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Background and purpose: Mediumship is the ostensible phenomenon of human-mediated communication between deceased and living persons. In this paper, we perform a meta-analysis of all available modern experimental evidence up to December 2019 investigating the accuracy of apparently anomalous information provided by mediums about deceased individuals.
Publication bias and questionable research practices in primary research can lead to badly overestimated effects in meta-analysis. Methodologists have proposed a variety of statistical approaches to correct for such overestimation. However, it is not clear which methods work best for data typically seen in psychology. Here, we present a comprehensive simulation study in which we examined how some of the most promising meta-analytic methods perform on data that might realistically be produced by research in psychology. We simulated several levels of questionable research practices, publication bias, and heterogeneity, and used study sample sizes empirically derived from the literature. Our results clearly indicated that no single meta-analytic method consistently outperformed all the others. Therefore, we recommend that meta-analysts in psychology focus on sensitivity analyses—that is, report on a variety of methods, consider the conditions under which these methods fail (as indicated by simulation studies such as ours), and then report how conclusions might change depending on which conditions are most plausible. Moreover, given the dependence of meta-analytic methods on untestable assumptions, we strongly recommend that researchers in psychology continue their efforts to improve the primary literature and conduct large-scale, preregistered replications. We provide detailed results and simulation code at https://osf.io/rf3ys and interactive figures at http://www.shinyapps.org/apps/metaExplorer/.
The recent ‘replication crisis’ in psychology has focused attention on ways of increasing methodological rigor within the behavioral sciences. Part of this work has involved promoting ‘Registered Reports’, wherein journals peer review papers prior to data collection and publication. Although this approach is usually seen as a relatively recent development, we note that a prototype of this publishing model was initiated in the mid-1970s by parapsychologist Martin Johnson in the European Journal of Parapsychology (EJP) . A retrospective and observational comparison of Registered and non-Registered Reports published in the EJP during a seventeen-year period provides circumstantial evidence to suggest that the approach helped to reduce questionable research practices. This paper aims both to bring Johnson’s pioneering work to a wider audience, and to investigate the positive role that Registered Reports may play in helping to promote higher methodological and statistical standards.
The random‐effects model, applied in most meta‐analyses nowadays, typically assumes normality of the distribution of the effect parameters. The purpose of this study was to examine the performance of various random‐effects methods (standard method, Hartung´s method, profile likelihood method and bootstrapping) for computing an average effect size estimate and a confidence interval (CI) around it, when the normality assumption is not met. For comparison purposes, we also included the fixed‐effect model. We manipulated a wide range of conditions, including conditions with some degree of departure from the normality assumption, using Monte Carlo simulation. In order to simulate realistic scenarios, we chose the manipulated conditions from a systematic review of meta‐analyses on the effectiveness of psychological treatments. We compared the performance of the different methods in terms of bias and mean squared error of the average effect estimators, empirical coverage probability and width of the CIs, and variability of the standard errors. Our results suggest that random‐effects methods are largely robust to departures from normality, with Hartung's profile likelihood methods yielding the best performance under suboptimal conditions.
