Hopping, skipping or jumping to conclusions? Clarifying the role of the JTC bias in delusions

  title={Hopping, skipping or jumping to conclusions? Clarifying the role of the JTC bias in delusions},
  author={Cordelia Fine and Mark R Gardner and Jillian Craigie and Ian Gold},
  journal={Cognitive Neuropsychiatry},
  pages={46 - 77}
Introduction. There is substantial evidence that patients with delusions exhibit a reasoning bias—known as the “jumping to conclusions” (JTC) bias—which leads them to accept hypotheses as correct on the basis of less evidence than controls. We address three questions concerning the JTC bias that require clarification. Firstly, what is the best measure of the JTC bias? Second, is the JTC bias correlated specifically with delusions, or only with the symptomatology of schizophrenia? And third, is… 

The jumping to conclusions bias in delusions: specificity and changeability.

It is demonstrated that JTC is linked to delusions but that this association is not unique, and patients with delusions are principally able to adapt their decisions to altered conditions but still decide relatively quickly even when decisions have negative consequences.

Jumping to Conclusions About the Beads Task? A Meta-analysis of Delusional Ideation and Data-Gathering.

A random-effects meta-analysis of individual participant data provides some provisional support for continuum theories of psychosis and cognitive models that implicate the JTC bias in the formation and maintenance of delusions.

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

Over-adjustment or miscomprehension? A re-examination of the jumping to conclusions bias

It was concluded that the ‘premature decisions’ component of the JTC bias remains a feature of decision-making in schizophrenia, but that previously reported ‘over-adjustment’ effects are likely to be influenced by miscomprehension of the beads task instructional set.

[The role of the jumping to conclusion bias in delusions formation].

The article in question contains the review of the results of the jumping to conclusion bias in people with delusions, and discusses the main hypotheses explaining the relations between the hasty decision making and the delusions formation.

Jumping to conclusions and perceptions in early psychosis: Relationship with delusional beliefs

The results suggest that the JTP bias may be a trait characteristic in those with a propensity to delusions, and that these individuals may also show a bias away from threat.

Jumping to delusions in early psychosis

A jumping-to-conclusions bias and an over-adjustment bias co-occurred in the early psychosis patients and implications are discussed concerning the role of such biases in delusion-proneness.

The jumping to conclusions bias associated with symptoms in schizophrenia: which factors influence this bias?

Education levels, anxiety and negative symptoms of individuals with schizophrenia were found to affect JTC bias on 90:10 version of task, whereas positive symptoms and impulsivity levels were related to JTC biases on 60:40 version.



Jumping to conclusions in delusional and non-delusional schizophrenic patients.

Whether currently deluded and non-deluded schizophrenic patients perform differently on three tasks tapping probabilistic reasoning is investigated to provide further evidence for state and trait characteristics of abnormal reasoning in paranoid schizophrenia.

Specificity of the jump-to-conclusions bias in deluded patients.

The results suggest that JTC is specific to delusions rather than diagnosis, and to data gathering rather than a general deficit in reasoning.


Evidence for the existence of the data-gathering, but not the probability judgment, part of the JTC reasoning bias was found in the delusion-prone individuals, which suggests that it may be involved in the formation, rather than merely the maintenance, of delusional beliefs.

Reasoning biases in delusion-prone individuals.

Although individuals high in delusional ideation were not found to have a general reasoning bias, some evidence of a more specific bias was found and it is thought that these aberrations may play some role in delusion formation in schizophrenia and paranoia.

Data gathering: biased in psychosis?

This study examined whether the probabilistic reasoning bias referred to as a "jumping-to-conclusions" (JTC) style of reasoning, which, according to previous research, is associated with particular

Cognitive functioning in delusions: a longitudinal analysis.

People with delusions jump to conclusions: a theoretical account of research findings on the reasoning of people with delusions

Recent multifactorial models of psychotic symptoms such as delusions emphasize a role for reasoning biases in the maintenance of delusional beliefs. Specifically, people with delusions are seen to

Delusions and delusional reasoning.

In 2 studies, delusional participants assigned higher probabilities to narratives of actual delusions than participants with no history of delusions, consistent with the Bayesian model of delusion formation proposed by D. R. Hemsley and P. Kaney (1994) and with R. Garety (1986).

Normal and abnormal reasoning in people with delusions.

People with delusions have a data-gathering bias rather than a difficulty in employing the data in reasoning, which is a consequence of impulsiveness or memory deficit, rather than an absolute deficit in reasoning.

Cognitive approaches to delusions: a critical review of theories and evidence.

A multi-factorial model of delusion formation and maintenance incorporating a data-gathering bias and attributional style, together with other factors (e.g. perceptual processing, meta-representation) is consistent with the current evidence.