第 36 节
作者:
忙 更新:2021-02-27 02:14 字数:9322
ears; raised up his two hands; blessed the goat; turned round; and without looking again; went away。
_On the cause of the obliquity of the eyebrows under suffering_。 During several years no expression seemed to me so utterly perplexing as this which we are here considering。 Why should grief or anxiety cause the central fasciae alone of the frontal muscle together with those round the eyes; to contract? Here we seem to have a complex movement for the sole purpose of expressing grief; and yet it is a comparatively rare expression; and often overlooked。 I believe the explanation is not so difficult as it at first appears。 Dr。 Duchenne gives a photograph of the young man before referred to; who; when looking upwards at a strongly illuminated surface; involuntarily contracted his grief…muscles in an exaggerated manner。 I had entirely forgotten this photograph; when on a very bright day with the sun behind me; I met; whilst on horseback; a girl whose eyebrows; as she looked up at me; became extremely oblique; with the proper furrows on her forehead。 I have observed the same movement under similar circumstances on several subsequent occasions。 On my return home I made three of my children; without giving them any clue to my object; look as long and as attentively as they could; at the summit of a tall tree standing against an extremely bright sky。 With all three; the orbicular; corrugator; and pyramidal muscles were energetically contracted; through reflex action; from the excitement of the retina; so that their eyes might be protected from the bright light。 But they tried their utmost to look upwards; and now a curious struggle; with spasmodic twitchings; could be observed between the whole or only the central portion of the frontal muscle; and the several muscles which serve to lower the eyebrows and close the eyelids。 The involuntary contraction of the pyramidal caused the basal part of their noses to be transversely and deeply wrinkled。 In one of the three children; the whole eyebrows were momentarily raised and lowered by the alternate contraction of the whole frontal muscle and of the muscles surrounding the eyes; so that the whole breadth of the forehead was alternately wrinkled and smoothed。 In the other two children the forehead became wrinkled in the middle part alone; rectangular furrows being thus produced; and the eyebrows were rendered oblique; with their inner extremities puckered and swollen; in the one child in a slight degree; in the other in a strongly marked manner。 This difference in the obliquity of the eyebrows apparently depended on a difference in their general mobility; and in the strength of the pyramidal muscles。 In both these cases the eyebrows and forehead were acted on under the influence of a strong light; in precisely the same manner; in every characteristic detail; as under the influence of grief or anxiety。
Duchenne states that the pyramidal muscle of the nose is less under the control of the will than are the other muscles round the eyes。 He remarks that the young man who could so well act on his grief…muscles; as well as on most of his other facial muscles; could not contract the pyramidals。'5' This power; however; no doubt differs in different persons。 The pyramidal muscle serves to draw down the skin of the forehead between the eyebrows; together with their inner extremities。 The central fasciae of the frontal are the antagonists of the pyramidal; and if the action of the latter is to be specially checked; these central fasciae must be contracted。 So that with persons having powerful pyramidal muscles; if there is under the influence of a bright light an unconscious desire to prevent the lowering of the eyebrows; the central fasciae of the frontal muscle must be brought into play; and their contraction; if sufficiently strong to overmaster the pyramidals; together with the contraction of the corrugator and orbicular muscles; will act in the manner just described on the eyebrows and forehead。
When children scream or cry out; they contract; as we know; the orbicular; corrugator; and pyramidal muscles; primarily for the sake of compressing their eyes; and thus protecting them from being gorged with blood; and secondarily through habit。 I therefore expected to find with children; that when they endeavoured either to prevent a crying…fit from coming on; or to stop crying; they would cheek the contraction of the above…named muscles; in the same manner as when looking upwards at a bright light; and consequently that the central fasciae of the frontal muscle would often be brought into play。 Accordingly; I began myself to observe children at such times; and asked others; including some medical men; to do the same。 It is necessary to observe carefully; as the peculiar opposed action of these muscles is not nearly so plain in children; owing to their foreheads not easily wrinkling; as in adults。 But I soon found that the grief…muscles were very frequently brought into distinct action on these occasions。 It would be superfluous to give all the cases which have been observed; and I will specify only a few。 A little girl; a year and a half old; was teased by some other children; and before bursting into tears her eyebrows became decidedly oblique。 With an older girl the same obliquity was observed; with the inner ends of the eyebrows plainly puckered; and at the same time the corners of the mouth were drawn downwards。 As soon as she burst into tears; the features all changed and this peculiar expression vanished。 Again; after a little boy had been vaccinated; which made him scream and cry violently; the surgeon gave him an orange brought for the purpose; and this pleased the child much; as he stopped crying all the characteristic movements were observed; including the formation of rectangular wrinkles in the middle of the forehead。 Lastly; I met on the road a little girl three or four years old; who had been frightened by a dog; and when I asked her what was the matter; she stopped whimpering; and her eyebrows instantly became oblique to an extraordinary degree。
'5' Mecanisme de la Phys。 Humaine; Album; p。 15。
Here then; as I cannot doubt; we have the key to the problem why the central fasciae of the frontal muscle and the muscles round the eyes contract in opposition to each other under the influence of grief;whether their contraction be prolonged; as with the melancholic insane; or momentary; from some trifling cause of distress。 We have all of us; as infants; repeatedly contracted our orbicular; corrugator; and pyramidal muscles; in order to protect our eyes whilst screaming; our progenitors before us have done the same during many generations; and though with advancing years we easily prevent; when feeling distressed; the utterance of screams; we cannot from long habit always prevent a slight contraction of the above…named muscles; nor indeed do we observe their contraction in ourselves; or attempt to stop it; if slight。 But the pyramidal muscles seem to be less under the command of the will than the other related muscles; and if they be well developed; their contraction can be checked only by the antagonistic contraction of the central fasciae of the frontal muscle。 The result which necessarily follows; if these fasciae contract energetically; is the oblique drawing up of the eyebrows; the puckering of their inner ends; and the formation of rectangular furrows on the middle of the forehead。 As children and women cry much more freely than men; and as grown…up persons of both sexes rarely weep except from mental distress; we can understand why the grief…muscles are more frequently seen in action; as I believe to be the case; with children and women than with men; and with adults of both sexes from mental distress alone。 In some of the cases before recorded; as in that of the poor Dhangar woman and of the Hindustani man; the action of the grief…muscles was quickly followed by bitter weeping。 In all cases of distress; whether great or small; our brains tend through long habit to send an order to certain muscles to contract; as if we were still infants on the point of screaming out; but this order we; by the wondrous power of the will; and through habit; are able partially to counteract; although this is effected unconsciously; as far as the means of counteraction are concerned。
_On the depression of the corners of the mouth_。This action is effected by the _depressores anguili oris_ (see letter K in figs。 1 and 2)。 The fibres of this muscle diverge downwards; with the upper convergent ends attached round the angles of the mouth; and to the lower lip a little way within the angles。'6' Some of the fibres appear to be antagonistic to the great zygomatic muscle; and others to the several muscles running to the outer part of the upper lip。 The contraction of this muscle draws downwards and outwards the corners of the mouth; including the outer part of the upper lip; and even in a slight degree the wings of the nostrils。 When the mouth is closed and this muscle acts; the commissure or line of junction of the two lips forms a curved line with the concavity downwards;'7' and the lips themselves are generally somewhat protruded; especially the lower one。 The mouth in this state is well repre