Mediums are individuals who report experiencing regular communication with the deceased; the phenomenon of mediumship has been reported in cultures all over the world since time immemorial. The current study examined similarities and differences in the reported experiences of secular American mediums (those not associated with any formal religious organization) during mediumship readings involving communication with the deceased and during psychic readings for/about the living. Participant responses to two counter-balanced, open-ended online survey items were quantitatively analyzed using Linguistic Inquiry and Word Count (LIWC) text analysis software and qualitatively analyzed using a content analysis methodology. Participants included 113 self-identified mediums and 14 Windbridge Certified Research Mediums; over 90% were white females; their average age was 54.2 ± 9.6 years; 97% reported being able to distinguish between mediumistic and psychic experiences; and 122 provided complete survey responses. Statistically significant differences between descriptions of mediumistic and psychic experiences were seen regarding the proportion of words included in the LIWC categories of: social processes (11.76% ± 5.8% vs. 9.93% ± 5.64%, p=0.004); perceptual processes (6.63% ± 4.31% vs. 4.81% ± 3.81%, p<0.001); ingestion (0.23% ± 0.57% vs. 0.05% ± 0.20%, p<0.001); past-focused time orientation (3.09% ± 3.23% vs. 2.06% ± 3.19%, p=0.001); religion (0.90% ± 0.11% vs. 0.34% ± 0.09%, p<0.001); and insight (5.06% ± 2.97% vs. 6.48% ± 4.30%, p=0.002). The proportion of words describing positive and negative emotions, present-focused and future-focused time orientation, health, and money were not different. Qualitative content analysis found three overarching, summative themes regarding mediumistic communication: preparation, communication triangulated, and experience of the communication. Four overarching, summative themes emerged from the text regarding psychic readings for the living: establishing the connection, experiencing the connection, content of the reading, and psychic information flowing from various sources. Perhaps most interesting is the finding that experiences of psychic connections during readings for the living included “non-specific discarnates” as a source of information; this strongly calls into question theoretical frameworks that posit separating mediums’ experiences into categories that do and do not involve communication with the deceased as well as the continued use of terminology reflecting such a separation.
This study was supported by a research bursary (#372/14) from the Bial Foundation.
Numerous mediumship studies (e.g., Beischel & Schwartz 2007, Kelly & Arcangel 2011, Rock, Beischel, Boccuzzi, & Biuso 2014) have reported statistically significant results, thus suggesting that various contemporary mediums are able to demonstrate anomalous information reception (AIR) under laboratory conditions. Importantly, however, such studies are unable to address the source of mediums' AIR. Indeed, the source-of-psi problem (survival-psi and living agent psi [LAP] being the most likely contenders) cannot be resolved using current methodologies (Beischel 2012). However, innovative mediumship-Testing techniques may produce results that indicate a convergence whereby sets of outcomes may evidentially favor one hypothesis over another (e.g., see Jamieson & Rock 2014 for a neurophenomenological approach). We present an innovative methodology focused on investigating whether mediums and well-rehearsed proxy-sitters, working under well-beyond double-blind conditions, create telepathic links that we refer to as dyad-Telepathy, thereby producing response sets that indicate the psi source is more likely to be dyad-Telepathy than a discarnate entity.
We describe a method of quantifying the effect of Questionable Research Practices (QRPs) on the results of meta-analyses. As an example we simulated a meta-analysis of a controversial telepathy protocol to assess the extent to which these experimental results could be explained by QRPs. Our simulations used the same numbers of studies and trials as the original meta-analysis and the frequencies with which various QRPs were applied in the simulated experiments were based on surveys of experimental psychologists. Results of both the meta-analysis and simulations were characterized by 4 metrics, two describing the trial and mean experiment hit rates (HR) of around 31%, where 25% is expected by chance, one the correlation between sample-size and hit-rate, and one the complete P-value distribution of the database. A genetic algorithm optimized the parameters describing the QRPs, and the fitness of the simulated meta-analysis was defined as the sum of the squares of Z-scores for the 4 metrics. Assuming no anomalous effect a good fit to the empirical meta-analysis was found only by using QRPs with unrealistic parameter-values. Restricting the parameter space to ranges observed in studies of QRP occurrence, under the untested assumption that parapsychologists use comparable QRPs, the fit to the published Ganzfeld meta-analysis with no anomalous effect was poor. We allowed for a real anomalous effect, be it unidentified QRPs or a paranormal effect, where the HR ranged from 25% (chance) to 31%. With an anomalous HR of 27% the fitness became F = 1.8 (p = 0.47 where F = 0 is a perfect fit). We conclude that the very significant probability cited by the Ganzfeld meta-analysis is likely inflated by QRPs, though results are still significant (p = 0.003) with QRPs. Our study demonstrates that quantitative simulations of QRPs can assess their impact. Since meta-analyses in general might be polluted by QRPs, this method has wide applicability outside the domain of experimental parapsychology.
