Optimising methodological practices within psychology: a parapsychology case-study

Abstract

Parapsychology is a contentious research field within psychology. One of the most active research areas is the investigation of the psi hypothesis using the experimental paradigm known as the psi ganzfeld. The psi ganzfeld is a form of mild sensory deprivation, during which participants attempt to perceive a randomly chosen video or image target. The participant is tasked with becoming aware of a target, which may be shown in a different location with no one watching (clairvoyance design), someone watching it in a different location (telepathy design), or the target is chosen after the participant makes their decision (precognition design). During the ganzfeld, participants are asked to vocalise any impressions, sensations, and experiences, which are often audio recorded and are known as the mentation. After the session, participants rate which video or image clip most closely matches their experience. If the participant’s top choice matches the target clip, the session is considered a "hit." However, due to the contentious nature of this experiment, the psi ganzfeld is an ideal case for demonstrating current methodological weaknesses and proposing recommendations that can improve research practices more broadly. This thesis is structured around two overarching themes: the first theme deals with broader methodological issues in psychological research, using the psi ganzfeld experiment as a case study. It discusses the replication crisis in psychology, situating parapsychology within this context, and explores the methodological and statistical challenges common to both fields, such as questionable research practices and the limitations of meta-analyses. A critical examination of meta-analyses of the psi ganzfeld is provided, highlighting how different methodological decisions regarding study inclusion influence the outcomes of literature reviews. An alternative approach to conventional meta-analyses is also presented, demonstrating how to triangulate and synthesise contradictory results from multiple meta-analyses to achieve a more comprehensive understanding of research decisions and study outcomes. The second theme of the thesis focuses on methodological improvements specific to parapsychology, which can also benefit the broader field of psychology. Experimental data from a precognition study demonstrates the flexibility in constructing statistical analyses, via specification curve analysis. Further, verbal reports from ganzfeld precognition studies are analysed using a novel quantitative language analysis, offering new insights into a previously under-examined data source in parapsychology. By applying novel methods to secondary data, these chapters provide a more comprehensive understanding of the data. Given the controversy surrounding the psi ganzfeld task, one of the empirical chapters addresses methodological concerns by proposing an innovative approach to validating study software— an aspect not commonly addressed in either parapsychological or psychological research. The last chapter presents a meta-regression of psi telepathy studies, examining the impact of various methodological features on study outcomes, and offering fresh insights into over 35 years of research. Overall, this thesis highlights the ongoing methodological challenges in psychology, even after the replication crisis produced numerous improvements and recommendations. By using the psi ganzfeld as a case study, it underscores the need for greater transparency regarding researchers’ degrees of freedom when designing reviews, synthesising divergent meta-analyses through innovative approaches like multiverse meta-analyses and employing novel methods to gain deeper insights into existing data. The recommendations and examples drawn from parapsychology, despite its contentious nature, have broader implications for advancing methodological rigour in psychology as a whole.