dzou writes: "David Rumelhart, a pioneer in building computer models of cognition and behavior, has died at the age of 68. Rumelhart conducted early research on artificial neural networks and helped develop the idea that cognition can be modeled through the interaction of many neuron-like units. In the 1980s, he was instrumental in developing neural networks that could learn to process information. At the time, although researchers understood how to train networks to solve linearly separable problems (like an AND gate), those networks could not solve linearly inseparable problems (like XOR), which would be crucial for modeling human cognitive processes. Rumelhart and his colleagues demonstrated that networks that solve these types of problems can be trained using the backpropagation learning algorithm. In turn, this has led to breakthroughs in areas like speech recognition and image processing, as well as models of human speech perception, language processing, vision, and higher-level cognition. Rumelhart suffered from Pick's disease in the last years of his life. An annual award in cognitive science, the David E. Rumelhart Prize, is given in his honor by the Glushko-Samuelson Foundation."