Systematic reviews should build on a protocol that describes the rationale, hypothesis, and planned methods of the review; few reviews report whether a protocol exists. Detailed, well-described protocols can facilitate the understanding and appraisal of the review methods, as well as the detection of modifications to methods and selective reporting in completed reviews. We describe the development of a reporting guideline, the Preferred Reporting Items for Systematic reviews and Meta-Analyses for Protocols 2015 (PRISMA-P 2015). PRISMA-P consists of a 17-item checklist intended to facilitate the preparation and reporting of a robust protocol for the systematic review. Funders and those commissioning reviews might consider mandating the use of the checklist to facilitate the submission of relevant protocol information in funding applications. Similarly, peer reviewers and editors can use the guidance to gauge the completeness and transparency of a systematic review protocol submitted for publication in a journal or other medium.
There have been many attempts to provide evidential support for the notion that consciousness continues after death. One important line of investigation uses mediums—people who claim to act as conduits between the living and the dead. If one could produce evidence that some mediums can reliably acquire information about dead people that they never knew without relying on any possible normal source of information—evidence of " anomalous information reception " (AIR)—this would suggest the operation of some para-normal process. are unfortunately as flawed as they are numerous. Previous literature has reviewed common flaws in much current experimental mediumship research.
This paper presents a brief review of the debate between parapsychologists and skeptics regarding the issue of replication in experimental tests of extrasensory perception (ESP) using a sensory reduction technique known as ganzfeld. The review is followed by a basic assessment of 59 ganzfeld ESP studies reported in the period following the publication of a stringent set of methodological guidelines and recommendations by R. Hyman and C. Honorton in 1986. The assessment indicates that these 59 studies have a combined hit rate of approximately 30%, which is significantly above the chance expected hit rate of 25%. A comparison of the hit rates across four ganzfeld meta-analyses, as well as across fifteen laboratories, seems to further indicate replication of the ganzfeld ESP effect by a broad group of independent researchers.
Keywords: extrasensory perception (ESP)—ganzfeld—meta-analysis—psi—parapsychology
The examination of the accuracy and specificity of information reported by mediums addresses the existence of non-local information transfer.
This study was designed to replicate and extend a previous methodology achieving positive findings regarding the anomalous reception of information about deceased individuals by research mediums under experimental conditions that eliminate conventional explanations, including cold reading, rater bias, experimenter cueing, and fraud.
Mediumship readings were performed over the phone under blinded conditions in which mediums, raters, and experimenters were all blinded.
A total of 20 Windbridge Certified Research Mediums WCRMs participated in 86 readings.
Main outcome measures:
Accuracy and specificity were assessed through item scores, global reading scores, and forced-choice selections provided by blinded sitters.
(1) Comparisons between blinded target and decoy readings regarding the estimated percentage accuracy of reading items (n = 27, P = .05, d = 0.49), (2) comparisons regarding the calculated percentage accuracy of reading items (n = 31, P = .002, d = 0.75), (3) comparisons regarding hits vs. misses (n = 31, P < .0001 and P = .002 for different reading sections), (4) comparisons regarding global scores (n = 58, P = .001, d = 0.57), and (5) forced-choice reading selections between blinded target and decoy readings (n = 58, P = .01) successfully replicate and extend previous findings demonstrating the phenomenon of anomalous information reception (AIR), the reporting of accurate and specific information without prior knowledge, in the absence of sensory feedback, and without using deceptive means. Because the experimental conditions of this study eliminated normal, sensory sources for the information mediums report, a non-local source (however controversial) remains the most likely explanation for the accuracy and specificity of their statements.
During advanced meditative practices, unusual perceptions can arise including the sense of receiving information about unknown people who are deceased. As with meditation, this mental state of communication with the deceased involves calming mental chatter and becoming receptive to subtle feelings and sensations. Psychometric and brain electrophysiology data were collected from six individuals who had previously reported accurate information about deceased individuals under double-blind conditions. Each experimental participant performed two tasks with eyes closed. In the first task, the participant was given only the first name of a deceased person and asked 25 questions. After each question, the participant was asked to silently perceive information relevant to the question for 20 s and then respond verbally. Responses were transcribed and then scored for accuracy by individuals who knew the deceased persons. Of the four mediums whose accuracy could be evaluated, three scored significantly above chance (p < 0.03). The correlation between accuracy and brain activity during the 20 s of silent mediumship communication was significant in frontal theta for one participant (p < 0.01). In the second task, participants were asked to experience four mental states for 1 min each: (1) thinking about a known living person, (2) listening to a biography, (3) thinking about an imaginary person, and (4) interacting mentally with a known deceased person. Each mental state was repeated three times. Statistically significant differences at p < 0.01 after correction for multiple comparisons in electrocortical activity among the four conditions were obtained in all six participants, primarily in the gamma band (which might be due to muscular activity). These differences suggest that the impression of communicating with the deceased may be a distinct mental state distinct from ordinary thinking or imagination.
