Ebook: The Anatomical Substrate for Telencephalic Function
Author: C. Leonardus Veenman Dagmar Crzan Helene Kern Michael Rickmann Petra Wahle Peter van Mier (auth.)
- Tags: Anatomy, Neurosciences
- Series: Advances in Anatomy Embryology and Cell Biology 117
- Year: 1989
- Publisher: Springer-Verlag Berlin Heidelberg
- Edition: 1
- Language: English
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The basic thesis for this study was that the telencephalon is needed to make decisions in new situations. Subsidary hypotheses were that the telencephalon consists of: (a) a sensorimotor system which generates motor activity from sensory input and (b) a selection system which makes choices from possible motor programs. It was postulated that the selection system should fulfil the following requirements: be accessible for past and present events, have the capacity to process this information in a nondetermined way with a possibility for ordering, and have access to motor-affecting systems (the sensorimotor system). The ability of the selection system to correlate information in a nonpredetermined way was considered most important. In short: The selection system should be able to associate any information in any combination, and have the capability for internal control of neuronal activity and external selection of motor programs (see Fig. IA. ) Xenopus laevis was chosen as a subject, since it has a relatively simple tel encephalon, with characteristics that it shares with "primitive" species of different vertebrate classes, and because it is easy to maintain as a laboratory animal. The main method used was the determination of connections with HRP. The pallium was in the focus of attention, since it was considered to be the core of the selection system. Immunohistochemistry was used as an additional parameter to compare Xenopus laevis forebrain with those of other vertebrates.
This study is based on the thesis that the purpose of the telencephalon is to enable an animal to make decisions in new situations. The authors propose a model for the performance of this function based on the combination of a selection system with a sensory-motor system. The elements of the model were studied in Xenopus laevis and subsequently compared with the organization of the elements in other vertebrates. This model explains the effects of forebrain lesions and experimental physiological data, and it is generally applicable. It provides a tool for understanding the brain as such as well as a framework to which other input/output functions can be attached.