After completing his studies in art history and philosophy in Hamburg, Bruhn obtained his doctorate with a dissertation on the correspondence of the French painter Nicolas Poussin. In 2001, he was one of the co-founders of the network "ArtHist", which has developed into a worldwide used information service in art history. As director of the research center "Politische Ikonografie" at the Warburg-Haus in Hamburg, his research focused on the historical forms of political representation, on the basis of media-economic factors of visual communication, especially the importance of photo agencies. With this topic Bruhn was a scholarship holder of the Akademie Schloss Solitude in Stuttgart, whose board of trustees he belongs to today. After a stopover in Cottbus in 2005 he took over the Berlin department "The Technical Picture", which is dedicated to the analysis of scientific forms of visualization. Bruhn is also a member of the Cluster of Excellence "Image Knowledge Design" and its successor "Matters of Activity", which will be collaborating over 40 different disciplines over the next seven years. In the academic year 2016/17, Bruhn was Visiting professor for Art Research at Karlsruhe University of Arts and Design. Now back in Karlsruhe, he will be offering interdisciplinary events based on the unique integrative structure of the university and also contributing to cooperation with the scientific and cultural institutions of the city.