Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-26T17:27:23.508Z Has data issue: false hasContentIssue false
  • English
  • Français

Delusion proneness and ‘jumping to conclusions’: relative and absolute effects

Published online by Cambridge University Press:  30 September 2014

L. van der Leer ,
B. Hartig ,
M. Goldmanis  and
R. McKay
L. van der Leer
Affiliation:
ARC Centre of Excellence in Cognition and its Disorders, Department of Psychology, Royal Holloway, University of London, Egham, Surrey, UK
B. Hartig
Affiliation:
Department of Economics, Royal Holloway, University of London, Egham, Surrey, UK
M. Goldmanis
Affiliation:
Department of Economics, Royal Holloway, University of London, Egham, Surrey, UK
R. McKay*
Affiliation:
ARC Centre of Excellence in Cognition and its Disorders, Department of Psychology, Royal Holloway, University of London, Egham, Surrey, UK
*
* Address for correspondence: Dr R. McKay, Ph.D., ARC Centre of Excellence in Cognition and its Disorders, Department of Psychology, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK. (Email: ryantmckay@mac.com)
Get access Rights & Permissions [Opens in a new window]

Abstract

Background.

That delusional and delusion-prone individuals ‘jump to conclusions’ is one of the most robust and important findings in the literature on delusions. However, although the notion of ‘jumping to conclusions’ (JTC) implies gathering insufficient evidence and reaching premature decisions, previous studies have not investigated whether the evidence gathering of delusion-prone individuals is, in fact, suboptimal. The standard JTC effect is a relative effect but using relative comparisons to substantiate absolute claims is problematic. In this study we investigated whether delusion-prone participants jump to conclusions in both a relative and an absolute sense.

Method.

Healthy participants (n = 112) completed an incentivized probabilistic reasoning task in which correct decisions were rewarded and additional information could be requested for a small price. This combination of rewards and costs generated optimal decision points. Participants also completed measures of delusion proneness, intelligence and risk aversion.

Results.

Replicating the standard relative finding, we found that delusion proneness significantly predicted task decisions, such that the more delusion prone the participants were, the earlier they decided. This finding was robust when accounting for the effects of risk aversion and intelligence. Importantly, high-delusion-prone participants also decided in advance of an objective rational optimum, gathering fewer data than would have maximized their expected payoff. Surprisingly, we found that even low-delusion-prone participants jumped to conclusions in this absolute sense.

Conclusions.

Our findings support and clarify the claim that delusion formation is associated with a tendency to ‘jump to conclusions’. In short, most people jump to conclusions, but more delusion-prone individuals ‘jump further’.

