Jumping to Conclusions, Neuropsychological Functioning, and Delusional Beliefs in First Episode Psychosis

Abstract

JTC is present in FEP. The specific association of JTC with clinical delusions supports a state, maintaining role for the bias. The associations of JTC with neuropsychological functioning indicate a separable, trait aspect to the bias, which may confer vulnerability to psychosis. The work has potential to inform emerging interventions targeting reasoning biases in early psychosis.

Jumping To Conclusions, General Intelligence, And Psychosis Liability: Findings From The Multi-Centre EU-GEI Case-Control Study

“…Lower IQ was also found associated with JTC in First Episode Psychosis 27,28 . Nonetheless, other studies on early psychosis did not detect any association with cognition, possibly due to small sample size 29,30 .…”

“…Another possible explanation lies in the fact that JTC seems to be more associated with the continuous distribution of delusions rather than with schizophrenia per se [11][12][13][14][15] . In fact, in a large casecontrol study on FEP patients carried out by Falcone 28 , adjusting for IQ and working memory abolished the relation between JTC and clinical status, but the association between JTC and delusion severity remained. Perhaps building a PRS based on the positive symptom dimension or delusions would be more associated with the bias.…”

“…Although patients at onset seem to adjust their strategy according to the cost of sampling where clearly stated and show more bias to sample less information in the classic task, general cognitive ability still plays an important role in their decision-making behaviour 43,44 . Indeed, the inclusion of general cognitive ability in the relation between JTC and clinical status was reported to substantially decrease or nullify a prior significant association 15,26,28 . Our results are consistent with these studies and provide the first evidence that the genetic variants associated with IQ are negatively correlated with JTC, therefore endorsing the hypothesis that cognition as endophenotype mediates the relation between the bias and the liability for psychotic disorders.…”

Studying Delusions Within Research Domain Criteria: The Challenge of Configural Traits When Building a Mechanistic Foundation for Abnormal Beliefs

“…Much of this work is narrowly balanced on a single task (the beads task), performance on which correlates strongly with working memory (another RDoC construct) and IQ. 19 Differences between psychotic patients and controls on the task are sizeable, Cohen's d = 0.61, 18 but modest compared to d ≈ 1.00 for many other neuropsychological main effects. Risen's context for thinking about how failures in any of several cold cognitive processes might allow for the formation and maintenance of abnormal beliefs may profitably be applied to expanding our thinking about the cognitive neuroscience constructs relevant to delusions.…”

Can delusions be understood linguistically?

“…Many subsequent studies have confirmed this finding (for a review see Garety & Freeman, 2013). However, in much the same way as with theory of mind impairment, these studies have struggled to demonstrate an association with presence or severity of delusions (Dudley et al, 2011; Falcone et al, 2015; Freeman et al, 2014; Garety et al, 2013; Langdon, Ward, & Coltheart, 2010; Lincoln, Ziegler, Mehl, & Rief, 2010; Menon, Pomarol-Clotet, McKenna, & McCarthy, 2006; Moritz & Woodward, 2005; Mortimer et al, 1996; Ochoa et al, 2014; Peters, Thornton, Siksou, Linney, & MacCabe, 2008; So et al, 2012). …”