[Pick's disease. A special type of pathological aging of the brain].

Pick's disease (circumscribed lobar atrophy of the brain) in its typical form, is a so-called presenile type of dementia, i.e. a cerebral disease which begins in the sixth decade of life, and leads to a progressive loss of intellectual capacity traits. Neuropathologically, Pick's disease is characterised by severe focal atrophy of the cerebral cortex, mainly of basal parts of the temporal and frontal lobe. In the long run, all the nerve cells of the affected areas and their processes are destroyed. This also involves the subcortical white matter (loss of nerve fibres and cicatrisation). Concomitant atrophies of other parts of the brain are frequent. The article reports on the results of the clinico-neuropathological examination of 30 cases of Pick's disease basing on the author's own observations. Special emphasis is placed on "neuronal atrophising dystrophy" of cortical systems as a characteristic change caused by Pick's disease; this phenomenon is interpreted as an endogenous disturbance of the neuronal structural metabolism. This process is, as a matter of principle, identical with the physiological "atrophising dystrophy" which represents part of cerebral aging. There are also pathogenetical parallels to orthological neuronal reactions to damaging of the axis cylinder processes. Pick's disease is characterised by the pathological extent and type of manifestation of "neuronal atrophising dystrophy". This pathological distortion of physiological processes is probably due to a specifically genetic and sometimes hereditary constellation. Finally, the article discusses the functional neuropathology or neuropsychology of Pick's disease. The importance of the basal temporofrontal cortex for the quality and preservation of human personality is emphasised; the changes of the high-class performances of the human brain, as caused by Pick's disease, are interpreted. Referring to the peculiarities of Pick's disease compared with normal cerebral aging, particular attention is drawn to the concept of "disease" and the definition of senile cerebral aging.