Temporal Lobe Epilepsy - Symptoms

Symptoms

The symptoms felt by the person, and the signs observable by others, during seizures which begin in the temporal lobe depend upon the specific regions of the temporal lobe and neighboring brain areas affected by the seizure. The International Classification of Epileptic Seizures published in 1981 by the International League Against Epilepsy (ILAE) recognizes three types of seizures which persons with TLE may experience.

1. Simple Partial Seizures (SPS) involve small areas of the temporal lobe such as the amygdala or the hippocampus. The term "simple" means that consciousness is not altered. In temporal lobe epilepsy SPS usually only cause sensations. These sensations may be mnestic such as déjà vu (a feeling of familiarity), jamais vu (a feeling of unfamiliarity), a specific single or set of memories, or amnesia. The sensations may be auditory such as a sound or tune, gustatory such as a taste, or olfactory such as a smell that is not physically present. Sensations can also be visual, involve feelings on the skin or in the internal organs. The latter feelings may seem to move over the body. Dysphoric or euphoric feelings, fear, anger, and other sensations can also occur during SPS. Often, it is hard for persons with SPS of TLE to describe the feeling. SPS are often called "auras" by lay persons who mistake them for a warning sign of a subsequent seizure. In fact, they are actual seizures in and of themselves. Persons experiencing only SPS may not recognize what they are or seek medical advice about them. SPS may or may not progress to the seizure types listed below.
2. Complex Partial Seizures (CPS) by definition are seizures which impair consciousness to some extent. This is to say that they alter the person's ability to interact with his or her environment. They usually begin with an SPS, but then the seizure spreads to a larger portion of the temporal lobe resulting in impaired consciousness. Signs may include motionless staring, automatic movements of the hands or mouth, altered ability to respond to others, unusual speech, or unusual behaviors.
3. Seizures which begin in the temporal lobe but then spread to the whole brain are known as Secondarily Generalized Tonic-Clonic Seizures (SGTCS). These begin with an SPS or CPS phase initially, but then the arms, trunk and legs stiffen (tonic) in either a flexed or extended position and then clonic jerking of the limbs often occurs. GTCS are often known in the vernacular as convulsions or "grand mal" (originally a French term) seizures.

Following each of these seizures, there is some period of recovery in which neurological function is altered. This is called the postictal state. The degree and length of the impairment directly correlates with the severity of the 3 seizure types listed above. SPS often last less than 60 seconds, CPS often last less than 2 minutes, and SGTCS usually last less than 3 minutes. The postictal state in the case of CPS and GTCS often lasts much longer than the seizure ictus itself. Because a major function of the temporal lobe is short-term memory, CPS and GTCS cause amnesia for the seizure. As a result, many persons with temporal lobe CPS and GTCS will not remember having had a seizure.

Local and national laws exist regarding the operation of vehicles, aircraft and vessels by patients with epilepsy. Most licensing departments do not allow driving of vehicles by persons with CPS or GTCS until they have been seizure-free for a specified period of time. The laws are complex and varied; affected persons must check with the appropriate licensing authority. In a few locations, health care providers are legally-required to report patients with epilepsy (and other medical conditions which cause episodes of altered consciousness) to their local department of motor vehicles.