Mediums claim to be able to report accurate and specific information about the deceased loved ones (termed discarnates) of living people (termed sitters) even without any prior knowledge about the sitters or the discarnates and in the complete absence of any sensory feedback. Despite recent proof-focused experimental research investigating this phenomenon (e.g., Beischel & Schwartz, 2007), no published studies have attempted to quantify the phenomenological effects of discarnate readings. The aim of the present study was, thus, to investigate experimentally the phenomenological differences that arose psychologically in accordance with the demands of a discarnate reading task versus a control task. Seven mediums were administered counter-balanced sequences of a discarnate reading and control condition. The discarnate reading condition consisted of a phone reading including questions about a discarnate where only a blinded medium and a blinded experimenter were on the phone. The control condition consisted of a phone conversation between the medium and the same experimenter in which the medium was asked similar questions regarding a living person s/he (i.e., the medium) knew. Mediums' phenomenology during each condition was retrospectively assessed using the Phenomenology of Consciousness Inventory (PCI). Phenomenology associated with the discarnate reading condition appeared to be significantly different from phenomenology associated with the control condition. Future research might use the PCI to address whether the phenomenology reported by mediums during discarnate readings is quantitatively different from their experiences during psychic telepathy readings for the living.
Over a century of mediumship research concludes that skilled mediums are able to report accurate and specific information about the deceased loved ones (termed discarnates) of living people (termed sitters) during anomalous information reception (AIR); that is, without any prior knowledge about the discarnates or sitters, in the absence of sensory feedback, and without using deceptive means. However, this historical body of proof-focused research does not directly address which parapsychological mechanisms are involved in AIR by mediums. The data, in and of themselves, support multiple hypotheses including the super-psi and psychic reservoir (collectively "psi") models as well as the survival of consciousness hypothesis (or simply "survival" ). However, by restricting research to proof-focused studies, investigators neglect important phenomenological mediumship processes underlying AIR and how those processes might address the survival hypothesis. This processfocused investigation of mediums' experiences may lead to a better understanding of the source of the information mediums report during AIR. This paper briefly summarizes the results from recent process-focused studies of modern-day, American mental mediums' experiences during ostensible communication with discarnates. We also suggest areas for future process-focused mediumship studies to more fully address the question at the root of mediumship research: Is there life after death?
According to the survivalist interpretation of mediumship, the existence of discarnate persons provides the best explanation for the data associ-ated with physical and mental mediumship. Others—advocates of what is often called the "super-psi hypothesis"—maintain that the data of mediumship may be at least equally explained in terms of living agent psi (ESP and psychokinesis). Many defenders of the survivalist interpretation of mediumship attempt to defl ate the alleged explanatory virtues of the super-psi hypothesis by arguing that the hypothesis is unfalsifi able and lacks independent evidential support. My central contention in this paper is that these frequently encountered survivalist criticisms of the super-psi hypothesis are ultimately self-defeating to the case for survival from mediumship. To show this I fi rst argue in some detail that the survivalist interpretation of mediumship is committed to a kind or degree of psi that is indistinguishable from what is required by the super-psi hypothesis. From this vantage point it can be shown that any attempt to impugn the explanatory virtues of the super-psi hypothesis on account of the kind or degree of psi it requires undercuts the argument for survival itself.
