Test of Target Engagement of Ambiguity Aversion

Not Applicable

Not yet recruiting

• Conditions: Intolerance of Uncertainty; Anxiety; Depression, Anxiety; Intolerance of Uncertainty; Anxiety

• Registration Number: NCT06962527
• Lead Sponsor: Northwestern University

Brief Summary

The present work aims to test whether a single session intervention alters ambiguity aversion, both in terms of people's decision making and their brain responses to ambiguous choices.

Detailed Description

In this trial, participants will be randomized to one of two single session interventions (SSI). They will complete a decision making task before and after the SSI to measure their behavioral and brain responses to ambiguity, all on the same day. They will also complete a brief measure of hopelessness before and after the SSI. The main analysis will compare changes in ambiguity aversion before and after the interventions. Participants will also be asked to complete questionnaires before completing the task and SSI. The questionnaires will be about the participant's emotions and symptoms of depression and anxiety, personality, and avoidance/tolerance of uncertainty.

Study Timeline

• Status Verified: 2025-01
• Study First Submitted: 2025-01-27
• Study First Submitted QC: 2025-04-29
• Last Update Submitted: 2025-04-29
• Study First Posted: 2025-05-08
• Last Update Posted: 2025-05-08
• Study Start: 2025-06-01
• Primary Completion: 2029-07-01
• Study Completion: 2029-12-31

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 140

Inclusion Criteria

1. Ages 25 to 60
2. Right-handed
3. Ability to read and write English
4. Capacity to provide informed consent
5. Intolerance of uncertainty score ≥ -0.5 standard deviation below the mean (31st percentile)

Exclusion Criteria

1. Personal history of psychosis, mania, or hypomania
2. Personal history of autism spectrum disorder
3. IQ < 80 as determined by the Wechsler Test of Adult Reading
4. Head injury with greater than 120 seconds loss of consciousness
5. Neurological condition (e.g., epilepsy, Parkinson's, cerebral palsy, history of stroke)
6. Currently pregnant
7. Use of any implanted electrical device (e.g., pacemaker, spinal stimulator, vagal nerve stimulator, Inspire sleep apnea device, etc.).

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Behavioral ambiguity aversion	1 hour	Computational modeling will be used to extract two parameters indicative of behavioral ambiguity aversion (AA) from a risk and ambiguity task completed once before and once after the intervention. This results in two variables per participant: one which indicates categorical AA (i.e., their tendency to choose the unambiguous choice regardless of the amount of ambiguity present) and one which indicates continuous AA (i.e., how the amount of ambiguity influences people's choice).
Beck Hopelessness Scale-4 (BHS-4)	1 hour	The BHS-482 is a four-item self-report scale that will be used to assess hopelessness before and after the experimental intervention (scale assesses hopelessness "right now, in this moment") to determine whether the intervention was effective in eliciting change in a clinically meaningful construct. It has good psychometric properties. Participants will complete the Beck Hopelessness Scale (BHS-4) before and after the intervention as a manipulation check that the single session intervention (SSI) "worked" in the event that the other primary outcomes exhibit resistance to change.
Event-related potential responses to ambiguous choices	1 hour	From EEG data collected during the risk and ambiguity task, event-related potentials (ERPs)-time-locked electroencephalogram signals with millisecond resolution-will be extracted to yield one variable per participant indicating mean brain activity to ambiguous choices. Pilot data and small prior studies have consistently found an attenuated P300-like component (albeit later than usual, around 350-500ms) to ambiguous relative to unambiguous choices similar to those on this task.

Trial Locations

Locations (1)

Northwestern University; 🇺🇸 Chicago, Illinois, United States