Some people have a distinctive feeling or some other warning sign when a seizure is coming. A warning like this is also called an aura. Although some auras are unpleasant, they can be helpful because they can give you time to prepare for the seizure and keep yourself from being injured. Most injuries from seizures happen if there is no warning sign, if the warning is not recognized, or if there is not enough time to react to it.

Auras vary significantly between different people. Yours may happen right before a seizure or several minutes to hours earlier. Common warning signs right before seizures are changes in bodily sensations, changes in your ability to interact with things happening outside you, and changes in how familiar the outside world seems to you. Other warning signs that may happen hours before a seizure are depression, irritability, sleep disruption, nausea, and headache.

People with complex partial seizures are the most likely to experience warning signs. Approximately 55% to 65% of people with these seizures experience some type of aura. It is unclear whether having seizures that arise from one particular side of the brain makes you more likely to have auras than people whose seizures arise on the other side.

What have we learned about auras?

Researchers who have studied different types of auras for many years have found patterns. For many people, the sensations in an aura occur in the same order. For example, you may always feel fear, then déjà vu (the feeling that you've been there before), then a strange taste in your mouth. This pattern would point towards the existence of a prominent seizure pathway in your brain.

The part of your brain where your seizures originate (your seizure focus) also may be linked to a specific type of aura because an aura represents the beginning of a seizure. Since different parts of the brain are responsible for different things, the warning signs you experience will be related to the functions of the section of brain where the seizure is about to occur. People whose seizures begin in the temporal lobe tend to have certain types of auras and those whose seizures begin somewhere else often will have different types.

Does my aura mean I have an especially severe form of epilepsy?

Studies have shown that no specific aura is linked with a poor or negative outcome. Some researchers have found that fear during a seizure (ictal fear) is associated with increased psychological and behavioral disturbance, but the reasons for this are unclear.

What should I do if I have auras before my seizures?

Take advantage of the opportunity to look for a safe place to experience the seizure that is likely to follow. Telling other people about your warning signs will make it easier for them to help you and also can help them to understand epilepsy. You may be able to say, "I'm not feeling well" or "I'm going to have a seizure." Or you may just do something that other people or even animals, such as some dogs can recognize: You may suddenly get a strange expression on your face. You may stop talking in the middle of a sentence. If you are listening to someone else, you may seem to drift off and not pay attention. Your whole body may tense up. Family members and friends who recognize the meaning of these signs can help you stay safe during your seizure.

Should I tell my doctor about my auras, even if they are embarrassing or weird?

Absolutely. Auras aren't something you are able to control-they are caused by some small part of your brain that is misfiring. As strange as your aura may be, your doctor will be understanding.

It's important to tell your doctor about your auras so that your diagnosis will be more accurate and your treatment will be more focused. Knowing what type of auras you have can help your doctor find where your seizures begin. Although auras alone are rarely used to make a diagnosis, they can be used to confirm one.

Tell your doctor if you experience any warning signs on a regular basis, no matter how often they happen. If you experience a familiar sign that is not followed by any other seizure activity, make a note of it and tell your doctor about it anyway. You may be having small seizures, or another related condition that has been untreated. It's a good idea to keep track of your auras and seizures on a calendar so your report to the doctor will be accurate.

Topic Editor: Steven C. Schachter, M.D.
Last Reviewed:12/15/06