The metafor package provides functions for conducting meta-analyses in R. The package includes functions for fitting the meta-analytic fixed- and random-effects models and allows for the inclusion of moderators variables (study-level covariates) in these models. Meta-regression analyses with continuous and categorical moderators can be conducted in this way. Functions for the Mantel-Haenszel and Peto's one-step method for meta-analyses of 2 x 2 table data are also available. Finally, the package provides various plot functions (for example, for forest, funnel, and radial plots) and functions for assessing the model fit, for obtaining case diagnostics, and for tests of publication bias.
Parapsychology, the laboratory study of psychic phenomena, has had its history interwoven, with that of statistics. Many of the controversies in parapsychology have focused on statistical issues, and statistical models have played an integral role in the experimental work. Recently, parapsychologists have been using meta-analysis as a tool for synthesizing large bodies of work. This paper presents an overview of the use of statistics in parapsychology and offers a summary of the meta-analyses that have been conducted. It begins with some anecdotal information about the involvement of statistics and statisticians with the early history of parapsychology. Next, it is argued that most nonstatisticians do not appreciate the connection between power and "successful" replication of experimental effects. Returning to parapsychology, a particular experimental regime is examined by summarizing an extended debate over the interpretation of the results. A new set of experiments designed to resolve the debate is then reviewed. Finally, meta-analyses from several areas of parapsychology are summarized. It is concluded that the overall evidence indicates that there is an anomalous effect in need of an explanation.
Mediums claim to be able to communicate with the deceased. Such claims attract a considerable amount of public interest and, if valid, have important implications for many areas of psychology. For over 100 years, researchers have tested alleged mediums. This work has obtained mixed results and provoked a considerable amount of methodological debate. This paper reviews the key issues in this debate, describes how the authors devised a method of testing that aimed to prevent the many problems that have hindered past research, and how they then used this method to test several professional mediums. The results of this work did not support the existence of genuine mediumistic ability. Competing interpretations of these results are discussed, along with ways in which the methodology presented in the paper could be used to assess conceptually similar, but non-paranormal, claims made in clinical, occupational and forensic contexts.
The low reproducibility rate in social sciences lead researchers to hesitate to accept published findings at their face value. It became apparent that the field is lacking the tools necessary both to demonstrate and to verify credibility of research reports. In the present paper, we describe tools and methodologies that let researchers craft highly credible research projects, and allow their peers to verify this credibility. We demonstrate the application and feasibility of these methods in a fully transparent multi-lab replication of Bem’s experiment 1 (2011), which was co-designed by a consensus panel including both proponents and opponents of the hypothesis driving the original study. After the consensus design process, the study protocol underwent extensive piloting. In the main study, we applied direct data deposition, in combination with born-open data and real-time research report to extend transparency to protocol delivery and data collection. We also used laboratory logs and video documented trial sessions to ascertain as-intended protocol delivery by the experimenters, and external research auditors to monitor research integrity. We found X% successful guesses in our study while Bem reported 53.07% success rate. The effect reported by Bem was not/was replicated in our study/This study outcome did not reach the pre-specified criteria to be able to support or contradict Bem’s findings. [Conclusions about the usefulness and feasibility of the approach will be added based on the experiences with using the credibility-enhancing methodologies].
Publication bias is a major threat to the validity of a meta-analysis resulting in overestimated effect sizes. P-uniform is a meta-analysis method that corrects estimates for publication bias, but the method overestimates average effect size in the presence of heterogeneity in true effect sizes (i.e., between-study variance). We propose an extension and improvement of the p-uniform method called p-uniform*. P-uniform* improves upon p-uniform in three important ways, as it (i) entails a more efficient estimator, (ii) eliminates the overestimation of effect size in case of between-study variance in true effect sizes, and (iii) enables estimating and testing for the presence of the between-study variance in true effect sizes. We compared the statistical properties of p-uniform* with the selection model approach of Hedges (1992) as implemented in the R package “weightr” and the random-effects model in both an analytical and a Monte-Carlo simulation study. Results revealed that the statistical properties of p-uniform* and the selection model approach were generally comparable and outperformed the random-effects model if publication bias was present. We demonstrate that both methods estimate average true effect size rather well with two or more and between-study variance with ten or more primary studies in a meta-analysis. However, both methods do not perform well if the meta-analysis only includes statistically significant studies. We offer recommendations for correcting meta-analyses for publication bias in practice, and provide an R package and an easy-to-use web application for applying p-uniform*.
