This kind of experiments originated in the psychokinesis (PK) investigations of parapsychology, as carried out in the institute of Professor Joseph B. Rhine, the founder of experimental PSI research, at Duke University [Bösch, Steinkamp & Boller 2006]. Beloff und Evans  have been the first researchers to replace the usual experiments with dice with the radioactive decay as the source of genuine random signals for the mental influence. A few years later experiments were developed where the output of a radioactive source was transformed in bits (ones and zeros) that could be stored in a computer; the corresponding devices were called random number generators (RNG, later random event generators, REG). Later RNG’s were generally used based either on avalanche generators (Zener generators) or thermal noise as a source for random events. In those early RNG researches the genuine random character of the noise was considered crucial, although the good technical manageability and the much easier control over the experimental conditions compared to the dice experiments were the most important arguments for the use of RNG’s.
Another reason for the use of the RNG’s was that researchers in the 1970’s began PSI phenomena to model in the framework of quantum physical concepts. As a consequence, PK experiments with dice were almost completely replaced with by experiments with RNG’s. This direction of the experimental investigation of the mental influence of random material processes mainly has been carried on in the 1970’s by the American physicist of German descent, Helmut Schmidt (1928-2011), and later in the 1980’s by the PEAR Lab at the University of Princeton. Schmidt worked with electronic random event generators which were based on the radioactive decay process. Schmidt has been research director of the well known Rhine Research Center Institute for Parapsychology from 1969 and continued his researches later in the Mind Science Foundation in San Antonio, California.
These investigations were carried on in the Princeton Engineering Anomalies Research (PEAR) Laboratory at Princeton University in Princeton, New Jersey, USA, founded by Robert G. Jahn and Brenda J. Dunne in 1979. Jahn was Professor for Aerospace Sciences and Dean of School of Engineering and Applied Science at this renowned university and founded the PEAR Lab together with the psychologist Brenda J. Dunne, with the goal of “the investigation of the potential vulnerability of technical devices and information processing systems for the anomalous influence by the consciousness of their operators”. Initially, the possible mental influence of mechanical random processes like the fall of balls through arrays of metal pins were investigated, later however portable REG’s were used in order to test the anomalous influence of group events “with a high degree of subjective resonance between the participants” on the output of electronic noise generators. The results of the high number of experiments carried out by Jahn, Dunne and Nelson and their collaborators in the course of a quarter of a century at the PEAR Lab, have without any doubt shown that the human mind is able to influence physical random processes, and have therefore led to a significant breakthrough in parapsychology [Nelson et al. 1996, 1998; Radin et al. 1996; Bierman 1996; Radin 1996; Special Issue of Explore 2007].
After more than 26 years of research activities the PEAR Lab was closed in 2007. Its work was, with a slightly changed objective, carried on in the International Consciousness Research Laboratory (ICRL) in Princeton and in the “Global Consciousness Project” by Roger Nelson.
Another significant type of experiments concerning random events derives from the work the Russian biophysicist Simon E. Shnoll, professor at the Lomonossov State University at Moscow and at the Institute of Biophysics of the Academy of Sciences in Pushchino. In the 90’s, he began first to publish the results of experiments in which he had investigated during more than 40 years random processes of all kinds with his collaborators, such as the radioactive decay or the noise in electronic devices [Shnoll 1999]. Certain statistical analysis methods uncovered strange concealed patterns whose origin has remained enigmatic. Measurement curves from measurements done at certain locations showed during a certain time a similar form, which was after a certain time replaced by another form. This curve forms recurred in cyclical form in periods of 24 hours, 27 days, and ca. 365 days. The curve forms displayed also a geographical dependency, as processes at locations of the same geographical latitude showed always the same curve forms. The patterns were different according to the cardinal direction and changed with the rotation of the earth.