74

оп

Of the eight principal systems of the body four have almost always been selected as being the ones incriminated in the produ tion of Nightmare: the alimentary, the respiratory, the circulatory Th and the nervous. Many of the hypotheses emitted are now of only historical interest and need be no more than mentioned; such are for instance Lower's view that the condition is due to a collec tion of lymph in the fourth ventricle of the brain, Willis'" that in- P congruous matter from the blood mixes with the nervous fluid in the cerebellum, Fosgate's " that it is an affection of the anterior column of the spinal marrow and the nerves arising therefrom, Bailley's" that it is a distemper caused by undigested humors stopping the passage of the animal spirits, so that the body can not move, Hohnbaum's " that it is produced by poisonous gases or miasmata, Splittgerber's" that it occurs at certain phases of the moon, and Baillarger's" that it is due to primary congestion of the brain. Boschulte's" remarkable hypothesis, although of comparatively recent date, must also be classed in the same group. He writes: "Wir sehen also durch Stockung in den peripherischen Gefässen einen Druck auf die peripherischen Theile der Empfind ungsnerven veranlasst, dadurch aber, vermöge des mechanischchemisch-physikalischen Prozesses, die Empfindungen zwar parästhetisch erregt, aber in einem Theile des Centralnervensystems oder des Reflex-apparats die gebundene motorische Kraft nicht wirksam genug afficirt, während darauf der Reiz des Schellentons, in seiner proportionalen Stärke wirkend auf die specifische Energie des Gehörnerven, jene bis zum rölligen Erwachen entfesselt." The only modern writer who makes the nervous system responsible for the primary change is Rousset." He attributes the malady to an active congestion of the brain, brought about by fearful or excitable ideas of the preceding evening.

"Lower. Loc. cit.

To Willis. De anim. buctor, Cap. 6, p. 127.

70 Fosgate. Op. cit., p. 83.

"Bailley. English Dictionary, 1785. Art. Nightmare.

Hohnbaum. Psychische Gesundheit und Irresein in ihren Uebergängen, 1845, S. 38, 41.

79

80

Splittgerber. Loc. cit.

Baillarger. Mém de l'acad. de méd, 1846.

"Boschulte. Eine Mittheilung über Alpdrücken. Virchow's Arch. f. Path. Anat. u. Phys., Bd. LXXXV, S. 371.

82

Rousset. Op. cit., pp. 36, 37.

The earliest, and still most popular, medical hypothesis of the origin of Nightmare was that it arose from gastric disturbances. This view was originally brought forward by Galen," was elaborated by Paulus Aeginata" and is given as the orthodox medical one in the latest editions of Chamber's Encyclopedia," and of the Imperial Dictionary," where full accounts of it may be found. Practically all writers accept it, but so far as I am aware the only one who does so quite empirically is Binz," all others adding some hypothesis as to the mode of operation of the gastric disorder. As we shall presently see, there is a certain amount of truth in the empirical observation, but the commonly accepted hypotheses have little relation to what probably is the actual explanation of it. Two explanations have been offered, (1) that an over-full stomach presses on the diaphragm and thus mechanically impedes the circulation through the heart and lungs, and (2) that the presence of undigested food in the stomach acts as a peripheral source of irritation to the nervous system. That the former of these views, which has been maintained by Paulus Aeginata," Bond," Burton," Floyer," Macnish," Hodgkin," Scholz," Hammond," Herbert Spencer," Motet " and many others, is not the inclusive explanation it is often supposed to be was very convincingly demonstrated by Waller's self-observations. He says: "I religiously abstained, for many years, from eating anything after dinner, and took dinner

98

83 Galen. Comment. ad aph. Hipp. Ed. Kühn, XVII, 2. S. 628, u. 747. “Paulus Aeginata. Loc. cit.

"Chamber's Encyclopedia, 1902, Vol. IV, p. 89.

'Imperial Dictionary of the English Language, Vol. III, p. 260.

Binz. Ueber den Traum, 1878, S. 28.

Burton. Op. cit., Vol. I, Pt. 2, Sec. 2, Mem. 5, p. 434.

Sir James Floyer. Quoted by Latham. A Dictionary of the English

Language, 1882, Vol. I, p. 1240.

"Macnish. Op. cit., p. 134.

"Hodgkin. Loc. cit.

"Scholz. Schlaf und Traum, 1887, S. 30.

95

98

'Hammond. Op. cit., pp. 185, 187.

Herbert Spencer. Principles of Sociology, 1885, Vol. I, p. 133.

97 Motet. Loc. cit.

"Waller. Op. cit., pp. 11, 70, 75.

also at as early an hour as two o'clock. It was during this period that I suffered most from the disease." No one can accuse Waller, therefore, of not having put the over-full stomach hypothesis to adequate experimental proof, and he is unequivocal as to the results of his investigation. Both Macnish and Hodgkin strongly maintain the improbability of a full stomach interfering with the action of the heart to such an extent as seriously to embarrass the circulation, though they hold that it acts by mechanically impeding the respiration, a view the likelihood of which does not impress one at first sight. According to Macnish the stomach causes pressure on the diaphragm and torpor of the intercostal muscles, with consequent hindering of the pulmonary circulation.

