Insanity : its classification, diagnosis, and treatment; a manual for students and practitioners of medicine / by E. C. Spitzka.

  • Spitzka, E. C. (Edward Charles), 1852-1914.
Date:
1887
Catalogue details

Licence: Public Domain Mark

Credit: Insanity : its classification, diagnosis, and treatment; a manual for students and practitioners of medicine / by E. C. Spitzka. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    plained of by hypochondriacal and demented paretic pa- tients, the voices commanding the sacrifice of relatives or self to insane fanatics, and those driving the melancholiac to the commission of suicide, are among the more charac- teristic examples of hallucinations in the insane. In all these cases there are no objective grounds for the percep- tion. An illusion is the perception of an object actually present, but in characters which that object does not really possess. The delu- sion of a hypochondriacal patient that he is decaying, be- cause he detects a decaying smell, while there is in reality a chronic catarrh of his naso-pharyngeal passages, resulting in a bad though not a putrid odor, is founded on an illu- sion; the patient who, hearing the wagons rolling on a street imagines that his name is being repeated in regular rhythm, has illusions; and the melancholiac who, seeing the appre- hensive glances of his relatives, imagines that they sneer at and threaten him, is suffering from the same class of symp- toms. In short, while the hallucination, as far as the outer world is concerned, is a creation out of nothing and entire- ly fictitious, the illusion is but a misinterpretation of a phy- siological impression and has a partial basis in fact. In the strictest psycho-physiological sense an hallucina- tion is a morbidly intensified memory. Gray nervous mat- ter, wherever situated, if connected with a sensory periph- ery, is capable of receiving and retaining impressions. The length-of time through which the impression may be re- tained differs in different segments of the central nervous apparatus. When, for example, a person looks at a window with a black figure standing in front of it distinctly out- lined against a very bright sky, and, after regarding it for a certain length of time fixedly, shuts his eyes and turns away, he will find the image still continuing. It gradually becomes fainter, but may last for several minutes. The fact that the retinal after-image follows the movements of the eyeball shows that it has its seat in the retina, and proves that the ganglionic cell layer of that ocular tunic is capable not only of receiving impressions but also of retaining them for a brief period of time. Now let a person be immured in absolute darkness for a week; let him, without exposing his retina to any other impression, repeat the experiment, and it will be found that the retinal after-image will last very much longer! In short, the less the nerve-cells of the retina are subjected to the rapidly-succeeding, quickly-inter-