Role of Area V6A in the Parieto-Frontal Network

The story of brain research is somehow the continuation of the ancient search for the magic stone or the life elixir. Trapped somewhere between laboratorial meticulousness, sentimental tradition, and regardless obsession, contemporary neuroscience demonstrates a very slow pace of advancing, and the only indisputable fact is that the questions at stake are of crucial importance for the improvement of life quality, intellectual satisfaction, and the discovery of real human limitations. To a young scientist, it seems very often that he has to choose between entering the chain of small discoveries leading to a great revelation after ten generations of hard work, or, on the other hand, starting to observe phenomena in a synthetical way, learning from all disciplines and directly speculating on. "cardinal questions." Unfortunately, the cruel scientific community does not encourage the latter choice, except in the case of neurophilosophers, which can never verify their ideas, and the so-called "authorities," who sometimes gained their reputation precisely from the coincidence of being at the end of a chain of "small" scientists and discoveries. One side of the medal suggests that one has only to bear practical sense for practical solutions always in mind. When one cannot any more explain the immediate practical implications of one's research, even if ephemeral, the sense of research is lost, the chain of fruitful discoveries is interrupted, the perspective of this kind of science is zero. "To get to know more about," as it is often the only argument of research papers, is only a sad deformation of science towards a hunt for grants and a comfortable status quo. Cognitive neuroscience can offer its contribution to two major fields: to technology, which can have profit from the models imitating neural networks and therefore facilitate human labour, and, par excellence, to medicine, where "practical sense" means application in therapeutic procedures. One is not obliged to test his findings directly or to convey them to industry or clinicians: it suffices if one knows in each moment what is the place of his work in the "chain" and what is the next step he (or somebody else) has to commit in order to reach that final "practical" scope. Studying one particular area of the brain-the way we have chosen-means to connect very specific disorders to very specific sites in order to become able to predict the outcome of human brain damage and to organise the adequate rehabilitation of debilitated skills. In our case, the chosen areas are located in the posterior superior parietal cortex and the defects observed primarily consider reaching, grasping, and orientation detection. Since, as yet, no efficient way of regenerating cortical tissue has been discovered, the only hope for regaining deteriorated functions is empirical rehabilitation, probably based on different manners of compensatory activities. In our case, it would be interesting to test whether the rehabilitation of one lost ability (for instance, orientation detection) would positively influence also the other skills (grasping and reaching). This and other possibilities should be the landmarks of the "chain" we joined. Nevertheless, there is another side of the medal. It is hardly known in natural sciences, but implicitly accepted in "humanities" (i.e., the group of disciplines called so because they allow human spirit to develop in its natural dimensions). According to this approach, one does not live to produce materially, but to form himself, to find out solutions to the questions he is confronted with, to narcissisticly enjoy his increasing knowledge without feeling remorse, and to make use of this know ledge by speculating and bringing sense in this way to everything around him. This state of limitlessness, which is not given to be felt by everyone, is probably in our case what Semir Zeki (1993, p. X) calls the "great fun the study of the brain can be."