Much of the work of the era was summarized by Ariëns Kappers, Huber, and Crosby (1936).Ĭoncurrently, others studied comparative behavior effectively without a simultaneous study of the structure of the nervous system, but they did not overlook the possibility of relating behavior to the nervous system. Herrick worked in an era of considerable interest in comparative neuroanatomy. Coghill (1929) spent much of his life in the study of the development of the nervous system of the salamander, in conjunction with a study of the development of behavior. Herrick (1948) concentrated on the connections found in amphibian nervous systems, relating his information to the findings of workers who used other forms and interpreting the possible significance of the described connections. Coghill, continued in the tradition of the elder Herrick after his death. His original vision was that the study of comparative neuroanatomy could be integrated with the study of comparative behavior. Herrick was moved by such considerations when he founded the Journal of Comparative Neurology in 1891. In practice, it is reasonable to suggest that comparative neurology and comparative behavior have information to offer which is relevant for evolutionary theory and, conversely, that evolutionary perspective provides a framework for making sense out of comparative material. Comparative behavior provides similar encouraging parallels. Patterns in the brain are found which are common to these and different species suggesting parallels with common ancestry. What leads us to believe that it is possible to investigate the evolution of the brain and its relation to behavior?Īn answer lies in the encouragement investigators obtain from examining the brains of those contemporary organisms which have close links with their fossil ancestors. In our lifetimes, we experience but a very brief interlude in the long evolutionary process. We cannot study behavior in fossils or the internal structure of the brain of organisms long dead. The study of the evolution of the brain and behavior is a paradox. IV ELECTROENCEPHALOGRAPHY Donald LindsleyīIBLIOGRAPHY I Evolutionary and Behavioral Aspects of The Brain III BRAIN STIMULATION William Hodos and Joseph V. II STRUCTURE AND FUNCTION OF THE BRAIN Frederick A. It cannot simply be a matter of the absolute amounts of pigment present in any one cell type, but rather might be that there is a critical concentration of such material in the cytoplasm.I Evolutionary and Behavioral Aspects of The Brain Walter Riss It seems, therefore, that, if there is a causal relationship between lipofuscin accumulation and reductions in RNA and nucleolar volume, it is rather obscure. Olivary cells which contain most pigment show a different pattern of change with losses of RNA and nucleolar volume of about 60%. Both the RNA content and nucleolar volume of dentate, olivary and hippocampal cells decrease, with advancing age, in a similar way in all of these 3 cell types, despite the widely differing extents of pigment accumulation, with losses of RNA and nucleolar volume at 90 years of age of 15 and 30% respectively. All 4 cell types accumulate lipofuscin in a linear manner throughout life, but to markedly differing extents. The cytoplasmic RNA content, nucleolar volume and lipofuscin content of nerve cells of the inferior olivary and dentate nuclei, Purkinje cells and pyramidal cells of the hippocampus has been measured in 82 persons of age range 2-91 years, who were free from overt neurological disease at the time of death.
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