Paranoia, persecutory delusions and attributional biases Ryan McKay * , Robyn Langdon, Max Coltheart Macquarie Centre for Cognitive Science (MACCS), Macquarie University, Sydney, NSW, 2109, Australia Received 11 May 2005; accepted 13 June 2005 Abstract An influential model of persecutory delusions put forward by Bentall and colleagues hypothesizes that persecutory-deluded patients avoid the activation of negative self-beliefs by making externalising, personalising attributions for negative events. The first study reported here used a new instrument for the measurement of persecutory ideation, the Paranoid, Persecutory and Delusion-Proneness Questionnaire, to investigate whether attributional biases are associated with subclinical persecutory ideation. The second study extended this investigation by re-examining associations between attributional biases and persec- utory delusions. Both studies used the Internal, Personal and Situational Attributions Questionnaire to measure attributional style. No evidence was found for a connection between attributional biases and subclinical persecutory ideation. Furthermore, there was no support for an association between persecutory delusions and an externalising bias, and only marginal support for the hypothesized relationship between persecutory delusions and a personalising bias. These results suggest that the putative link between persecutory ideation and attributional biases only manifests (if at all) when persecutory ideation is of delusional intensity, and that it is confined to a personalising bias. D 2005 Elsevier Ireland Ltd. All rights reserved. Keywords: Theoretical models; Psychoanalysis; Cognitive biases; Attributions 1. Introduction Bentall and colleagues (e.g., Bentall et al., 1994; Bentall and Kaney, 1996; Kinderman and Bentall, 1996b, 1997) are influential advocates of a psycho- dynamically inflected model of persecutory delu- sions. These authors assume that patients with persecutory delusions harbour latent negative self- beliefs that are susceptible to activation by negative life events. In this respect, persecutory-deluded patients are thought to be similar to depressed patients. Unlike depressed patients, however, patients with persecutory delusions are hypothesised to defend against the activation of negative self-beliefs by attributing negative events to the actions of other agents. Through such external–personalising attribu- tions, individuals with persecutory delusions main- tain their overt self-esteem by effectively projecting 0165-1781/$ - see front matter D 2005 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.psychres.2005.06.004 * Corresponding author. Present address: c/o Center For Cognitive Studies, 11 Miner Hall, Tufts University, Medford, MA 02155, USA. Tel.: +1 617 627 3297. E-mail address: ryan@maccs.mq.edu.au (R. McKay). Psychiatry Research 136 (2005) 233 – 245 www.elsevier.com/locate/psychres