Limited areas of abnormal electrical disturbances in the brain lead to focal seizures. Symptoms will depend on the area affected by the abnormal electrical disturbance in the brain. These types of seizures can be characterized as simple or complex, each resulting in different outcomes.
Interruptions in normal brain activity can be caused by electrical disturbances. These disturbances occur as a result of neurons generating uncoordinated electrical signals. Normal and abnormal nerve cells within the brain can send abnormal electrical signals, resulting in seizures. Head trauma, such as stroke, can also lead to abnormal electrical activity and disturbances in the brain, leading to these seizures.
Electrical disturbances in the brain lead to a number of conditions. All seizures are caused by electrical disturbances in the brain, including focal seizures and seizures affecting the entire brain. Other conditions related to electrical disturbances include epilepsy and grand mal seizures.
Seizure disorders are a common neurological problem seen by physicians. These seizures can be a one-time occurrence or many can occur over a period of time. Those patients that continue to experience recurrent seizures are diagnosed as having epilepsy.
Symptoms associated with focal seizures vary based on the specific part of the brain the seizure impacted. This can include numbness of specific limbs or of part of the face, vision loss, and muscle contractions. Other signs of this type of seizure can include nausea, pain, and vomiting.
Simple focal seizures do not affect the patient's memory. Awareness is also not affected. The person who experiences seizures related to electrical disturbances will be fully aware of what is happening and will remember the incident.
Complex focal seizures also have electrical disturbances as the root cause. After experiencing a complex focal seizure, a patient may not have memory of the actual seizure or the symptoms related to the seizure. In addition, the patient may have difficulty remembering events before or immediately following the incident. This gap in memory is one factor that differs complex focal seizures from simple ones.
Secondary generalization may occur after this type of seizure. With secondary generalization, the electrical disturbances that caused the initial focal seizure continue. When this occurs, the electrical disturbances may affect the entire brain, resulting in a generalized seizure.
The treatment of focal seizures varies. Medication may be prescribed to prevent or limit future occurrences of focal seizures. In some cases, specifically for epileptic patients with limited success controlling seizures with medication, surgery may be an option.