104

102

The second explanation, which has been maintained by Paulus Aeginata," Waller,100 Barclay, Splittgerber, Radestock,TM Chambers, and Maudsley, is to the effect that indigestible or undigested food in the stomach acts by producing irritating afferent impulses, which on reaching the brain are transformed into feelings of terror. Strahl 10 describes the afferent impulses as being not of a nervous nature but as consisting in stomach gases which are carried to the brain and disturb its repose. The precise kind of indigestible food that is most efficacious in this connection is often described, for instance by Waller,107 with a fulness of detail that betokens a confidence of belief only too incommensurate with the value of the evidence on which it is founded. It is evident that this explanation is even harder to sustain than the last, for at the best it is obvious that there are gaps of considerable extent in the description of the mode of action of the morbid process.

Distention of the stomach is not the only way in which the circulation has been supposed to be embarrassed. Strümpell, Rade

"Paulus Aeginata. Loc. cit.

100 Waller. Op. cit., pp. 65, 75, 96, 98.

101

564.

108

Barclay. Universal English Dictionary. Revised by Woodward, p.

103 Splittgerber. Loc. cit.

103 Radestock. Op. cit., S. 129.

10 Chamber's Encyclopedia. Loc. cit.

105

Maudsley. The Pathology of Mind, 1879, p. 32.

10 Strahl. Der Alp, sein Wesen und seine Heilung, 1833.

107 Waller. Op. cit., pp. 105, 106, 109.

108 Strümpell. Die Natur und Enstehung der Träume, 1874, S. 116.

1

109

C: stock and others have attributed to a similar mechanism the frequency of Nightmares in cases of heart disease. Albers" holds that "determination of the blood to the chest," from whatever source, is the essential cause of Nightmare. A constrained posture He has frequently been invoked as the active agent in bringing about this state of embarrassment, for instance by Hammond," Radestock" and Scholz; "Radestock holds that the abnormal posture causes embarrassment of the heart directly, Hammond and Scholz that it does so only by impeding the circulation. Kant" formulated the remarkable opinion that Nightmare was a beneficent process the function of which was to wake the individual and so warn him of the danger to which he was exposed from the effect of the constrained posture of his circulation. As we shall presently learn, Freud also sees a teleological function, though of a vastly different kind, in the waking from Nightmare.

116

The supine posture even, normal and unconstrained, has been incriminated by some writers as the efficient agent in the production of Nightmare. This view was greatly elaborated by Bond," who founded on the basis of it a most complicated hypothesis concerning the mechanism of the circulation, and ascribed all sorts of harmful results to the dangerous practice of lying on the back. He asks, as Kant did, "Are not these monstrous dreams intended as a stimulus to rouse the sentient principle in us, that we might alter the position of the body, and by that means avoid the approaching danger?" Splittgerber "" and Rousset also consider the supine position is in itself harmful, though the latter ascribes to it only a predisposing role in that it sets up a passive congestion of the brain that allows active congestion to supervene and originate the attack. Waller," on the other hand, held that the

100 Radestock. Op. cit., S. 130.

110

117

118

Albers. Quoted by Feuchtersleben. The Principles of Medical Psychology. Sydenham Trans., p. 198.

importance of posture as a cause of embarrassment of respiration or of the circulation had been greatly overestimated, on the ground that he personally had repeatedly suffered from Nightmare in every position, even when sleeping with his head leaning forwards on a table.

121

122

Of late years there has been a reaction against the views that placed in the foreground the circulatory troubles, and that culminated in Maury's work, where the varying state of the cere bral circulation was made to account for most of the phenomena of sleep and dreams. As the result, mainly of the work of Boerner, attention has been more and more concentrated on the respiratory embarrassment as a chief factor in the production of Nightmare. Although the respiratory symptoms had long been noticed they had generally been thought, in the way expounded for instance by Rousset, to be secondary to the circulatory disturbance. Gradually, however, it was recognized that this might be produced by a primary respiratory trouble, as mentioned by Radestock in the case of asthma, and Cubasch indeed holds that with Nightmare this is invariably the case. Binz following Boerner, has developed what he calls a toxic theory of Nightmare, which he attributes to the poisoning of the brain by carbon dioxide. Prout also takes this position, and explains the frequency with which Nightmare occurs at midnight by the fact, he declares to have established, that the percentage of carbon dioxide in the blood is greatest at that time.

123

126

124

123

127

According to these observers, then, gastric disturbances would play only a very subsidiary role, and the views of Scholz, that Nightmare always arises from a disorder of either the respiratory or circulatory systems, or of Motet," who gives a long list of "causes " which, however, he says all act by impeding the circu

120 Maury. Le Sommeil et les Rêves, 1865.

121 Boerner. Op. cit.

122 Rousset. Op. cit., p. 37.

123 Radestock. Op. cit., S. 130.

124 Cubasch. Op. cit., S. 17, 18.

125 Binz. Op. cit., S. 27, 28.

10 Prout. Cited by Radestock. Op. cit., S. 129.

127 Scholz. Op. cit., S. 27.

128 Motet. Loc. cit.