia produced by a neurotoxin).

Other times, some of the drugs used to treat neurological disorders have been found to have toxic effects, and patients may develop a motor disorder called tardive dyskinesia.

Some neurotoxins are endogenous (produced by the body itself), for example, the body can produce antibodies that attack components of the nervous system. The multiple sclerosis, for example, is a result of the attack by antibodies to the own myelin of the body.

Genetic factors

Sometimes, during cell division there can be problems, and the fertilized egg can end up having an abnormal chromosome or an abnormal number of normal chromosomes, as for example, people with Down syndrome, who on the 21 chromosome pair, in Instead of having two chromosomes, they have three.

Another example is Huntington's disease.

If you want more information, here is a link to the Down Spain website.


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