Central nervous system
Central nervous system

Temporal lobe seizure

Definition:
This type of seizure involves a temporary change in movement, sensation, or autonomic function caused by abnormal electrical activity in the temporal lobe on either one or both sides of the brain.

Alternative Names:
Epilepsy; TLE; Seizure - temporal lobe

Causes, incidence, and risk factors:

Temporal lobe seizures originate in the temporal lobe(s) of the brain. A seizure is an episode of abnormal electrical activity in the brain that can involve loss of consciousness or reduction of consciousness and/or involuntary movements and overwhelming sensations.

Temporal lobe seizures can affect people of any age, and can occur as a single episode or can be repeated as part of a chronic condition (See seizure disorder - epilepsy).

Transmission of information from nerve cell to nerve cell occurs by an electrochemical process. This process can be detected as electrical activity by an electroencephalograph (EEG).

Certain patterns of electrical activity can cause seizures, which are episodes when electrical signals spread in abnormal patterns within the brain. Given sufficient circumstances (such as exposure to certain drugs, high fever, or electrical stimulation), anyone can have a seizure.

Specific causes of temporal lobe seizures most commonly include localized areas of damage in the temporal lobe of the brain. This may result in scarring called mesial temporal sclerosis.

Causes can include traumatic injury, infection, damage to a portion of the temporal lobe due to lack of oxygen (ischemia or infarction), brain tumors, genetic syndromes, and discrete lesions of any sort.

As the temporal lobe is involved in processing emotion and sensations, seizures in this area may begin with feelings of fear, feelings of joy (sometimes with religious associations and the sensation of a "presence"), recall of certain music, or smells and other unusual symptoms.

Symptoms:
Aura (preliminary, warning symptoms):
  • Abnormal sensations
  • Epigastric sensations ("a funny feeling in my gut," "stomach rising," etc.)Hallucinations or illusions (vision, smells, tastes, or other sensory illusions)
  • Sensation of deja vu or recalled emotion/memory
  • Sudden, intense emotion not related to anything occurring at the time
  • Consciousness maintained during the seizure or spell (partial)
  • Consciousness reduced or lost during the seizure or spell (partial complex)
Motor/movement disturbances:
  • Rhythmic muscle contraction/relaxation (clonic activity) -- rare
    • Affecting one side of the body
    • Affecting one arm, leg, part of face, or other isolated area
Other focal motor (movement) symptoms:
  • Abnormal mouth behaviors
    • Lip smacking
    • Chewing or swallowing without cause
    • Profuse salivation "slobbering"
  • Abnormal head movements
    • Forced turning of the head
    • Forced turning of the eyes
    • Usually in the direction opposite of the location of the lesion
  • Abnormal movements
    • Repetitive movements, such as picking at clothing (automatism)
Focal sensory (sensation) symptoms:
  • Abnormal sensations
Autonomic symptoms: Other symptoms:
Signs and tests:
Diagnosis of temporal lobe seizure is suspected primarily on the basis of the symptoms presented and the results of testing. Diagnosis of the cause may include complete physical examination including detailed neuromuscular examination, which may or may not be normal.
  • An EEG (electroencephalograph, recording of brain electrical activity) shows characteristic changes confirming partial (focal) seizures and may show the focus (location of the cause).
  • A head CT scan or a cranial MRI may show the location and extent of the causative lesion.
  • A lumbar puncture may be necessary if there is suspicion of an infection causing the seizure.
Treatment:
The goals of treatment are to perform emergency measures, if necessary, and to reduce the incidence of future seizures.

Emergency treatment may not be required, unless the seizure becomes generalized or consciousness is lost. First-aid measures should be performed as appropriate, including protection from injury, prevention of aspiration of vomit or mucus into the lungs, and airway protection or assistance with breathing. Record details of the seizure and report them to the health care provider. Important details include date and time of the seizure, how long it lasted, which body parts were affected, type of movements or other symptoms, possible causes and other factors which provide information about the episode (such as what immediately preceded it).

The treatment of causes may stop the occurrence of seizures. This may include medical treatment of seizure disorders like epilepsy, surgical repair of tumors, or brain lesions and other treatments.


Oral anticonvulsants (antiseizure medications) are used to prevent or reduce the number of future seizures. Response is individual, and the medication and the dosage may have to be adjusted repeatedly.


Multiple, repeated seizures are usually treated with long-term use of an antiepileptic drug.

Follow-up includes reviewing the need for drugs at least yearly. Drugs may be required indefinitely. Plasma drug-level monitoring is important to continue control of seizures and reduce side effects.

Pregnancy, lack of sleep, skipping doses of medications, use of recreational drugs (including alcohol), or illness may cause seizures in a person with a previously well-controlled seizure disorder.

Use of informational jewelry or cards (such as Medic-Alert or similar) that indicate a seizure disorder may be advised to aid in obtaining prompt medical treatment if a seizure occurs.
Expectations (prognosis):
Seizures can occur as a single event or be recurrent. Seizures that recur with no precipitating factors are most commonly a chronic, lifelong condition termed epilepsy. (epilepsy).

Seizures that occur singly or in a discrete cluster are commonly caused by an acute condition, such as brain injury. They may occur secondary to an isolated incident, but can then develop into a chronic seizure disorder. Seizures within the first 2 weeks of a brain injury do not necessarily mean that a chronic seizure disorder will develop.

Serious injury can occur if seizure occurs while during driving or when operating dangerous equipment. Swimming and bathing without supervision are also not recommended. Contact sports are also not advisable. Therefore, these activities may be restricted for persons with poorly controlled seizure disorders.
Complications:
  • Progression to generalized seizures
  • Recurrent seizures (epilepsy)
  • Prolonged seizures, closely occurring seizures (status epilepticus)
  • Injury from falls, bumps, biting self, etc.
  • Injury from seizure occurring during driving or operating machinery
  • Aspiration of fluid, pneumonia
  • Permanent brain damage (stroke or other damage)
  • Side effects of medications (with or without observable symptoms)
Calling your health care provider:
Go to the emergency room or call the local emergency number (such as 911) if:
  • This is the first time the person has had a seizure or this is a new type or prolonged seizure.
  • This is an emergency situation.
  • If sequential seizures occur, or repeat seizure activity where consciousness is not regained in between (status epilepticus) is an emergency situation.
  • Any new symptoms occur, including possible side effects of medications, such as changes in mental status (drowsiness, restlessness, confusion, sedation, or others), nausea/vomiting, rash, loss of hair, tremors or abnormal movements, problems with coordination.
Prevention:
Treatment of causative lesions/disorders may reduce the incidence of seizure. In many cases, epilepsy is caused by a genetic disorder and may not be preventable.

Review Date: 7/28/2002
Reviewed By: Elaine T. Kiriakopoulos, M.D., MSc, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard University, Boston, MA. Review provided by VeriMed Healthcare Network.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2003 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.