certain geological compositions of the soil (cretinism occurs frequently in countries where the soil is composed of schistose clay or of streaked sandstone); poor quality of the water, which in the endemic sections is poorly aerated, deprived of iodine, and charged with calcium and magnesium salts; want; heredity.

All these causes, the influence of which should be kept in view, probably only prepare the soil for the action of some specific agent still unknown. According to the opinion of Griesinger, "endemic goitre and cretinism are specific diseases produced by a toxic cause of miasmatic nature.". This attitude certainly most nearly corresponds to the modern medical consensus of opinion and has at present the greatest number of adherents. In fact one cannot fail to note the similarity which exists between the etiology of endemic goitre and that of other endemic diseases of parasitic or, as Griesinger says, miasmatic origin, such as malaria.

The symptoms of cretinism usually appear in early childhood. Sometimes the onset is acute, so that the destruction of the gland is accomplished in a few days. Such was the case reported by Shields,1 in which an acute thyroiditis caused the destruction of the thyroid gland and resulted in cretinism.

Much more frequently the process is insidious, and it is impossible to ascertain the exact date of onset.

The size of the goitre is variable. The swelling may be slight, scarcely perceptible, or so enormous as to completely disable the patient. Resulting usually from a degeneration of the thryoid gland, it becomes

1 A Case of Cretinism Following an Attack of Acute Thyroiditis. New York Med. Jour., Oct. 1, 1898.

evident at about the sixth or eighth year of age and increases up to the time of puberty or even later.

Simple atrophy of the gland is much less frequent and is seen chiefly in sporadic cases.

Physically the cretin exhibits, in addition to the changes in the thyroid gland, the following symptoms: the stature is below the normal; the face is pale, puffed, or marked precociously with senile wrinkles; the pilous system is poorly developed; the mucous membranes are pale, anæmic, and thickened; the teeth are abnormal in shape and in implantation and subject to caries; puberty is retarded or even absent, and the cretin may remain infantile all his life.

Psychically we encounter all degrees of idiocy and imbecility. It seems, however, that the cretin is less impulsive, more manageable, and more capable of emotional activity than the ordinary idiot or imbecile.1

The brains of creting present no known specific lesions; asymmetry and various malformations of the hemispheres are frequent.

The treatment consists in thyroid medication, the results of which are the more perceptible the earlier it is instituted.

1 Bourneville. Progrès médical, 1897.
2 Ibid., 1890.

CHAPTER XX.

MISCELLANEOUS GROUPS (Continued).

MENTAL DISORDERS DUE TO ORGANIC CEREBRAL AFFECTIONS.

ALL the so-called organic cerebral affections, whether diffuse or localized, have an influence upon the psychic functions.

The most important among those which have not already been considered are tumors, multiple sclerosis, brain abscess, and central neuritis.

Tumors, when small and of slow growth, may give rise to no mental symptoms.. In other cases the mental state presents certain peculiarities which may aid in the diagnosis: Dupré and Devaux1 have found that "patients suffering from cerebral tumor present a peculiar state of mental depression and enfeeblement, which constitutes their dominant psychopathic note: this state is one of torpor, psychic dullness, and clouding of the intellect, to which may be added mental puerilism." Properly speaking these cases present no true dementia until the affection has reached its terminal period. According to the same authors 2 "the intelligence, though clouded, is, however, not destroyed. It responds to strong stimuli, to imperious injunctions; it is veiled, but nevertheless present, and not

1 Nouvelle iconographie de la Salpêtrière Tumeur cérébrale. 1901, Nos. 2 and 3, p. 51.

2 Loc cit., p. 8.

until the last phases of the development of the affection does it decline and finally disappear."

The diagnosis of brain tumor is based chiefly on the neurological symptoms; these are usually classified into general symptoms, common to all tumors and resulting from increase of intracranial pressure, severe and persistent headache, slow pulse, vertigo, vomiting, and gradual impairment of vision due to optic neuritis, and focal symptoms, varying with the location of the tumor, Jacksonian epilepsy, monoplegia, hemiplegia, aphasia, apraxia, hemianopsia, oculo-motor paralysis, etc.

The differentiation between brain tumor and general paresis may present considerable difficulty, the more so in view of the fact that in the case of tumors involving the meninges the cerebro-spinal fluid, as in general paresis, may show an increase of cellular elements. The application of the Wassermann reaction may aid materially in the diagnosis.

Multiple sclerosis may be accompanied by a gradually progressive mental deterioration simulating that of general paresis. In such cases too the application of the Wassermann reaction may aid in the diagnosis.

Brain abscess occurs chiefly as a complication of chronic purulent otitis media. The symptoms are slow pulse, localized headache, fever of the asthenic type, often subnormal temperature; mentally there are dullness, confusion, restlessness, and in severe cases coma. The abscess is generally located either in the temporal lobe when amnesic aphasia is a prominent symptom if the lesion is on the left side or in the cerebellar hemisphere causing vomiting, vertigo, and staggering gait. The diagnosis rests upon a history of chronic

otitis media, the symptoms here enumerated, and a microscopical examination of the blood which generally reveals leucocytosis; an exploratory operation may be necessary and should be done early in every case in which this condition is suspected.

3

Central neuritis. Cases of this highly interesting though rather rare condition have been reported by Wiglesworth, Meyer, Worcester, Turner, Cotton and Southard, Somers and Lambert, and others. The first systematic clinical and anatomical study was made by Meyer.7

Although clinically this condition is not very well defined and varies a good deal in its aspect, the anatomical changes found post mortem are highly characteristic and constitute the basis of its autonomy.

These changes are revealed only on microscopic examination and consist in widespread parenchymatous degeneration of the central nervous system unaccompanied by any inflammatory reaction. Large nerve

1 J. Wiglesworth. On the Pathology of Certain Cases of Melancholia Attonita, or Acute Dementia. Journ. of Ment. Sc., Oct., 1883.

2 Adolf Meyer. Demonstrations of Various Types of Changes in the Giant Cells of the Paracentral Lobules. Amer. Journ. of Ins., Oct., 1897.

3 W. L. Worcester. A Case of Landry's Paralysis. Journ. of Nerv. and Ment. Dis., 1897.

4 John Turner. Note on a Form of Dementia Associated with a Definite Change in the Appearance of the Pyramidal and Giant-Cells of the Brain. Brain, 1899.

5 H. A. Cotton and E. E. Southard. A Case of Central Neuritis with Autopsy. Trans. of the Amer. Med.-Psychol. Ass'n, 1908.

6 E. M. Somers and C. I. Lambert. Central Neuritis. State Hosp. Bulletin, December, 1908.

7 Adolf Meyer. On Parenchymatous Systemic Degenerations Mainly in the Central Nervous System. Brain, 1901.