Klaus' research interests are the computational capabilities of nervous systems. In single neurons, he is interested in neuronal excitability and dendritic signal integration. In networks, he is especially interested in "noise", synchronous oscillations, reverbaratory activity and concepts like liquid state machines.
His methods are theoretical and simulation-based. He aims for an approach which is informed by biology and inspired by dynamical systems; realistic without drowning in detail; empirically meaningful but conceptually groundbreaking at the same time. A serious side-interest of Klaus' is the biology of fishes, especially the marine family gobiidae (gobies). In 2011 he surveyed a marine region in the central Philippines for gobies down to a depth of 60 metres.