Much of the Koestler Unit's research program centered on the ganzfeld procedure, an experimental design using mild sensory deprivation intended to test telepathy under conditions that reduce ordinary sensory cues, which had become the most actively debated method in the field after psychologist Charles Honorton and skeptic Ray Hyman published a joint statistical analysis of earlier ganzfeld studies in 1986.
Unit researchers Julie Milton and Richard Wiseman published a widely cited 1999 meta-analysis of ganzfeld studies conducted after that joint statement, finding that the apparent psi effect had not been replicated across the newer body of experiments, a result that became a central piece of evidence for skeptics even though it was produced by researchers working inside a parapsychology unit rather than by outside critics.
The finding illustrates the Unit's general approach under Morris, which emphasized methodological self scrutiny and was often more critical of weak evidence than outside observers expected from a dedicated parapsychology laboratory. Morris served as Koestler Professor until his death in August 2004, after which the university continued to support parapsychological teaching and research, including the Koestler Parapsychology Library, within its School of Philosophy, Psychology and Language Sciences, maintaining Edinburgh's position as the principal United Kingdom academic center for the field even as the endowed chair itself was not immediately refilled.