contraction of the lower orbiculars is always accompanied, as we have
seen, by the drawing up of the upper lip. Had the upper lip, in fig. 6,
been thus acted on to a slight extent, its curvature would have been
less rigid, the naso-labial farrow would have been slightly different,
and the whole expression would, as I believe, have been more natural,
independently of the more conspicuous effect from the stronger
contraction of the lower eyelids. The corrugator muscle, moreover, in
fig. 6, is too much contracted, causing a frown; and this muscle never
acts under the influence of joy except during strongly pronounced or
violent laughter.
By the drawing backwards and upwards of the corners of the mouth,
through the contraction of the great zygomatic muscles, and by the
raising of the upper lip, the cheeks are drawn upwards. Wrinkles are
thus formed under the eyes, and, with old people, at their outer ends;
and these are highly characteristic of laughter or smiling. As a gentle
smile increases into a strong one, or into a laugh, every one may feel
and see, if he will attend to his own sensations and look at himself in
a mirror, that as the upper lip is drawn up and the lower orbiculars
contract, the wrinkles in the lower eyelids and those beneath the eyes
are much strengthened or increased. At the same time, as I have
repeatedly observed, the eyebrows are slightly lowered, which shows
that the upper as well as the lower orbiculars contract at least to
some degree, though this passes unperecived, as far as our sensations
are concerned. If the original photograph of the old man, with his
countenance in its usual placid state (fig. 4), be compared with that
(fig. 5) in which he is naturally smiling, it may be seen that the
eyebrows in the latter are a little lowered. I presume that this is
owing to the upper orbiculars being impelled, through the force of
long-associated habit, to act to a certain extent in concert with the
lower orbiculars, which themselves contract in connection with the
drawing up of the upper lip.
The tendency in the zygomatic muscles to contract under pleasurable
emotions is shown by a curious fact, communicated to me by Dr. Browne,
with respect to patients suffering from GENERAL PARALYSIS OF THE
INSANE.[811] In this malady there is almost invariably
optimism delusions as to wealth, rank, grandeur insane joyousness,
benevolence, and profusion, while its very earliest physical symptom is
trembling at the corners of the mouth and at the outer corners of the
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