The Relationship Between Performance on a Prototype Measure of Perceptual Defence / Vigilance and Psi Performance

Based on the premise that psi information is initially processed at an unconscious level, parapsychologists have repeatedly drawn parallels between subliminal perception and extrasensory perception. For instance, defensiveness resistance to, or distortion of, unpleasant or threatening information has been considered to affect both subliminal and extrasensory perception. This thesis reviews studies suggesting a relationship between 'defensiveness' and psi performance, and reports the outcome of a meta¬ analysis of a subset of these studies that used the Defence Mechanism Test as a measure of defensiveness. The review and meta-analysis suggest that there is a need for independent replication of the defensiveness-psi findings, and for an extension of this line of research. Difficulties with the various methods used for measuring defensiveness are identified, and the development of an alternative, prototype measure of 'perceptual defence/vigilance', using a 'subliminal perception' paradigm, is described. Seven experiments are conducted to explore the relationship between defensiveness and psi using this prototype indicator. The first three are preliminary studies aimed at developing the prototype indicator of perceptual defence/vigilance, and in two of these studies comparisons are made between perceptual defence/vigilance and psi performance. Experiment 4 describes a systematic comparison of perceptual defence/vigilance and ESP performance, while experiment 5 compares defensiveness with ESP scoring before and after training with various mental techniques reputed to enhance psi performance. Experiment 6 explores variations in methodology and scoring systems associated with the prototype measure of perceptual defence/vigilance. Experiment 7 compares perceptual defence/vigilance and ESP performance, including a theory-based examination of 'implicit' and 'explicit' measures of defensiveness and ESP. The main findings of these experiments are that perceptual defensiveness/vigilance consistently correlates in the predicted direction with PK, with forced-choice ESP, and with 'unconscious' ESP, but that there appears to be no systematic relationship between defensiveness and free-response ESP before and after training. Importantly, there is also a consistent correlation between defensiveness and a questionnaire measure of neuroticism, that provides converging evidence of the validity of the prototype indicator of perceptual defence/vigilance. The final chapter summarises and synthesises the findings of the experiments conducted, and makes suggestions for future research. It is concluded that while there is a need for further, more systematic development of the perceptual defence/vigilance apparatus, these experiments have shown the potential of this prototype indicator to be a useful tool, both for parapsychologists wishing to explore the psi process, including its relationship to defensiveness, and for psychologists interested in enhancing human performance.