Epilepsy (often referred to as a seizure disorder) is a chronic neurological condition characterized by recurrent unprovoked seizures. The condition is named from the Greek epilepsia ("a taking hold of or seizing"). It is commonly controlled with medication, although experimental surgical methods are slowly gaining acceptance.
In the past, epilepsy has been associated with religious experiences and even demonic possession. Historically, epilepsy was called the "Sacred Disease" because people thought that epileptic seizures were a form of attack by demons, and that the visions epileptics experienced were sent by the Gods. Hippocrates remarked that epilepsy would be considered divine only until it was understood [1] (http://quote.wikipedia.org/wiki/Hippocrates).
Types of seizures
Epileptic seizures are classified both by their patterns of activity in the brain and their effects on behaviour.
In terms of their pattern of activity, seizures may be described as either partial (focal) or generalised. Partial seizures only involve a localised part of the brain, whereas generalised seizures involve the entire cortex. The term 'secondary generalisation' may be used to describe a partial seizure that later spreads to the whole of the cortex and becomes generalised.
Partial seizures may be further subdivided into both simple and complex seizures. This refers to the effect of such a seizure on consciousness; simple seizures cause no interruption to consciousness (although they may cause sensory distortions or other sensations), whereas complex seizures interrupt consciousness. This does not necessarily mean that the person experiencing this sort of seizure will fall unconscious (like fainting). For example, complex partial seizures may involve the unconscious repetition of simple actions, gestures or verbal utterances.
The effects of partial seizures can be quite dependent on the area of the brain in which they are active. For example, a partial seizure in areas involved in perception may cause a particular sensory experience (for example, the perception of a scent, music or flashes of light) whereas, when centred in the motor cortex, a partial seizure might cause movement in particular groups of muscles. This type of seizure may also produce particular thoughts or internal visual images or even experiences which may be distinct but not easily described. Seizures centred on the temporal lobes are known to produce mystical or ecstatic experiences in some people. These may result in a misdiagnosis of psychosis or even schizophrenia, if other symptoms of seizure are disregarded and other tests are not performed. Unfortunately for those with epilepsy, anti-psychotic medications prescribed without anti-convulsants in this case can actually lower the seizure threshold further and worsen the symptoms.
In about half of cases of temporal lobe epilepsy, very strong ictal headaches[2] (http://www.epilepsy.com/articles/ar_1063754930.html) may occur, often misdiagnosed as migraine with aura. However, these headaches may be much more intense, and are sometimes even accompanied by temporary blindness.
Common Neurological Disorders
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