Heinrich Päs (Technische Universität Dortmund) A minimal approach to the measurement problem and the quantum-to-classical transition assumes a universally valid quantum formalism, i.e. unitary time evolution governed by a Schrödinger-type equation. As had been pointed out long ago, in this view the measurement process can be described by decoherence which results in a “Many-Worlds” or “Many-Minds” scenario according to Everett and Zeh. A silent assumption for decoherence to proceed is however, that there exists incomplete information about the environment our object system gets entangled with in the measurement process. This paper addresses the question where this information is traced out and – by adopting recent approaches to model consciousness in neuroscience – argues that a rigorous interpretation results in a modern perspective on the von-Neumann-Wigner interpretation – namely that the information that is or is not available in the consciousness of the observer is crucial for the definition of the environment. As such the quantum-to-classical transition while being difficult or impossible to probe in physics may become testable in psychology. Full text