OPINION ARTICLE published: 23 December 2013 HUMAN NEUROSCIENCE doi: 10.3389/fnhum.2013.00893 Anomalous experiences, psi and functional neuroimaging

David J. Acunzo 1, Renaud Evrard 2 and Thomas Rabeyron 3*

1 School of Informatics, Institute for Adaptive and Neural Computation, University of Edinburgh, UK 2 SULISOM, Psychology Department, University of Strasbourg, Strasbourg, France 3 LPPL, Psychology Department, University of Nantes, Nantes, France *Correspondence: [email protected]

Edited by: Etzel Cardeña, University of Lund, Sweden Reviewed by: John A. Palmer, Rhine Research Center, USA

Keywords: anomalous experiences, telepathy, precognition, distant intentionality, fMRI, psi, methodology

Over the past decade, there has been about anomalous experiences can stim- improvement of the research in this field. increasing scientific interest in anoma- ulate cutting-edge discussions on scien- These methodological weaknesses can be lous experiences. These can be defined tific methodology. This heuristic value grouped into four categories: as “uncommon experience[s] [...] that, of anomalous experiences has a history although [they] may be experienced by even in the infancy of cognitive neuro- 1. Counter-balancing across participants a significant number of persons [...], science with the German neurologist Hans is routinely used in experimental psy- [are] believed to deviate from ordinary Berger, inventor of electroencephalogra- chology and cognitive sciences to avoid experience or from the usually accepted phy and the first person to describe differ- systematic biases due to experimental explanation of reality according to Western ent brain waves, having previously had a conditions specific to one or several mainstream science” (Cardeñaetal., telepathic experience with his sister which participants. In Venkatasubramanian 2014). This scientific interest has led made him obsessed by the idea of how et al. (2008), the receiver and the sender to important contributions toward the his mind could have carried such a signal were presented green and red-colored understanding of several aspects of these (Berger, 1940). stars to indicate the onset of telepa- experiences (Brugger and Mohr, 2008). More recently, attempts to test the psi thy and control trials, respectively. One of the most controversial hypotheses hypothesis and find its neural correlates It is therefore not possible to know associated with anomalous experiences is have been carried out using functional whether the difference in brain activ- the psi hypothesis, which states that anoma- neuroimaging. The rationale behind these itybetweenthetwoconditionsisdue lous experiences sometimes imply forms experiments is that if psi-related processes to the nature of the trial (telepathy vs. of interactions falling outside currently are indeed present in the brain, even control) or to the difference in the color known biological and physical mecha- unconsciously, they should be observable of the stimulus indicating trial onset. nisms (Bem and Honorton, 1994). Thus, using functional neuroimaging. An exam- To disentangle this potential confound, far, small but persistent effects are fre- ple of such a study would be to test the reverse cue association has to be quently reported in experiments testing whether the brain activity of Participant given for half of the trials—or half the psi hypothesis (Radin, 2006), while A would be influenced when Participant of the participants, if their number is no consensus has been reached concerning B, situated in another isolated room, sufficient. their explanation (Alcock et al., 2003). intends to send information to or sim- 2. Trial order randomization prevents Research testing the psi hypothesis ply concentrate on Participant A. Various biases that could be caused by the par- has occasionally generated a great deal types of hypothetical phenomena have ticular order of the trial conditions. of interest and controversy. The most already been examined, including forms of Such biases can be caused by partici- recent example is Bem’s series of precog- telepathy (Standish et al., 2003; Richards pants detecting a certain pattern (e.g., nition experiments (Bem, 2011), which et al., 2005; Moulton and Kosslyn, 2008; repetitions or alternations), leading to triggered important methodological ques- Venkatasubramanian et al., 2008), distant expectations and thus detectable neural tionings on the validity of the frequen- intentionality (Achterberg et al., 2005), signatures that could bias the results. tist approach (Miller, 2011; Rouder and and precognition (Bierman and Scholte, Habituation, leading to different brain Morey, 2011; Wagenmakers et al., 2011), 2002; Moulton and Kosslyn, 2008). All activity between the beginning and widely used in experimental sciences. these six studies but one (Moulton and the end of the experiment may also Bem’s paper was followed by an attempt Kosslyn, 2008) reported results consistent bias the results. To counter-balance the of replication (Ritchie et al., 2012a), which with the psi hypothesis. potential biases produced by a particu- resulted in reflections on the difficulty in Unfortunately, several of these stud- lar sequence—even if it was generated publishing direct replications in psychol- ies suffer from methodological weaknesses randomly—each participant should be ogy (Ritchie et al., 2012b). This debate, that could account for the reported effects. given a distinct series of randomly- still ongoing, has shown how research Listing these flaws may contribute to the ordered trials. Unfortunately, proper

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randomization was not met in four of results have a low probability to reflect ACKNOWLEDGMENTS the six studies: In Venkatasubramanian a true effect (see e.g., Button et al., We thank Mark van Rossum for help- et al. (2008) no randomization was 2013). Furthermore, with too few par- ful comments on an earlier version of used at all, while in Standish et al. ticipants, proper counter-balancing is the manuscript and Jocelyn Timperley for (2003) and Richards et al. (2005) the difficult and the risk of confounds is reviewing the final versions. duration of the trials was random- greater. ized, but not their order. Moreover, in the Venkatasubramanian study, the Two studies (Bierman and Scholte, 2002; REFERENCES Achterberg, J., Cooke, K., Richards, T. L., Standish, L. target picture was freely chosen and Moulton and Kosslyn, 2008), however, J., Kozak, L., and Lake, J. (2005). Evidence for cor- drawn with a pen by one investigator appear methodologically sound. 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