Studies combined in a meta-analysis often have differences in their design and conduct that can lead to heterogeneous results. A random-effects model accounts for these differences in the underlying study effects, which includes a heterogeneity variance parameter. The DerSimonian-Laird method is often used to estimate the heterogeneity variance, but simulation studies have found the method can be biased and other methods are available. This paper compares the properties of nine different heterogeneity variance estimators using simulated meta-analysis data. Simulated scenarios include studies of equal size and of moderate and large differences in size. Results confirm that the DerSimonian-Laird estimator is negatively biased in scenarios with small studies, and in scenarios with a rare binary outcome. Results also show the Paule-Mandel method has considerable positive bias in meta-analyses with large differences in study size. We recommend the method of restricted maximum likelihood (REML) to estimate the heterogeneity variance over other methods. However, considering that meta-analyses of health studies typically contain few studies, the heterogeneity variance estimate should not be used as a reliable gauge for the extent of heterogeneity in a meta-analysis. The estimated summary effect of the meta-analysis and its confidence interval derived from the Hartung-Knapp-Sidik-Jonkman method is more robust to changes in the heterogeneity variance estimate and shows minimal deviation from the nominal coverage of 95% under most of our simulated scenarios.
Modern research with mediums-individuals who regularly experience and report communication from the deceased-includes investigations of mediums' accuracy, psychology, phenomenology, and electrophysiology and the therapeutic potential of mediumship readings for the bereaved. Anecdotal reports imply that chronic medical problems may be a serious concern for mediums.
The aim of this study was two-fold: (I) to systematically investigate the hematological and psychophysiological correlates of anomalous information reception (AIR, the reporting of accurate and specific information about the deceased in the absence of prior knowledge, feedback, or deceptive means) and (II) to compare the reported health issues of mediums and non-mediums.
(I) A repeated-measures design in which mediums engaged in blinded mediumship readings and a control condition was used. (II) A parallel-groups design was used to compare mediums' and non-mediums' responses to an anonymous online survey regarding their health issues.
(I) Data was collected from five Windbridge Certified Research Mediums. (II) Survey responses from 125 mediums were compared to responses from 222 non-mediums.
Main outcome measures:
(I) General physiological measures and 28 hematological elements were assessed. (II) Reports regarding autoimmune disease diagnoses and specific ailments by organ system were collected.
Novel findings from this study included the following: (I) No significant hematological or physiological changes were seen in the mediums when pre- and post-condition comparisons were made for the counter-balanced sessions. (II) Compared to non-mediums, more mediums reported having at least one autoimmune disease (35.2% vs. 18.9%; p = 0.00076; z = 3.37; h = 0.4). Mediums also reported experiencing more health issues than did non-mediums (8.08 ± 5.38 vs. 5.09 ± 4.17 symptoms; p < 0.000001, g = 0.6). Specifically, more mediums than non-mediums (all p < 0.004) reported water retention (19.2% vs. 5.0%, z = 4.23, h = 0.5), bruising easily (20.0% vs. 9.0%, z = 2.93, h = 0.3), gastrointestinal issues (35.2% vs. 18.5%, z = 3.48, h = 0.4), headaches/migraines (26.4% vs. 11.3%, z = 3.63, h = 0.4), asthma (20.0% vs. 9.0%, z = 2.93, h = 0.3), food intolerances (28.0% vs. 9.9%, z = 4.37, h = 0.5), and sleep disturbances (40.8% vs. 14.9%, z = 5.41 h = 0.6). The proportions of participants reporting exophthalmos, chronic fatigue syndrome, and ankle sprains were not different.
