Individual differences in hallucination-proneness and experimentally induced false perceptual experiences

Abstract

Previous research (e.g. Tsakanikos and Reed, 2005; Tsakanikos, 2006) has suggested that unusual experiences and hallucination-proneness can predict false perceptual experiences in the laboratory. Such experiences are typically induced under conditions of increased perceptual ambiguity, experimentally manipulated though presentation speed and frequency of moving images. Nevertheless, it remains unclear how specific experimental parameters can interact with relevant participant characteristics such as illicit substance use, hallucination-proneness and coping mechanisms. In the present study ( N = 80), undergraduate students were presented with 3-D fast moving words and non-word trials under different experimental conditions, and were asked to write down any real word they could see. This was a 2 (speed: 750 ms VS 900 ms) × 2 (frequency: 25% × 75%) experimental design. Participants also completed a battery of self-report measures on unusual experiences, hallucination-proneness, substance use and coping mechanisms. The results are discussed in terms of current cognitive models of hallucinations.