Thalamus

“ Further it was objected, That it was hard to conceive how soft a body as the thalamus Opticus (being only a protuberance of the Medullary part of the Brain) could make such a difference in the Stress or tension of the fibres: But 'tis apparent that upon drawing the Nerve from it forward (according as 'tis situated and runs toward the Eye) the Superior fibres are more upon the Stress than the lateral, and Nature in these cases is finer in her operations (or to speak more properly the great Author of Nature is) then we are in our Conceptions of them. ”

“ If, under the light of these facts, it be difficult to maintain that the seat of consciousness is not diffused through the central parts of the cerebrum and of the spinal cord, the pathological fact that in the human being the optic thalamus or the corpus striatum may be fundamentally changed in consistence and structure by disease, without loss of consciousness, is a barrier against the acceptance of Dr. ”

“ As the fibres of the medulla pass up through the pons to the great inferior ganglion, and the fibres of the corpus striatum pass outward and upward to form the cerebrum, this procession of the fibres is shown in the annexed engraving, in which we see the restiform bodies passing up to form the cerebellum, and the remainder of the medulla fibres passing through the pons, and then, under the name crus cerebri or thigh of the cerebrum, passing through the thalamus and striatum to expand in the left hemisphere of the cerebrum. ”

“ When the nervous system is relaxed in slumber so that sense impressions carried by the fibrous nerves are directed by the ganglionic nerves at random to different portions of the cortex of the brain, sense impressions are produced upon that organ which result in dreams, and the imagination of the sleeper revels in wonderland. As these are of nightly occurrence, and all men dream, the ghosts of dreamland that fill the sleeping life are remembered in many a revery of the waking life. ”

“ IX. That the Astral body of the medium, partaking of the nature of the Astral substance, may be extended from the physical body, may act outside of the latter, and may also extrude at times any portion of itself such as hand, arm, or leg and thereby move objects, indite letters, produce touches on the body, and so on ad infinitum. And that the Astral body of any person may be made to feel sensation, which, being transmitted to the brain, causes the person to think he is touched on the outside or has heard a sound. ”

“ The void that separates the pulp of the material nerve from consciousness is broader than the solar universe, for even from the most distant known star we can imagine the never-ending flight of a ray of light, that has once started on its travels into space. Can any man outline the bridge that connects the intellect with nerve or brain, mind, or with any form of matter? The fact that the surface of the bodies of some animals is capable of performing the same functions for these animals that the eye of man performs for him, is not more mysterious than is the function of that eye itself. ”

“ When during sleep our sensory organs are exposed to external irritants the impressions physically produced are transmitted to the brain by the nervous system and react in dreams as they would in the waking state, except that the reactions in the two states of consciousness—the dream state and the waking state—differ in proportion as the two states differ; but in both the Ego is the real percipient. ”

“ The difference, therefore, between waking thought and a dream is analogous to the difference between a page upon which the words have been arranged in a rational order, and another page upon which some of the same words have been set down at random. Inasmuch as the majority of our sensations are derived through the organs of sight, and since the larger portion of the sensory region of the cortex of the brain is concerned in the act of vision, it is no more than might be expected that the ideas suggested in sleep should generally proceed from the visual apparatus of the brain. ”

“ The machinery for dreaming planted in the human brain was not planted for nothing. That faculty, in alliance with the mystery of darkness, is the one great tube through which man communicates with the shadowy. And the dreaming organ, in connexion with the heart, the eye, and the ear, compose the magnificent apparatus which forces the infinite into the chambers of a human brain, and throws dark reflections from eternities below all life upon the mirrors of the sleeping mind. ”

“ But whether we assume one or other we postulate an unsleeping consciousness within ourselves while the brain is asleep: and that unsleeping creature was either the creator of the dream or the actor in a real event. Who is that unsleeping creature? Is it the same being who daily inhabits the brain? Does it rise up when the body sinks on the couch? Has it a dual life as we have when waking, when half our consciousness is of an external nature and half of subjective emotions and thoughts? Are part of our dreams internal fantasy and part perceptions of an external sphere of being? ”

“ They are enacting dreams. They are in truth working with infinitely greater [14] speed and power when we are asleep than when we are awake!
If, then, the brain hemispheres are waking above and the body is sleeping below, the communication between them must be severed by sleep at some part of the mechanism below the brain hemispheres (which are the mechanism of the Intelligence) and the point where the brain branches into the nerve system—which is the mechanism by whose action the vital force forms and sustains the organic structure. ”

“ Could the feeling of dream-flight be partly interpreted by organic memory of conditions of life more ancient than man,—life weighty, and winged, and flying heavily, a little above the ground?
Or might we suppose that some all-permeating Over-Soul, dormant in other time, wakens within [Pg 232] the brain at rare moments of our sleep-life? The limited human consciousness has been beautifully compared to the visible solar spectrum, above and below which whole zones of colors invisible await the evolution of superior senses ”

“ You see nothing, but only by a sensation that conjures up an image in your own brain, or optic nerve (as in a nightmare) , have an apparition, in consequence of which, as again in the nightmare, you are forced to believe for the moment, and are inclined to infer the existence of a corresponding reality out of your brain, but by what intermediation you cannot even form an intelligible conjecture. During the years of ill-health from disturbed digestion, I saw a host of apparitions, and heard them too—but I attributed them to an act in my brain. ”

