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Temporal lobe epilepsy is a form of epilepsy, a chronic neurological condition characterized by recurrent seizures. Causes Temporal lobe epilepsies are a group of medical disorders in which humans and animals experience recurrent epileptic seizures arising from one or both temporal lobes of the brain. Two main types are internationally recognized. Because of strong interconnections, seizures beginning in either the medial or lateral areas often involve neighboring areas of the brain. The causes or etiology of different temporal lobe epilepsies vary. MTLE is often associated with generalized tonic-clonic (convulsive) seizures occurring in children under age 5 during fevers (febrile seizures). When MTLE begins in childhood, atrophy of the hippocampus can often be seen on magnetic resonance imaging (MRI) of the brain. When MTLE begins in adulthood, MRIs often reveal no visible abnormalities. Rarely, MTLE can be hereditary or related to brain tumors, spinal meningitis, encephalitis, head injury or blood vessel malformations. MTLE can occur in association with other brain malformations. Most often, a cause cannot be determined with certainty. LTLE is less common. It can be hereditary, as in Autosomal Dominant Lateral Temporal Lobe Epilepsy (ADLTLE) with auditory or visual features, but can also be associated with tumors, meningitis, encephalitis, trauma, vascular malformations or congenital brain malformations. Again, in many affected persons it is common that no cause can be identified. Symptoms The symptoms felt by the patient with TLE and the signs observable by others during seizures depend upon the specific areas of the temporal lobes and neighboring brain areas affected by the seizure. The 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. Syndrome of TLE The classical syndrome of TLE begins when there is a very early insult to the left or right hippocampus. Newborn babies may develop an infection resulting in a fever. Young babies have an immature thermoregulation system, and the fever causes the baby's core body temperature to increase. The raised body temperature can cause febrile convulsions. These are quite normal in babies, usually lasting only a few minutes, but in a few cases the convulsions can last for an hour. This is a sign that the infant is at a high risk of developing TLE. Treatments There are oral medications available for management of epileptic seizures, but with incompletely understood mechanisms of action. Anti-seizure drugs and sedatives may normalize neurological function and soothe the affected individual but may stifle the pronounced creativity and communication demonstrated by some individuals with TLE. The medications may also have extremely harsh side effects, including, but are not limited to, overall weakness (some are forced to use support devices such as canes), tremors, slurred speech, and loss of fine motor control. Some epileptics would rather have seizures while taking less medication than have their seizures be totally controlled and suffer the debilitating effects of these medications. Surgery, if applicable, may also be a viable alternative. Some patients experience depression and disengagement from self and environment upon normalization of the sometimes intensely inspirational, profoundly stimulating experiences that accompany TLE. Monitoring of treatment is done using EEGs, CT scans, MRI imaging, oral interviews, and coordination tests. Temporal Lobe Epilepsy and the Arts The intense emotions, sensory experience including vibrancy of colors, and particular mental state provoked by temporal lobe abnormalities may have contributed to the creation of significant works of art. Artists known (with varying degrees of certainty) to have had TLE include Charles Dodgson (a.k.a. Lewis Carroll), Edgar Allan Poe, Dostoevsky (whose novel The Idiot features an epileptic protagonist, Prince Myshkin), Vincent Van Gogh, Gustave Flaubert, Soren Kierkegaard and Sylvia Plath. The contemporary author Thom Jones has temporal lobe epilepsy. The left temporal lobe affects comprehension, naming, verbal memory and other language functions. Temporal Lobe Epilepsy, Neurotheology and Paranormal Experience The first researcher to note and catalog the abnormal experiences associated with TLE was neurologist Norman Geschwind, who noted a constellation of symptoms, including hypergraphia, hyperreligiosity, fainting spells, mutism and pedantism, often collectively ascribed to a condition known as Geschwind syndrome. Vilayanur S. Ramachandran explored the neural basis of the hyperreligiosity seen in TLE using galvanic skin response, which measures emotional arousal, to determine whether the hyperreligiosity seen in TLE was due to an overall enhanced emotional response, or if the enhancement was specfic to religious stimuli (Ramachandran and Blakeslee, 1998). By presenting subjects with neutral, sexually arousing and religious words while measuring GSR, Ramachandran was able to show that patients with TLE showed enhanced emotional responses to the religious words, diminished responses to the sexually charged words, and normal responses to the neutral words. These results suggest that the medial temporal lobe is specifcally involved in generating some of the emotional reactions associated with religious words, images and symbols. UFO Researcher Albert Budden and cognitive neuroscience researcher Michael Persinger assert that increases in local electromagnetism, triggering the temporal lobe can stimulate TLE and trigger hallucinations of apparent paranormal phenomena, for example ghosts and UFO's. Persinger has even gone as far as to create a "God helmet" to apparently demonstrate how stimulation of the parietal and temporal lobe can evoke altered states of consciousness. Quite possibly, as neurotheologians have speculated, then, individuals with temporal lobe epilepsy, who have a natural aptitude for "religious" states of consciousness (such as euphoria or samadhi) have functioned in human history as religious figures or as shamans. Persinger's theories, however, remain controversial. See also Media Depictions Further reading | |||||||
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