Audio signal processing to investigate alleged paranormal phenomena in mediumistic séances

Probably many people have heard stories about spiritualism, séances in entire darkness, and mediumship claiming to establish contact to deceased persons. Much less known is that this is not just a historic or fictional matter, but today it is still possible to experience such séances, with some mediums even holding séances open to the public. There, various phenomena can be witnessed, which are a serious challenge for the rational mind. This article does not want to engage in the discussion between skeptical mainstream science and convinced psi-researchers about the authenticity of these phenomena, but it rather follows an undogmatic, curiositydriven approach: Let us see what kind of data audio measurements can provide in this field! Ideally, there is something into it, both for psi-research as well as for audio signal processing.