ON SCIENCE
A pioneer in artificial intelligence At the beginning of the 1980s, Teuvo Kohonen started thinking about how the human brain processes information—and came up with a significant advance in artificial intelligence studies: the self-organising map. Text Panu Räty
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rtificial intelligence applications have become part of everyday life also here in Finland. AI solutions are utilised in customer service, marketing, medical research and industrial processes alike. But each step forward in AI needs to be backed by extensive research. In addition to strong ongoing research, Finland’s advantage in the building of better artificial intelligences includes an exceptional history. One of the world’s key pioneers in AI research was none other than Helsinki University of Technology Professor Teuvo Kohonen (1934–2021). Represented as two-dimensional maps The January 1982 issue of Biological Cybernetics marked a turning point in the history of Finnish research. The scientific journal, which focuses on research in self-steering systems, published an article titled Self-Organized Formation of Topologically Correct Feature Maps by Professor Kohonen. Kohonen’s paper described a novel method for organising complex material into a twodimensional map in a way that groups sets containing similar features close to one another. The similarities and differences contained in the material are shown as distances between points on the map. 44 / AALTO UNIVERSITY MAGAZINE 30
Kohonen referred to his algorithm as a selforganising map (SOM) and his 11-page paper went on to become one of the most significant and cited Finnish research articles of its time. A former student of Kohonen and a member of his research group, Professor Emeritus of Computer Science Erkki Oja, describes the map as a great invention that opened up a key field of neural computation research. ‘Today, it serves as a typical example of research in unsupervised learning,’ Oja says. Inspired by the human brain When Kohonen penned his article for Biological Cybernetics, the research community was divided into two competing factions on the question of modelling thought processes computationally. Supporters of what is called classical symbolic AI believed that mental operations could be best modelled by using logical rules and relations created for the system. The neural computation camp, which Kohonen belonged to, held the view that the problem should be approached through collaborative action between computational units referred to as neurons. Oja says that Kohonen was inspired by how the human brain processed information and at first