Our brain has a group of cells called the neurons that are the basic units of the brain involved in sending signals to the body for motor function and through the five senses, to receive signals and give back the appropriate response. Then the brain processes this information through conscious thought and unconsciously through nerve systems that control all the basic bodily functions, such as heart rate, temperature control and balance. In general, the all these functions can be proper if the blood supplies the required oxygen and nutrients to the entire region. Any blockage to these supplies can cause the basic units of the brain, the neurons to die.
The brain gets the supply of blood from the carotid arteries located in the front of the neck and the vertebral arteries that run in the back of neck through small canals in the bony spine of the neck. When any part of the brain loses its blood supply, it becomes oxygen deficient and can cause damage and the death of the brain cells. Additionally, the corresponding body functions also get hampered. This is called a stroke or a cerebro-vascular accident (CVA). However, in some cases the brain is able to regain its blood supply quickly, and the symptoms may resolve and this is known as a transient ischemic attack (TIA) (MedicineNet).
Transient ischemic attack is also called a brain attack. It is in general said that if a person has a TIA, the specific neurons in a specific region of the brain are dying. Since neurons typically do not undergo mitosis, when neurons ādieā they are not replaced with ānewā neurons so whatever physiological functions are controlled or regulated by those neurons (movement, speech, cognition) are greatly reduced or sometimes lost.
The symptoms of TIA disappear within an hour or in rare cases it may persist for up to 24 hours. Some of the most common symptoms include: numbness or weakness in the face, arm, or leg, especially on one side of the body; confusion or difficulty in speech or understanding speech; trouble seeing in one or both eyes; and difficulty with walking, dizziness, or loss of balance and coordination (National Institute of Neurological Disorders and Stroke).
TIA is also called a “warning stroke” or “mini-stroke” that produces stroke-like symptoms but with no lasting damage. However, it is important to recognize and treat TIAs as these can reduce the risk of a major stroke which can happen any time within a few months or a year.
The main difference between a stroke and TIA is that the blood flow stays blocked, and the brain has permanent damage in a stroke. It is found that blood clots can be the result of hardening of the arteries (atherosclerosis), heart attack, or abnormal heart rhythms and as a result the brain cells are affected within seconds of the blockage. Sometimes a TIA is caused by a sharp drop in blood pressure that reduces blood flow to the brain. This is called a “low-flow” TIA (American Heart Association).
In general, during a TIAs the blockages occur in the major arteries to the brain, such as the carotid arterie that are involved in supplying oxygenated blood to brain cells. These arteries are clogged with fatty deposits, called plaques that partially block the artery, and can lead to the formation of a blood clot. Further, this clot or the thrombus can completely block the artery, which slows or blocks blood flow to the area of brain fed by that artery. When the blood supply is blocked due to some of the above mentioned reasons, the brain cells die partially or completely based on the duration of loss of blood supply and result in further complications.
There are also cases when TIAs can be caused by blood clots that form in the heart and travel to the brain. And this is called emboli. Additionally, there are also cases when there is the closure of small blood vessels deep inside the brain (National Institute of Neurological Disorders and Stroke). In conclusion, it can be said that a person who experience TIA and its symptoms need to rush to the doctor and get treated. It can be a precursor of a major stroke that lead to damage of different parts of the body. Therefore, good treatment can prevent major damage.
Work Cited
American Heart Association Transient Ischemic Attack (TIA) [2008]. Web.
MedicineNet Transient Ischemic Attack (TIA, Mini-Stroke) [2008]. Web.
National Institute of Neurological Disorders and Stroke NINDS Transient Ischemic Attack Information Page [2008]. Web.