hy of attention.

Another reason why too prolonged use of the brain is so mischievous is
seen in a peculiarity, which is of itself a proof of the auto-activity
of the vital acts of the various organs concerned in intellection. We
sternly concentrate attention on our task, whatever it be; we do this
too long, or under circumstances which make labor difficult, such as
during digestion or when weighted by anxiety. At last we stop and
propose to find rest in bed. Not so, says the ill-used brain, now
morbidly wide awake; and whether we will or not, the mind keeps turning
over and over the work of the day, the business or legal problem, or
mumbling, so to speak, some wearisome question in a fashion made useless
by the denial of full attention. Or else the imagination soars away
with the unrestful energy of a demon, conjuring up an endless procession
of broken images and disconnected thoughts, so that sleep is utterly
banished.

I have chosen here as examples men whose brains are engaged constantly
in the higher forms of mental labor; but the difficulty of arresting at
will the overtasked brain belongs more or less to every man who overuses
this organ, and is the well-known initial symptom of numerous morbid
states. I have instanced scholars and men of science chiefly, because
they, more than others, are apt to study the conditions under which
their thinking organs prosper or falter in their work, and because from
them have we had the clearest accounts of this embarrassing condition of
automatic activity of the cerebral organs. Few thinkers have failed, I
fancy, to suffer in this way at some time, and with many the annoyance
is only too common. I do not think the subject has received the
attention it deserves, even from such thorough believers in unconscious
cerebration as Maudsley. As this state of brain is fatal to sleep, and
therefore to needful repose of brain, every sufferer has a remedy which
he finds more or less available. This usually consists in some form of
effort to throw the thoughts off the track upon which they are moving.
Almost every literary biography has some instance of this difficulty,
and some hint as to the sufferer's method of freeing his brain from the
despotism of a ruling idea or a chain of thought.

Many years ago I heard Mr. Thackeray say that he was sometimes haunted,
when his work was over, by the creatures he himself had summoned into
being, and that it was a good corrective to turn over the p