This article presents a comprehensive integration of current experimental evidence and theories about so-called parapsychological (psi) phenomena. Throughout history, people have reported events that seem to violate the common sense view of space and time. Some psychologists have been at the forefront of investigating these phenomena with sophisticated research protocols and theory, while others have devoted much of their careers to criticizing the field. Both stances can be explained by psychologists’ expertise on relevant processes such as perception, memory, belief, and conscious and nonconscious processes. This article clarifies the domain of psi, summarizes recent theories from physics and psychology that present psi phenomena as at least plausible, and then provides an overview of recent/updated meta-analyses. The evidence provides cumulative support for the reality of psi, which cannot be readily explained away by the quality of the studies, fraud, selective reporting, experimental or analytical incompetence, or other frequent criticisms. The evidence for psi is comparable to that for established phenomena in psychology and other disciplines, although there is no consensual understanding of them. The article concludes with recommendations for further progress in the field including the use of project and data repositories, conducting multidisciplinary studies with enough power, developing further nonconscious measures of psi and falsifiable theories, analyzing the characteristics of successful sessions and participants, improving the ecological validity of studies, testing how to increase effect sizes, recruiting more researchers at least open to the possibility of psi, and situating psi phenomena within larger domains such as the study of consciousness.
Sudduth provides a critical exploration of classical empirical arguments for survival arguments that purport to show that data collected from ostensibly paranormal phenomena constitute good evidence for the survival of the self after death. Utilizing the conceptual tools of formal epistemology, he argues that classical arguments are unsuccessful.
Frederic William Henry Myers (1843-1901) was a classical scholar who in mid-career turned to the investigation of psychic phenomena. After studying, and later teaching, Classics at Trinity College, Cambridge he resigned his lectureship in 1869, became an inspector of schools, and campaigned for women's higher education. With the encouragement of former colleagues he began a scientific investigation of spiritualism and related phenomena, and in 1882 he helped to found the Society for Psychical Research. This two-volume work, first published posthumously in 1903, contains the fullest statement of Myers' influential theory of the 'subliminal self', which he developed by combining his research into psychic phenomena with his in-depth reading about the latest advances in psychology and related fields. His deeply intellectual approach is evident throughout the book, which analyses a huge amount of interesting data. Volume 2 discusses apparitions, trances and bodily possession.
Certain mediums are able to report accurate and specific information about the deceased loved ones (termed discarnates) of living people (termed sitters) even without any prior knowledge about the sitters or the discarnates and in the complete absence of any sensory feedback. This study aimed to investigate the phenomenology associated with, and accuracy of, readings for discarnates by claimant mediums under beyond double-blind conditions. At baseline, directly after a counterbalanced control condition, and after each of two identically formatted, scheduled phone readings for paired discarnates, 19 claimant mediums completed the Phenomenology of Consciousness Inventory (PCI). The two readings were then given global accuracy scores by the blinded sitters associated with the two discarnates. A significant anomalous information reception effect was demonstrated. However, this study did not identify any phenomenological variables that were correlates of mediums' abilities. It would be prudent for future researchers to focus on the development of a quantitative measure specifically designed to investigate the phenomenology of mediumistic experience.
The study of mediumship is important because if mediumistic abilities are real, they would provide empirical support for non-reductionist theories of the mind, thus having major implications to our understanding of the mind-brain relationship. This study investigated the alleged mediumship of Chico Xavier, a very prolific and influential ‘medium’ in Brazil.
To investigate the accuracy of the information conveyed in Xavier’s ‘psychographed’ letters (i.e., letters allegedly authored by a deceased personality) and to explore the possible explanations for it.
After a systematic search for Xavier’s psychographed letters we selected one set of 13 letters allegedly written by a same spiritual author (JP). The letters were initially screened for the identification of items of information that were objectively verifiable. The accuracy of the information conveyed by these items and the estimated likelihood of the Xavier’s access to the information via normal means were rated using Fit and Leak scales based on documents and interviews carried out with the sister and friends of JP.
We identified 99 items of verifiable information conveyed on these 13 letters; 98% of these items were rated as ‘Clear and Precise Fit,’ and no item was rated as ‘no Fit.’ We concluded that normal explanations for accuracy of the information (i.e., fraud, chance, information leakage, and cold reading) were only remotely plausible. These results seem to provide empirical support for non-reductionist theories of consciousness.
