The 'subjective reduction' interpretation of measurement in quantum physics proposes that the collapse of the wave-packet, associated with measurement, is due to the consciousness of human observers. A refined conceptual replication of an earlier experiment, designed and carried out to test this interpretation in the 1970s, is reported. Two improvements are introduced. First, the delay between pre-observation and final observation of the same quantum event is increased from a few microseconds in the original experiment to one second in this replication. (...) Second, rather than using the final observers' verbal response as the dependent variable, his early brain responses as measured by EEG are used. These early responses cover a period during which an observer is not yet conscious of an observed event. Our results support the 'subjective reduction' hypothesis insofar as significant differences in the brain responses of the final observer are found, depending on whether or not the pre-observer has been looking at the quantum event . Alternative 'normal' explanations are discussed and rejected. It is concluded that the present results do justify further research along these lines. (shrink)

Methods in experimental science assume objective facts, and those effects are generally independent of the observer or experimenter. This objectivity assumption is not warranted in the field of human studies. Results of psychological experiments tend to be dependent on among other things the expectations of the experimenter. The experimenter effect togther with the replication crisis in social psychology are major issues in experimental parapsychology. We use Houtkooper's Hierarchical Observational Theory to look at a model for dealing with this issue, and (...) conclude that multiple-experimenter projects might be able to sort out experimenter effects from intrinisic effects. Keywords: experimenter effect; replication crisis; psi; parapsychology. (shrink)

Two experiments involving an international collaboration of experimenters sought to replicate and extend a previously published psi experiment on precognition by Daryl Bem that has been the focus of extensive research. The experiment reverses the usual cause–effect sequence of a standard psychology experiment using priming and reaction times. The preregistered confirmatory hypothesis is that response times to incongruent stimuli will be longer than response times to congruent stimuli even though the prime has not yet appeared when the participant records their (...) judgments. The confirmatory hypothesis for Experiment 1 was not supported. Exploratory analyses indicated that those participants who completed the English-language version rather than a translation showed a significant effect, as was the case in the original study; no significant departure from chance was found in data involving non-English translations. Experiment 2 sought to enhance the predicted effect by having each participant read either a pro-psi or an anti-psi statement at the beginning of the experiment to test the pre-recorded hypothesis that a pro-psi statement would produce a larger effect than an anti-psi statement. The results did not support the primary psi hypothesis and there was no effect in the English-language sample. However, there was mixed support for the effect of the psi statement on performance; those participants who received the pro-psi statement had a greater psi score than those who received the anti-psi statement. As in the original experiment, neither the experimenters’ nor participants’ beliefs were significantly associated with the dependent measure. In sum, the pre-registered confirmatory hypotheses were not supported. The importance of the personality variable Sensation Seeking, a component of extraversion, as a correlate of psi performance is discussed as are the challenges and implications for international collaborations and replication in controversial science. Keywords: priming; expectancy effect; retrocausation; consciousness; sociology; precognition; psi; replication Two experiments involving an international collaboration of experimenters sought to replicate and extend a previously published psi experiment on precognition by Daryl Bem that has been the focus of extensive research. The experiment reverses the usual cause-effect sequence of a standard psychology experiment using priming and reaction times. The preregistered confirmatory hypothesis is that response times to incongruent stimuli will be longer than response times to congruent stimuli even though the prime has not yet appeared when the participant records his or her judgments. The confirmatory hypothesis for Study 1 was not supported. Exploratory analyses indicated that those participants who completed the English-language version rather than a translation showed a significant effect, as was the case in the original study; no significant departure from chance was found in data involving non-English translations. Study 2 sought to enhance the predicted effect by having each participant read either a pro-psi or an anti-psi statement at the beginning of the experiment to test the pre-recorded hypothesis that a pro-psi statement would produce a larger effect than an anti-psi statement. The results did not support the primary psi hypothesis and there was no observed association between belief and experience of ESP and psi outcome. However, there was mixed support for the effect of the psi statement on performance; those participants who received the pro-psi statement had a greater psi score than those who received anti-psi statement. As in the original experiment, neither the experimenters’ nor participants’ beliefs or expectations were significantly correlated with the dependent measure. In sum, the pre-registered confirmatory hypotheses were not supported. The importance of the personality variable Sensation Seeking, a component of extraversion, as a correlate of psi performance is discussed as are the challenges and implications for international collaborations and replication in controversial science. (shrink)