Keywords

Decision makingdelusion pronenessdelusionsexperimental economicsjumping to conclusions
Type
Original Articles
Information
Psychological Medicine , Volume 45 , Issue 6 , April 2015 , pp. 1253 - 1262
Copyright
Copyright © Cambridge University Press 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Arthur, WJ, Day, DV (1994). Development of a short form for the Raven Advanced Progressive Matrices test. Educational and Psychological Measurement 54, 394–403.CrossRefGoogle Scholar
Averbeck, BB, Evans, S, Chouhan, V, Bristow, E, Shergill, SS (2011). Probabilistic learning and inference in schizophrenia. Schizophrenia Research 127, 115–122.CrossRefGoogle ScholarPubMed
Balzan, R, Delfabbro, P, Galletly, C (2012 a). Delusion-proneness or miscomprehension? A re-examination of the jumping-to-conclusions bias. Australian Journal of Psychology 64, 100–107.CrossRefGoogle Scholar
Balzan, R, Delfabbro, PH, Galletly, CA, Woodward, TS (2012 b). Over-adjustment or miscomprehension? A re-examination of the jumping to conclusions bias. Australian and New Zealand Journal of Psychiatry 46, 532–540.CrossRefGoogle ScholarPubMed
Beck, AT (1976). Cognitive Therapy and the Emotional Disorders. International Universities Press: New York.Google Scholar
Colbert, SM, Peters, ER (2002). Need for closure and jumping-to-conclusions in delusion-prone individuals. Journal of Nervous and Mental Disease 190, 27–31.CrossRefGoogle ScholarPubMed
Dudley, R, John, CH, Young, AW, Over, DE (1997 a). Normal and abnormal reasoning in people with delusions. British Journal of Clinical Psychology 36, 243–258.CrossRefGoogle ScholarPubMed
Dudley, R, John, CH, Young, AW, Over, DE (1997 b). The effect of self-referent material on the reasoning of people with delusions. British Journal of Clinical Psychology 36, 575–584.CrossRefGoogle ScholarPubMed
Eil, D, Rao, J-M (2012). The good news-bad news effect: asymmetric processing of objective information about yourself. American Economic Journal: Microeconomics 3, 114–138.Google Scholar
Falcone, MA, Murray, RM, Wiffen, BDR, O'Connor, JA, Russo, M, Kolliakou, A, Stilo, S, Taylor, H, Gardner-Sood, P, Paparelli, A, Jichi, F, Di Forti, M, David, AS, Freeman, D, Jolley, S (2014). Jumping to conclusions, neuropsychological functioning, and delusional beliefs in first episode psychosis. Schizophrenia Bulletin. Published online: 22 July 2014 . doi:10.1093/schbul/sbu104.Google ScholarPubMed
Field, A (2009). Discovering Statistics Using SPSS. Sage Publications Ltd: London, UK.Google Scholar
Fine, C, Gardner, M, Craigie, J, Gold, I (2007). Hopping, skipping or jumping to conclusions? Clarifying the role of the JTC bias in delusions. Cognitive Neuropsychiatry 12, 46–77.CrossRefGoogle ScholarPubMed
Fischbacher, U (2007). z-Tree: Zurich toolbox for ready-made economic experiments. Experimental Economics 10, 171–178.CrossRefGoogle Scholar
Garety, PA, Freeman, D (2013). The past and future of delusions research: from the inexplicable to the treatable. British Journal of Psychiatry 203, 327–333.CrossRefGoogle Scholar
Garety, PA, Joyce, E, Jolley, S, Emsley, R, Waller, H, Kuipers, E, Bebbington, P, Fowler, D, Dunn, G, Freeman, D (2013). Neuropsychological functioning and jumping to conclusions in delusions. Schizophrenia Research 150, 570–574.CrossRefGoogle ScholarPubMed
Garrett, N, Sharot, T, Faulkner, P, Korn, CW, Roiser, JP, Dolan, RJ (2014). Losing the rose tinted glasses: neural substrates of unbiased belief updating in depression. Frontiers in Human Neuroscience 8, 639.CrossRefGoogle ScholarPubMed
Greiner, B (2004). The Online Recruitment System ORSEE 2.0: A Guide for the Organization of Experiments in Economics. Working Paper Series in Economics No. 10. Department of Economics, University of Cologne: Germany.Google Scholar
