Italian psychologist and psychical researcher (1862–1943), author of number of books analysing psi phenomena. 

American parapsychologist and author (1942-2012), pioneer of the experimental study of distant mental influence on living systems (DMILS).

American philosopher and parapsychologist, notable for his PK research and for commentary on trance mediumship and survival evidence, in particular his defence of the 'living agent' (super-psi) hypothesis. 

British writer and stage performer (1823–1899), best known for her advocacy of the burgeoning Spiritualism movement in the late nineteenth century.

American parapsychologist who has specialized in cognitive aspects of ESP and its evolutionary development. His 1991 book Parapsychology: The Controversial Science is a classic introduction to the subject. 

Swedish researcher who has studied anomalous connections between twins. He is author of Conscious Connections (2010), a book linking parapsychology with holistic biology.

Cédric Cannard is a French researcher based at the Institute of Noetic Sciences in California, working on altered states of consciousness and psi phenomena.

Dani Caputi is an American atomospheric science researcher who has investigated consciousness-related effects in micro-meteorological processes.

Mexican-born psychologist based at Sweden's Lund University, a leading psi advocate in mainstream media, with research interests in conciousness, dissociation and altered states.

British psychical researcher (1892-1947) who pioneered the use of quantitative methods based on word association tests in the investigation of mediumship.