I once had the unusual, though unhappy, opportunity to observe the same phenomenon in the brain structure of a man who, in a paroxysm of alcoholic excitement, decapitated himself under the wheel of a railway carriage, causing his brain to instantaneously evolve from his skull. Within three minutes of the man's death, I saw the entire brain in front of me. It exhaled the odor of spirit most distinctly, and its membranes and minute structures were vascular in the extreme. The appearance suggested a recent injection of vermilion. When incised, the white matter of the cerebrum, studded with red points, was barely distinguishable from its natural whiteness, and the pia-mater, the internal vascular membrane covering the brain, resembled a delicate web of coagulated red blood due to the tense engorgement of its fine vessels.
I should note that this condition affected both the larger and smaller brain regions, the cerebrum and cerebellum, but it did not exhibit the same symptoms in the medulla or the beginning portion of the spinal cord.
The spinal cord and nerves.
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Alcohol's effects extended beyond the initial stage, influencing the spinal cord's function. This part of the nervous system enables us to perform automatic, mechanical acts systematically, even when we are thinking or speaking about other subjects. A proficient worker consistently executes their mechanical tasks flawlessly, even when their thoughts shift to other topics. Similarly, we all carry out our actions in an entirely instinctive manner, without necessitating the assistance of higher centers, unless an extraordinary event arises that necessitates their involvement, prompting us to deliberate before acting. Alcohol influences the spinal centers, leading to the correct continuation of these pure automatic acts. In order for the hand to reach any object or the foot to be correctly planted, the higher intellectual center must be invoked to make the proceeding secure. This quickly leads to a deficiency in the coordination of muscular movement. Certain muscles lose their nervous control, and the nervous stimulus weakens significantly. The muscles of the lower lip in the human subject usually fail first of all, then the muscles of the lower limbs, and it is worthy of remark that the extensor muscles give way earlier than the flexors. The muscles themselves, by this time, are also failing in power; they respond more feebly than is natural to the nervous stimulus; they, too, are coming under the depressing influence of the paralyzing agent; their structure is temporarily deranged, and their contractile power is reduced.
This modification of the animal's functions under alcohol marks the second degree of its action. In young subjects, there is now, usually, vomiting with faintness, followed by gradual relief from the burden of the poison.
Effect on the brain centers.
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The alcoholic spirit carried yet a further degree; the cerebral or brain centers become influenced; they are reduced in power, and the controlling influences of will and of judgment are lost. The unbalanced and chaotic state of these centers causes the rational part of a man's nature to yield to the emotional, passionate, or organic part. Now, the reason is absent or deceived by duty, revealing all the primal instincts and sentiments. The coward shows up more craven, the braggart more boastful, the cruel more merciless, the untruthful more false, the carnal more degraded. "In vino veritas expresses, even to physiological accuracy, the true condition." The reason, the emotions, the instincts are all in a state of carnival and in chaotic feebleness.
Finally, the alcohol's action continues, overwhelming the superior brain centers, clouding the senses, perfecting the voluntary muscular prostration, losing sensibility, and reducing the body to a mere log, dead by all but one-fourth, on which alone its life hangs. The heart still remains true to its duty, and while it just lives, it feeds the breathing power. And so the circulation and the respiration in the otherwise inert mass keep the mass within the bare domain of life until the poison begins to pass away and the nervous centers to revive again. It is happy for the inebriate that, as a rule, the brain fails so long before the heart that he has neither the power nor the sense to continue his process of destruction up to the act of death of his circulation. Therefore, he lives to die another day.
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