Jumping to conclusions: the association between delusional ideation and reasoning biases in a healthy student population

Cognitive theorists have focused specifically on reasoning biases, in particular ‘Jumping to Conclusions’ (JTC), in an attempt to understand delusional experiences. The present study aimed to assess the association between the JTC reasoning bias and dimensions of delusional ideation among a sample of healthy undergraduate university students. Delusional ideation was assessed using the Peters Delusion Inventory (PDI-21). The JTC reasoning bias was assessed using two ratios of the Beads Task. The findings revealed that those participants who completed the 85:15 ratio beads task and who exhibited higher levels of delusional ideation did not demonstrate a JTC bias. However, participants who completed the more difficult 60:40 variant of the beads task and who exhibited higher levels of delusional ideation were more likely to demonstrate a JTC bias. JTC made a significant contribution to the total variance explained for the PDI Total, and each of the three subscales of the PDI. Healthy individuals display a tendency to ‘JTC’ and this is associated with delusional ideation, therefore representative of the continuum perspective, that these experiences are not confined to clinical populations. Implications of these findings and future directions for research in this area are also discussed.