What Is the Connection between Seizures and Brain Damage?

There are two main connections between seizures and brain damage. First, having seizures can cause brain damage. Second, having brain damage can put patients at risk for developing seizures. In some patients, whether the seizures came first or the brain damage came first is debatable, especially in the modern age as the technology available to image the brain and look for small abnormalities is more sophisticated, and there is increased ability to link seizure activity with underlying brain defects.

Seizures, which are unregulated discharges of electrical activity in the brain, can start in different patients for a variety of reasons. Regardless of the cause, however, a severe or prolonged seizure can decrease the blood flow to the brain, damaging it. Sometimes seizures are congenital, meaning that a person has a genetic predisposition towards developing a certain type of seizure. Other seizures develop from acquired conditions, such as abnormal concentrations of the minerals in the blood, overdoses of certain medications, and withdrawal from sedating substances, such as alcohol.

In many cases, patients with epilepsy, a condition marked by recurrent seizures, are born with certain brain abnormalities that cause their epilepsy. The connection between seizures and brain damage in this case suggests that the brain damage came first, leading to the recurrent seizures. Examples of structural brain lesions can include vascular malformations, abnormal development of the cerebral cortex, and having brain tissue located in incorrect locations inside the central nervous system.

Other patients who acquire brain damage can also develop seizures. Many times this damage could be the result of trauma, infection, or a tumor that has grown inside the cranial vault. In order to prevent a connection between seizures and brain damage, these patients are often given prophylactic anti-epileptic medications in order to keep them from developing seizures. The length of time they need to take these medications often varies on a case-by-case basis depending on the severity of their underlying brain damage.

Another connection between seizures and brain damage is that both conditions can be understood better with the help of a procedure called electroencephalography (EEG). In this procedure, a number of electrodes are placed on various locations on the subject's head, and brain activity is monitored over time. Performing an EEG provides a definitive diagnosis of seizures, as the synchronized electrical discharges that characterize them can be detected with this device. The presence of brain damage can also be identified with an EEG, since patients with abnormalities in their brain function have localized decreases in the brain's electrical activity in the damaged region.