Validating a dimension of doubt in decision-making: A proposed endophenotype for obsessive-compulsive disorder

Abstract

Doubt is subjective uncertainty about one’s perceptions and recall. It can impair decision-making and is a prominent feature of obsessive-compulsive disorder (OCD). We propose that evaluation of doubt during decision-making provides a useful endophenotype with which to study the underlying pathophysiology of OCD and potentially other psychopathologies. For the current study, we developed a new instrument, the Doubt Questionnaire, to clinically assess doubt. The random dot motion task was used to measure reaction time and subjective certainty, at varying levels of perceptual difficulty, in individuals who scored high and low on doubt, and in individuals with and without OCD. We found that doubt scores were significantly higher in OCD cases than controls. Drift diffusion modeling revealed that high doubt scores predicted slower evidence accumulation than did low doubt scores; and OCD diagnosis lower than controls. At higher levels of dot coherence, OCD participants exhibited significantly slower drift rates than did controls (q<0.05 for 30%, and 45% coherence; q<0.01 for 70% coherence). In addition, at higher levels of coherence, high doubt subjects exhibited even slower drift rates and reaction times than low doubt subjects (q<0.01 for 70% coherence). Moreover, under high coherence conditions, individuals with high doubt scores reported lower certainty in their decisions than did those with low doubt scores. We conclude that the Doubt Questionnaire is a useful instrument for measuring doubt. Compared to those with low doubt, those with high doubt accumulate evidence more slowly and report lower certainty when making decisions under conditions of low uncertainty. High doubt may affect the decision-making process in individuals with OCD. The dimensional doubt measure is a useful endophenotype for OCD research and could enable computationally rigorous and neurally valid understanding of decision-making and its pathological expression in OCD and other disorders.

Transfer of information across repeated decisions in general and in obsessive–compulsive disorder

“…The drift-diffusion model has been studied in a wide range of contexts and domains including the dot motion task and has converging support from both behavioral and neural data (13,15,17,(28)(29)(30). Previous work has shown specifically that drift rate is impaired (reduced) both in patients with OCD and in subclinical individuals with high levels of self-reported OCD symptoms (21)(22)(23)(24). Moreover, impairments are larger for easier decisions (21,24).…”

“…This also aligned within a more general goal we had for developing a paradigm that was complex enough to ask a wide array of questions about continued deliberation across decisions but simple enough to reliably model and recover parameter values at the individual subject level without onerously long testing sessions. Finally, numerous studies have documented impairments within single decision episodes in this task both in patients with OCD and in subclinical individuals high on the OCD spectrum (21)(22)(23)(24) (but see also ref. 25), making it an obvious choice for extending the investigation of individual differences across repeated decision episodes.…”

Striatum-Mediated Deficits in Stimulus-Response Learning and Decision-Making in OCD

“…Additionally, decision-making deficits seen in OCD can be related to pathological doubt, a common phenomenon seen in OCD. Studies have shown that patients with OCD often experience uncertainty when making decisions due to a lack of confidence in their own perception, attention, and memory (77)(78)(79). In decision-making tasks, this can manifest as longer response times compared to healthy controls (77).…”

Compulsiveness Drives Evidence Accumulation During Ambiguity

“…', or 'Should I go to the pub at the end of lockdown?' Obsessive-compulsive disorder (OCD) [1][2][3] has been postulated to be characterized by impairments in doubt, potentially triggering pathological symptoms such as checking or washing, which, following the execution of repeated actions [4][5][6] further increases the doubt 1 .…”

“…But computational parameters estimated using a hierarchical drift-diffusion model (HDDM) showed an increase in the threshold parameter (which indicates the amount of evidence accumulated before a choice is selected) in OCD patients when the randomness of the dots increased 9 . OCD patients with higher doubt scores had low drift rates and lower certainty in their decisions 2 . Hauser and colleagues show increased thresholds 22,23 and decreased drift rates along with meta-cognitive deficits in individuals with higher compulsive traits 24 .…”