Seizure is the clinical manifestation of
an abnormal discharge of a population
of cells in the brain (neurons) that all fire
together. When a population of neurons
starts firing abnormally all together, this
electrical event can produce a manifestation in a person: the clinical features of a
seizure. Clinical features can be subjective – something that the patient notices
such as a rising feeling in the stomach, a
taste or a smell – and/or objective, such
as jerking of the limbs or loss of consciousness.
Epilepsy is a neurological disorder characterized by the occurrence of seizures
without acute provocation. Epilepsy is
common: 1 in 26 people develop epilepsy at some point in their lives. About
one-third of people still have seizures despite treatment with currently available
medications. Some people’s epilepsy can
be managed by surgery if an identifiable
region of the brain can be located where
the seizures originate, and that region can
be resected surgically. But many people
with epilepsy still have seizures despite
treatment efforts.
About two-thirds of epilepsy has no identified cause. Genetic factors may play a
critical role particularly in that subset of
epilepsy. Genetic research has begun to
offer a novel understanding of the causes
and the underlying biology of epilepsy.
That understanding can be used to develop targeted new treatments, and transform patient care.
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HeadW ise ®
|
Volume 4, Issue 4 • 2015
“Our results are the first
demonstration of a shared
genetic effect on migraine
and epilepsy in a large
group of individuals with
common epilepsy and
common migraine.”
this shared genetic cause was restricted to specific types of
migraine or epilepsy. First, we looked at migraine with aura
and migraine without aura. Migraine with aura (MA) is a
specific sub-type of migraine, where a person experiences
a warning sensation before the headache. A migraine aura
consists of reversible focal neurological symptoms. Those
symptoms, which can be quite varied, usually develop
gradually over 5 to 20 minutes and last for less than 60
minutes. The headache usually follows the aura symptoms.
The most common aura symptoms are visual symptoms,
such as bright flickering lights and geometric patterns
with impaired vision. Sometimes during an aura, patients
will be unable to see in a certain part of their visual field.
They may also experience loss of sensation on one side
of the body, tingling sensations, weakness on one side of
the body, inability to speak, or vertigo. It is important to
distinguish more dangerous neurological conditions that
can cause these symptoms before attributing the cause to
migraine.
Some people experience both headaches with aura and
without aura. In this study, we separated participants with
migraine into those who ever had auras (MA) from those
who never had an aura with their migraine headaches (MO
only). In our study, when we divided migraine types, we
found that the shared genetic effect between migraine and
epilepsy was specific to MA; in other words, MO-only did