Gregor[258] in 1907 made a careful analysis of seventy-two cases. He classified these in seven groups: 1. Neurasthenia; 2. Acute stuporous dementia; 3. Amentia (acute confusional insanity); 4. Acute delirium; 5. Katatonia; 6. Anxiety psychoses; and 7. Manic-depressive insanity. The neurasthenic cases (9.72 per cent) exhibited headache, pain in the gastric region, vertigo, paresthesia and lassitude, with a sense of unrest and anxiety as well as ill-defined apprehensions. There was a sense of mental incapacity and feeling of illness, together with a mild depression and hypochondriacal tendencies. The cases diagnosed as acute dementia (13.88 per cent) were of the same general type but with more advanced symptoms. These showed a decided stupor, tending to remission, deep mental depression, a sense of insufficiency and "peculiar subjective troubles." The tendency to suicide was prominent and caused this group to be called melancholia by some. Many cases showed the gradual development of an affectless stupor. Catatonic symptoms and stereotypies occasionally occurred. Memory disturbances were well marked in this form. The psychoses disappeared invariably with the symptoms of the pellagra. The Amentia group (44.44 per cent) included long-continued cases with remission and intermissions. Terrifying hallucinations and violent motor excitement appeared frequently, followed by a stupor which was sometimes interrupted by delirium. Hallucinations were usually present and some had dream states. These cases often terminate unfavorably. Acute delirium constituted 2.7 per cent of the seventy-two cases, and katatonia occurred in 13.8 per cent. These cases passed rapidly into dementia. Anxiety psychoses (4.16 per cent) were diagnosed in a few instances, but were complicated by occasional stupors. Two and seven-tenths per cent of the cases were classified as manic-depressive insanity. Mobley, according to Babcock, found the following types represented at the Georgia State Sanitarium:—1. Acute intoxication psychosis, with psychomotor suspension; 2. Infective exhaustive psychosis, with psychomotor retardation or excitation; 3. Symptomatic melancholia with psychomotor retardation; and 4. Manic-depressive psychoses. Singer[259] in 1915 suggested the following classification of the psychoses associated with pellagra:— 1. Disorders directly due to the pellagra toxin: (a) Symptomatic depression; (b) Delirious pictures. 2. Disorders based on peculiarities in personal make-up, the attack of "insanity" being precipitated by pellagra; (a) Manic-depressive disorders; (b) Hysteria; (c) Psychasthenia; (d) Dementia praecox; (e) Paranoic developments; and 3. Disorders due to definite brain changes with pellagra merely as a complication: (a) Arteriosclerotic dementia; (b) Senile dementia; (c) Presenile psychoses; (d) General paralysis of the insane.