CAUSES OF EPILEPSY
"Find out the cause of this effect,
Or rather say, the cause of this defect,
For this effect defective comes by cause."
"Hamlet," Act II.
THE MECHANISM OF THE FIT
The brain consists of cells of _grey matter_, grouped together to form
centres for thought, action or sensation, and _white matter_, consisting of
nerve strands, which act as lines of communication between different parts
of brain and body. The wrinkled surface (_cortex_) of the brain, is covered
with grey matter, which dips into the fissures. There are also islands of
grey matter embedded in the white.
The front part of the brain is supposed, with some probability, to be the
seat of intelligence, while a ribbon three inches wide stretched over the
head from ear to ear would roughly cover the Rolandic area, in which are
contained the _motor cells_ through which impulse is translated to action.
These motor cells are controlled by _inhibitory cells_, which act as brakes
and release nerve energy in a gentle stream; otherwise our movements would
be convulsive in their violence, and life would be impossible through
inability usefully to direct our energy.
That is how inhibition acts physically; mentally it is the power to
restrain impulses until reason has suggested the wisest course.
Irritation of the cortex, especially the motor area, causes convulsions,
and experiment has shown that epilepsy may be due to a disease or
instability of certain inhibitory cells of the cortex. The motor cells of
epileptics are restrained, with some difficulty, by these cells in normal
times. When irritation from any cause throws additional strain on the motor
cells, the defective brakes fail, and the uncontrolled energy, instead of
flowing in a gentle stream through the usual channels, bursts forth in a
tidal wave through other areas of the brain, causes unconsciousness, and
exhausts itself in those violent convulsions of the limbs which we term a
fit.
The Primary Cause of epilepsy is an inherent instability of the nervous
system.
Secondary Causes are factors which cause the first fit in a person with
predisposing nervous instability; later, the brain gets the _fit habit_,
and attacks recur independently of the secondary cause. In most cases no
secondary causes can be discovered, and the disease is then termed
_idiopathic_, for want of an explanation.
Injuries to the brain may cause epilepsy, and many cases date from birth, a
difficult labour having caused a minute injury to the brain.
Some accident is often wrongly alleged as the cause of fits, for most
victims come of a bad stock, and when the first fit occurs, their relatives
recollect an injury or a fright in the past, which is said to be the cause.
Great fright may cause epilepsy, as in the case of a nervous girl whose
brother entered her room, covered with a sheet, as a "ghost", a "joke" that
was followed by a fit within an hour.
Sunstroke may cause fits, and a few cases follow infectious diseases.
Alcoholism is a strong secondary factor, fits often occurring during a
drinking-bout and in topers, but in many cases, drunkenness, instead of
being the cause, is only the result of a lack of self-control following
epilepsy.
Pregnancy may be a secondary cause of the malady: it may lead to more
frequent and severe seizures in women who are already victims; bring on a
recurrence of the malady after it has apparently been cured; or, very
rarely, induce a temporary or permanent cure.
Epilepsy may be due to abortives. These drugs wreck the constitution of the
undesired children, who contract epilepsy from causes which would not so
have affected them had they started fairly. In many families, the first
child, who was wanted, is normal; some or all the others, who were not
desired and on whom attempts were probably made to prevent birth, are
neuropaths, as are many illegitimate children. It cannot too emphatically
be stated that there is no drug known which will procure abortion without
putting the woman's life in so grave a danger as to prevent medical men
using it; legal abortion is always procured surgically. Dealing in
abortifacients would be a capital offence under the laws of a rational
community.
Self-abuse may perhaps play some part in epilepsy commencing or recurring
after the age of ten.
The onset of menstruation often coincides with the onset of epilepsy, and
in some cases irregularity of the menses seems to be a secondary or
exciting cause.
Exciting Causes aggravate the trouble when present, causing more frequent
and severe seizures. The chief are irritation of stomach and bowels (from
decaying teeth, unchewed, unsuitable, or indigestible food, constipation,
or diarrhoea), exhaustion, work immediately after a meal, passion or
excitement, fright, worry, mental work, alcoholism, sexual excess, nasal
growths, eye-strain; in short, anything that irritates brain or body.
Theories as to Cause. Epilepsy is usually classed as a _functional
disorder_; that is, the brain cells are physically normal, but, for some
unknown reason, they act abnormally at certain times. This term is a very
loose one, and there is reason to believe that the basis of epilepsy is
some obscure disease of the brain which has not been detected by present
methods.
The new school of psychologists regard the malady as a mental _complex_--a
system of ideas strongly influenced by the emotions--the convulsions being
but minor symptoms.
Fits are most frequent between 9-10 p.m. the hours of deepest repose. One
school says this is due to anæmia of the brain during sleep. Clark traces
the cause to lessened inhibitory powers owing to the higher brain centres
being at rest, while Haig claims to have explained the high incidence at
this hour by the fact that uric acid is present in the system in the
greatest amount at this time.
Some doctors have thought, on the contrary, that _excess_ of blood in the
head was the cause, but results of treatment so directed did not bear out
the sanguine hopes built on the theory.
The fact that convulsions occur in diabetes and alcoholism, suggested that
epilepsy was due to poisons circulating in the blood, and thus irritating
the brain. Every act uses up cell material and leaves waste products,
exactly as the production of steam uses up coal and leaves ashes. Various
waste products have been found in more than normal quantities in the blood
of epileptics, but it is uncertain whether accumulation of waste products
causes the seizure.
A convincing theory must satisfactorily account for all the widely diverse
phenomena seen in epilepsy, and the problem must remain largely a matter of
speculation, until research work has given us a far deeper insight into the
biochemistry of both the brain cells, and the germ-plasm than we have at
present.
* * * * *