This article proposes a standard, easy-to-interpret effect size estimate for one-sample research. The proportion index (π) shows the hit rate on a scale on which .50 is always the null value regardless of the number of equally likely choices. The index π is useful in the design of one-sample research because it can guide the best choice of number of response alternatives. Significance tests and confidence limits are readily computed. For meta-analyses of one-sample studies, tests of heterogeneity of a set of πs and contrasts among them are described. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Presents an account of two mediumship sessions in Bali, describing the ritual involved with quotes from parts of the transcripts. Mediumship within the Balinese context is interpreted within the worldview of that culture, and compared with the traditional Western perspective. Mediums are viewed as (and called) healers in Bali. Employing an explanation of the Balinese view of illness and health, mediumship is placed within that healing context. The information-giving function of mediumship, which is primary in Western views of mediumship, is attenuated in Bali because, in an important sense, the medium becomes the message. It is suggested both that psi may play an important role in the latter process and that this view may help us to understand psi. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Reports the case of a "drop-in" communicator who manifested at a sitting in Italy in 1948 and furnished correct information about a murder that had occurred in the US nearly 20 yrs before the sitting. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
I discuss the construction of Balinese trance behaviors using two examples of trance possession in temple ceremonies. The view that trance states are socially constructed has long roots in anthropology. However, a closer examination of this view is warranted. In particular, I am interested in the question of the possible diversity of the constructed behavior. On the one hand, one may expect a set of general trance behaviors or experiences throughout a given society—e.g. that vision quests in a particular tribe will contain common elements, but these will vary from tribe to tribe (Lowie 1963). On the other hand, a society may offer the general outlines of acceptable trance behavior or experience, but expect them to be radically individual, depending, e.g., on the particular revelatory experience of the person. The Balinese construction of trance fits neither of these poles; rather, trance behaviors are contextualized to a particular temple but not to individual persons. Thus, the trances of the Balinese exhibit a high degree of variety from locale to locale. This unusual variety is due to two factors: a key element of Balinese Hinduism, adat (local custom), as well as a unique feature of how Balinese deities (who possess individuals in trance) are conceived.
Growing public interest in the phenomenon of mediumship, particularly among bereaved persons, suggests the need for renewed controlled studies of mediums, both to provide potential clients with criteria for judging mediums and to help researchers learn whether they can produce specific and accurate information to which they have had no normal access and, if so, under what conditions. Two research studies were conducted in which mediums provided readings about particular deceased persons to a proxy sitter. The real sitters then blindly rated the reading that was intended for them along with several control readings. In the first study, the results were not significant. In the second, much larger study the results were highly significant (z = -3.89, p < 0.0001, 2-tailed). The authors discuss 2 possible weaknesses of the successful study and indicate some directions for further research.
Investigating the information reported by mediums is ultimately important in determining the relationship between brain and consciousness in addition to being of deep concern to the public.
This triple-blind study was designed to examine the anomalous reception of information about deceased individuals by research mediums under experimental conditions that eliminate conventional explanations.
Eight University of Arizona students served as sitters: four had experienced the death of a parent; four, a peer. Eight mediums who had previously demonstrated an ability to report accurate information in a laboratory setting performed the readings.
To optimize potential identifiable differences between readings, each deceased parent was paired with a same-gender deceased peer. Sitters were not present at the readings; an experimenter blind to information about the sitters and deceased served as a proxy sitter. The mediums, blind to the sitters' and deceased's identities, each read two absent sitters and their paired deceased; each pair of sitters was read by two mediums. Each blinded sitter then scored a pair of itemized transcripts (one was the reading intended for him/her; the other, the paired control reading) and chose the reading more applicable to him/her.
The findings included significantly higher ratings for intended versus control readings (p = 0.007, effect size = 0.5) and significant reading-choice results (p = 0.01).
The results suggest that certain mediums can anomalously receive accurate information about deceased individuals. The study design effectively eliminates conventional mechanisms as well as telepathy as explanations for the information reception, but the results cannot distinguish among alternative paranormal hypotheses, such as survival of consciousness (the continued existence, separate from the body, of an individual's consciousness or personality after physical death) and super-psi (or super-ESP; retrieval of information via a psychic channel or quantum field).
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