It will be observed that, based somewhat on the conceptions of Griesinger, states of mental excitement were generally characterized as mania and all depressions as melancholia. As has been shown, the view that there was some definite relation between these two conditions had been gaining ground for many years and culminated in the "circular insanity" concept. In the meanwhile over fifty varieties of mania and thirty forms of melancholia were described by various authors. Aside from an emotional exaltation and increased psychomotor activity, few definite characteristics were insisted upon in a consideration of mania. There was almost invariably a disturbance of sleep but always with a sense of well-being and no feeling of exhaustion. The milder type of the disease was often referred to as "hypomania." In the more severe forms varying grades of violence developed. There was at times a clouding of the sensorium, a temporary appearance of hallucinations of sight and hearing, delusions of a persecutory or grandiose nature and incoherence of speech. Impulsive acts occasionally were noted during the height of the excitement. These attacks were frequently preceded by brief periods of depression. Many cases made rather early recoveries—others, however, were spoken of as having reached a chronic stage. Many terminated in dementia. These very often showed stereotypies, verbigeration, impulsive excitements, mannerisms and other symptoms now held to be characteristic of dementia praecox. Melancholia was looked upon as including all emotional depressions with hallucinations and delusions as the prominent symptoms. The mental state was essentially one of sadness but with fear, agitation and anxiety appearing at times. There was, however, no attempt at any differentiation between psychomotor retardation with genuine depression and apathetic states or actual mental dulness. Mutism and resistiveness were common. A refusal of food was rather to be expected. Stuporous states with muscular rigidity frequently occurred. Various physical changes were described. Cyanosis of the extremities was emphasized, with loss of weight and a lowered temperature. Many of the cases were untidy in their habits. Brief initial attacks of excitement were mentioned as usually ushering in the disease. These depressions recovered, became chronic, lasting for years, or terminated in a partial or complete dementia. These were in substance the views of practically all of the earlier writers on insanity.
Sankey[274] in 1884 included in his idiopathic psychoses due to pathological conditions, general paresis and "ordinary insanity." "This is the disease which in its course presents such varying phenomena, and has thus given occasion for multiplying the names." Prominent in this group were the various forms of mania and melancholia and it undoubtedly included dementia praecox. "Like other diseases it may be artificially divided into separate stages, and this is useful for facilitating description, but such artificial divisions must not be looked upon as different species of disease." ... "Thus, a case in the primary attack commences by symptoms of melancholy; these may, when successfully treated, pass off, and the patient recover, or the melancholic stage may be aggravated, and the patient die in this stage;—the disease may exhibit symptoms of violence and become acutely maniacal. There is no ground on this account to say, that the patient has a new disease, any more than the appearance of an eruption in an eruptive disease would be the inauguration of a different kind of malady." Although obviously he had no idea as to the fundamental differences between manic-depressive insanity and dementia praecox, he unquestionably was one of the first to emphasize the fact that mania and melancholia were often definite stages of one disease process.
In 1896 Kraepelin described melancholia as essentially an involutional condition. Under the heading of periodic constitutional disorders he included mania, circular and depressive forms, the mania, melancholia, and circular insanity of other writers. Schüle[275] in 1886 described circular, periodical and alternating psychoses. In 1894 Ziehen[276] included in his classification under the heading of combined psychoses a "melancholisch-maniakalisches" form in addition to mania and melancholia, which he spoke of as affective psychoses.
It was not until 1899 that these conditions were clearly differentiated by Kraepelin[277] and the purely emotional and recoverable forms separated clinically from the deteriorative processes which he has associated with dementia praecox. The former he described as manic-depressive psychoses, which included mania, melancholia and a majority of the circular and alternating types previously described. This delimitation had a prognostic as well as an important symptomatic significance. The emotional excitements were characterized by an increased psychomotor activity, with a flight of ideas and distractibility, usually associated with a clear sensorium. Graver forms were, however, recognized, with a clouding of consciousness, and disorientation, occasionally terminating in stupor. Hallucinations and delusions when present were not prominent symptoms. The depressions were characterized by an emotional disturbance in the form of sadness with difficulty in thinking, associated with marked retardation in speech and a motor inhibition. More advanced stages showed clouding, disorientation, stuporous phases and hallucinations. He also recognized alternating or circular as well as mixed types. The prognostic importance of this clinical grouping was the tendency towards a complete recovery from the individual attack, with, however, an extreme probability later of a recurrence, the subsequent attacks assuming either form of the disease. As a rule Kraepelin found that the unfavorable types formerly included in the manias and melancholiac, together with the hebephrenia and katatonia of his fifth edition, presented the definite characteristics of the disease which he described as dementia praecox. His views have been modified from time to time. For instance, he at one time excluded the involutional and anxiety psychoses from his manic-depressive group. Later these were included. In his last edition he has described depressed and agitated forms of dementia praecox, which would strongly suggest that his lines of demarcation were not so clear as he believed them to be in 1899. Of the manic-depressive psychoses he says, "Manic depressive insanity as described in this chapter includes on the one hand the entire domain of the so-called periodic and circular insanities, on the other, simple mania, the larger part of the disease process described as melancholia and also a not inconsiderable number of cases of Amentia. Finally we include certain mild morbid emotional states, some periodical, some continuous, which heretofore have been looked upon either as introductory to more severe disturbances or as belonging, without being sharply circumscribed, to the domain of individual makeup. As years go by I have become more and more convinced that these all represent manifestations of one disease process." The following classification of manic-depressive psychoses was shown in Kraepelin's last edition (1913):—
Manic types:
Hypomania, Acute mania, Delusional and Delirious forms.
Depressive types:
Melancholia simplex, Melancholia gravis, Stupor, Paranoid, Phantastic and Delirious forms.
Mixed types:
Depressive mania.
Excited depressions.
Mania with poverty of thought.
Manic stupor.
Depression with flight of ideas.
Retarded mania.