Hertwig, R, Ortmann, A (2001). Experimental practices in economics: a methodological challenge for psychologists? Behavioral and Brain Sciences 24, 383–451.CrossRefGoogle ScholarPubMed
Holt, CA, Laury, SK (2002). Risk aversion and incentive effects. American Economic Review 92, 1644–1655.CrossRefGoogle Scholar
Huq, SF, Garety, PA, Hemsley, DR (1988). Probabilistic judgements in deluded and non-deluded subjects. Quarterly Journal of Experimental Psychology 40A, 801–812.CrossRefGoogle Scholar
Jolley, S, Thompson, C, Hurley, J, Medin, E, Butler, L, Bebbington, P, Dunn, G, Freeman, D, Fowler, D, Kuipers, E, Garety, PA (2014). Jumping to the wrong conclusions? An investigation of the mechanisms of reasoning errors in delusions. Psychiatry Research 219, 275–282. CrossRefGoogle Scholar
Lincoln, TM, Ziegler, M, Mehl, S, Rief, W (2010). The jumping to conclusions bias in delusions: specificity and changeability. Journal of Abnormal Psychology 119, 40–49.CrossRefGoogle ScholarPubMed
McKay, R, Langdon, R, Coltheart, M (2006). Need for closure, jumping to conclusions, and decisiveness in delusion-prone individuals. Journal of Nervous and Mental Disease 164, 422–426.CrossRefGoogle Scholar
McKelvey, RD, Palfrey, TR (1995). Quantal response equilibria for normal form games. Games and Economic Behavior 10, 6–38.CrossRefGoogle Scholar
Moritz, S, Woodward, TS (2005). Jumping to conclusions in delusional and non-delusional schizophrenic patients. British Journal of Clinical Psychology 44, 193–207.CrossRefGoogle ScholarPubMed
Moritz, S, Woodward, TS, Hausmann, D (2006). Incautious reasoning as a pathogenetic factor for the development of psychotic symptoms in schizophrenia. Schizophrenia Bulletin 32, 327–331.CrossRefGoogle ScholarPubMed
Moritz, S, Woodward, TS, Lambert, M (2007). Under what circumstances do patients with schizophrenia jump to conclusions? A liberal acceptance account. British Journal of Clinical Psychology 46, 127–137.CrossRefGoogle ScholarPubMed
Moutoussis, M, Bentall, RP, El-Deredy, W, Dayan, P (2011). Bayesian modelling of jumping-to-conclusions bias in delusional patients. Cognitive Neuropsychiatry 16, 422–447.CrossRefGoogle ScholarPubMed
Peters, E, Joseph, S, Day, S, Garety, PA (2004). Measuring delusional ideation: the 21-item Peters et al. Delusions Inventory (PDI). Schizophrenia Bulletin 30, 1005–1022.CrossRefGoogle Scholar
Phillips, LD, Edwards, W (1966). Conservatism in a simple probability inference task. Journal of Experimental Psychology 72, 346–354.CrossRefGoogle Scholar
Shah, P (2012). Toward a neurobiology of unrealistic optimism. Frontiers in Psychology 3, 1–2.CrossRefGoogle Scholar
Sharot, T (2011). The optimism bias. Current Biology 21, R941–R945.CrossRefGoogle ScholarPubMed
Sharot, T, Korn, CW, Dolan, RJ (2011). How unrealistic optimism is maintained in the face of reality. Nature Neuroscience 14, 1475–1479.CrossRefGoogle ScholarPubMed
Speechley, WJ, Whitman, JC, Woodward, TS (2010). The contribution of hypersalience to the ‘jumping to conclusions’ bias associated with delusions in schizophrenia. Journal of Psychiatry and Neuroscience 35, 7–17.CrossRefGoogle Scholar
van der Leer, L, McKay, R (2014). ‘Jumping to conclusions’ in delusion-prone participants: an experimental economics approach. Cognitive Neuropsychiatry 19, 257–267.CrossRefGoogle ScholarPubMed
Warman, DM, Lysaker, PH, Martin, JM, Davis, L, Haudenschield, SL (2007). Jumping to conclusions and the continuum of delusional beliefs. Behaviour Research and Therapy 45, 1255–1269.CrossRefGoogle ScholarPubMed
White, LO, Mansell, W (2009). Failing to ponder? Delusion-prone individuals rush to conclusions. Clinical Psychology and Psychotherapy 16, 111–124.CrossRefGoogle ScholarPubMed
Woodward, TS, Munz, M, LeClerc, C, Lecomte, T (2009). Change in delusions is associated with change in ‘jumping to conclusions’. Psychiatry Research 170, 124–127.CrossRefGoogle ScholarPubMed