CHAPTER XVI.

INSANITIES OF CRITICAL PERIODS.

By the insanities of critical periods we here understand those mental disorders directly connected with special periods of development or of the appearance and disappearance of important functions. Not all critical periods are associated with insanity, properly so called, that is characteristic in any way, or that calls for special notice here. Thus the second dentition, the passage from infancy to childhood, is a very important period of human development, but no author has yet attempted to include a special type of the insanities of this period. Nevertheless, it is at this special time many of the permanent degenerative stigmata begin to appear, and changes undoubtedly occur that lead later, in many cases, to profound physical and even mental defects. They are not, however, prominently noticeable at this particular age, and we therefore have no insanity of dentition even among the more elaborate etiologic classifications. The mental development at this period is undisturbed, and while brain changes certainly occur, they are not such as to affect the individual's mental health at the time.

It is different at the next great critical period, that of puberty and adolescence. Here the system has to accommodate itself to new functions and relations, and an entirely new range of mental activities is opened up. The imagination, the emotions, as well as the intellect, are stimulated and widened in their scope, the individual becomes, at it were, a new person, responsibilities are increased, and the intellect taxed as never before. In this stage of life, which really covers many

years, from the early awakenings of the sexual instinct to fully developed physical maturity, mental breakdown is a possibility and frequently also a realized fact. This is the chief critical period of human existence as far as the risk of mental derangement is concerned.

The climacteric, or change of life, when the reproductive activities cease, is usually also reckoned as a time when there is special liability to mental breakdown, and climacteric insanity in women has a place in nearly all our etiologic classifications of mental disease. This change is, however, in our opinion much more generally a physiologic one than is that of the instalment of this function, and. should, therefore, be less likely to be attended with so serious a derangement as insanity. In perfectly normal individuals this change ought to occur without disturbance, but such are rare, and there is very frequently, in the readjustment of the physical functions, a disturbance of the mental operations that in extreme cases or in those predisposed extends to actual mental disease. We cannot here, however, as in the case of insanity of adolescence, point out special characteristics of the mental derangement of this period that are so constant and recognizable as to give us a well-defined species. Climacteric insanity has, therefore, only an etiologic reason for its distinction, and our notice of it will, therefore, be more general and brief than that of the other types to be described as appertaining to critical periods.

Lastly we have the period of the decline of life, with its attendant physical and mental decay and failure. Here we have mental disorders of various types, but so related by their common causation that we can often recognize them as characteristic. Senile insanity, or rather senile insanities, have, therefore, a recognized place in our classification.

ADOLESCENT INSANITY (DEMENTIA PRAECOX,

HEBEPHRENIA).

The term adolescent insanity, as here used, covers a rather wide range of mental disorders which have been described by authorities under various names,-pubescent insanity, dementia præcox, hebephrenia, catatonia, etc.,-which all seem to us best included under one general head. The term adolescent is chosen as probably the best one to designate its general character, though in this it is not exact, as its incidence in time covers the whole period from puberty to early adult life. It is preeminently the insanity of development, or rather of its disorders; its dominant characteristic is the tendency to dementia, and it is on this that its definition must be based. Adolescent insanity is a group of morbid mental symptoms occurring at about the period of sexual development, with, in general, a somewhat characteristic affective type, tending to ultimate dementia with a more or less rapid course. Including, as we do here, not only the ordinary type of pubescent insanity, but also catatonia and some forms marked by delusional symptoms, a more close and accurate definition is not practicable. It is a species better described than defined, but one that exists and is familiar to the practical alienist.

It should be said here that there are sometimes considered under this head a number of borderland conditions that occur more or less frequently during the period of sexual development, but which we exclude, believing them to belong more properly elsewhere. Besides a common sort of pseudo-melancholia, some forms of sexual hypochondria and neurasthenia are to be reckoned among these, though the former is sometimes hardly anything more than a worrying about sexual matters due to misinformation and terrifying statements of quacks. True adolescent insanity is

preeminently a degenerative psychosis; these forms are not at all essentially connected with any real degeneracy inherited or acquired. The same may be said of some conditions due directly or indirectly to sexual bad habits or vice; they only require the cessation of their cause to insure their disappearance. Insanity from masturbation may occur, but it is generally in predisposed individuals, and the vice only an exciting cause, when it is not, on the contrary, simply an effect or symptom of the disease.

The form of derangement elsewhere described under the name of original paranoia, in connection with other paranoias or delusional insanities, has some apparent claim to be considered here. Appearing, as it does, during this period of developmental stress, and being also a peculiarly degenerative type, it might seem that it could also be properly reckoned as belonging to this group of adolescent derangements. Its nature and cause, however, are different; while its subjects are markedly defective, bordering even in some respects on imbecility, the condition is not a rapidly progressive one, if progressive at all, and its symptoms are widely different from those of the forms here under consideration.

It should also be noted here that not every case of mental derangement occurring between puberty and the twenty-fifth or thirtieth year is one of adolescent insanity. While this period has its own types, well marked as we believe, it is also a stage of life in which any mental weakness is liable to reveal itself in other non-typical ways. Many cases of recurrent or periodic insanity make their first appearance about this time, hysteric derangements may also date from this period, and under conditions of special strain the confusional or delirious psychoses may occur. Congenital paretic dementia may and generally does have its earliest manifestations about or near the age of puberty, and, in