“ Secondly, There is a great wildness and inconsistency in our dreams. For the brain, during sleep, is in a state so different from that in which the usual associations were formed, that they can by no means take place as they do during vigilance. On the contrary, the state of the body suggests such ideas, amongst those that have been lately impressed, as are most suitable to the various kinds and degrees of pleasant and painful vibrations excited in the stomach, brain, or some other part. ”

“ Now the process of dying, or the spirit's departure from the body, was fully commenced. The brain began to attract the elements of electricity, of magnetism, of motion, of life, and of sensation, into its various and numerous departments. The head became intensely brilliant; and I particularly remarked that just in the same proportion as the extremities of the organism grow dark and cold, the brain appears light and glowing.
Now I saw, in the mellow, spiritual atmosphere which emanated from and encircled her head, the indistinct outlines of the formation of another head. ”

“ Most dreams are stimulated from the blood into the nerves and the nerve-centers. And the heart is the transmission station. For the blood has a unity and a consciousness of its own. It has a deeper, elemental consciousness of the mechanical or material world. In the blood we have the body of our most elemental consciousness, our almost material consciousness. And during sleep this material consciousness transfers itself into the nerves and to the brain. The transfer in wakefulness results in a feeling of pain or discomfort—as when we have indigestion, which is pure blood-discomfort. ”

“ As, on a hot day in summer, when the equatorial draught has ceased to guide the wind, we may observe all manner of local tides among the masses of vapor which arise from the earth, so, in sleep, when the guiding influence of the senses is withdrawn, the ideas that still arise are chiefly dependent for their origin and association upon the automatic and endogenous activities of the brain. Undisturbed by impulses from the external world, the brain seems then to become more sensitive to impressions that have their origin within the body. ”

“ Rendered phosphorescent by the Astral Light, our brains swarm with innumerable reflections and images. We close our eyes, and it may happen that some brilliant, sombre or terrific panorama will unroll beneath our eyelids. He who is sick of a fever will scarcely close them through the night without being dazzled by an intolerable brightness. Our nervous system—which is a perfect electrical apparatus—concentrates the light in the brain, being the negative pole of that apparatus, or projects it by the extremities which are points designed for the circulation of our vital fluid. ”

“ In the same way, perhaps, can be explained the so-called telepathic powers of those gifted beings who can see what is happening in other places- perhaps on the other side of the world—clairvoyants, or what you will. Their brains are tuned to receive sight waves that need no optic nerves—waves that make no primary impression upon the retina of the eye at all, but are received direct by the brain itself. ”

“ These cases form an ascending series which illustrates the receptive and constructive capacities of the human brain when its sensory apparatus has become unusually or morbidly excitable. But this preternatural mobility may display itself in other departments besides those of mere sense-perception. The sphere of pure intellect may thus be invaded by ideas springing from impressions which address the reasoning faculties alone, so that in sleep a dream may lead the judgment to decisive conclusions that were scarcely recognized or heeded during the hours of wakefulness. ”

“ Is not the horizontal posture of the Body, which produces a Plethora in the Vessels of the Brain, and many odd sensations, the most general cause of dreams? Do they ever dream, who sleep in an erect position? Are not the luxurious and the plethoric most subject to disagreeable dreams? Is not the motion and titillation of the Animalculæ in Semine Masculino, the cause of the agreeable dreams which attend nocturnal emissions? ”

“ It would seem, then, that the currents from the periphery normally awaken a kind of brain-activity which the currents from other convolutions are inadequate to arouse. To this sort of activity—a profounder degree of disintegration, perhaps—the quality of vividness, presence, or reality in the object of the resultant consciousness seems correlated.
The Exteriority of Objects of Sensation.—Every thing or quality felt is felt in outer space. It is impossible to conceive a brightness or a color otherwise than as extended and outside of the body. Sounds also appear in space. ”

“ Our latent psychic possessions, among which dreams move, would seem to be by no means always at the same depth; the specific gravity of consciousness, as it were, varies, and these latent elements rise or fall, becoming nearer to the conscious surface or falling further away from it. But the greatest change must take place when the waking surface is reached and the outer world breaks on sleeping consciousness. In that change there is doubtless a process of necessary and automatic transformation and interpretation. ”

“ Every now and then a dream of different stuff is woven in the sleeper's brain: that part of it—the subliminal self, or whatever it may be—which never wholly slumbers, is vividly astir, sends its message through the sleeping brain like bubbles rising in still, placid water, rising equally and sanely to the surface in undisfigured rotundity. ”

“ But suppose an accident which upsets the equilibrium maintained by the brain between the external stimulation and the motor reaction, relax for a moment the tension of the threads which go from the periphery to the periphery by way of the centre, and immediately these darkened images come forward into the full light: it is probably the latter condition which is realized in any sleep wherein we dream. ”

“ Although the spirit leaves the body in sleep as previously stated, there is still a magnetic connection with soul and body. This magnetic connection acts on the sympathetic nervous system and the cerebro spinal which controls the functions of the human organism. In sleep the astral man may be in the immediate vicinity of his sleeping recuperating physical body or it may be thousands of miles away in space, the magnetic connection still exists regardless of the distance. ”

“ When the brain attracts powerfully some series of images analogous to any passion which has disturbed the equilibrium or the machine, the interchange of light stops, astral respiration ceases and the misdirected light coagulates, so to speak, in the brain. It comes about for this reason that the sensations of hallucinated persons are of the most false and perverse order. Some find enjoyment in lacerating the skin with thongs and in roasting their flesh slowly; others eat and relish things unfit for sustenance. ”