Learning and Decision-Making in Opioid-Use Disorder
This observational study is looking at how people with opioid-use disorder (OUD) learn and make decisions, compared to people who don't have OUD. Researchers believe that certain types of learning might make it harder for people with addictions to choose long-term benefits over short-term drug use. You would participate in a simple task using pictures and smells to see if there are differences in how your brain makes inferences about outcomes. The study aims to enroll 120 people, including those with OUD who are abstinent, those on agonist treatment (like buprenorphine or methadone), and healthy volunteers. To join, you should be between 21 and 60 years old. The study is trying to understand how these learning processes work.
- Study design
- This is an observational study comparing three groups of participants: those with a history of OUD who are abstinent, those with OUD on agonist treatment, and healthy controls. It is a single-session study with a planned enrollment of 120 participants.
- What's involved
- You would have one visit lasting up to 5 hours. You would need to fast for at least 6 hours before the visit and be willing to smell food odors.
- Compensation
- Not stated in the trial record.
- Follow-up
- Participants will have telephone follow-up at 30 and 60 days after their visit.
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NCT03745339
Outcome Inference in the Sensory Preconditioning Task in Opioid-Use Disorder
Recruiting
Not specifiedAges 21–60ObservationalNational Institute on Drug Abuse (NIDA)Government-funded
~150 participants
Updated 2026-08-28 on ClinicalTrials.gov
At a glance
Recruiting sites
1 of 1 listed site is recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Outcome inferencing in the probe test
Measured over During task
Conditions
Where it's being run
1 sites across 1 statesMaryland1
Study leadership
- Thorsten Kahnt, Ph.D. · PRINCIPAL_INVESTIGATOR · National Institute on Drug Abuse (NIDA)
Who to contact
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Do you actually qualify for this trial?
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Eligibility criteria
Inclusion
Age between 21 and 65 years inclusive. Rationale: objective olfactory impairment grows more prevalent with age; after age 53, the prevalence is 24.5%, increasing to 62.5 % in people aged 80-97 years.
Willing to fast for at least 6 hours prior to the study session and be exposed to food odors. These will be assessed with the "019 Additional History Form" questionnaire.
History of opioid-use disorder (DSM-5), to be assessed via the Mini International Neuropsychiatric Interview (MINI) or the Structured Clinical Interview for DSM-5 (SCID). History of SUDs can include substances in addition to opioids (e.g., cocaine).
Exclusion
Current enrollment in treatment for OUD with buprenorphine or methadone (\>3 weeks on stable dose). Current use of illicit substances during treatment is permissible but not required. Rationale: Again, heterogeneity will be considerable, but what all enrollees will have in common is having sought treatment for their OUD and being currently maintained on an agonist that permits adaptive everyday functioning. Their heterogeneity in ongoing use of illicit substances will enable us to examine relationships between inferencing performance and treatment response.
Anosmia, dysosmia, or hyposmia (poor olfactory function), to be assessed via Sniffin Sticks threshold test \<4 or via Sniffin Sticks odor identification test \<10.
History of any neurological condition resulting in inability to perform study task. Examples include but not limited to degenerative processes of the CNS (Parkinson disease, Alzheimer disease); other neurologic diseases (Huntington disease, multiple sclerosis, other motor-neuron diseases); inflammatory conditions (sarcoidosis, Wegener granulomatosis); or significant cerebrovascular disease including (but not limited to) epilepsy, stroke, or meningitis; traumatic brain injury (TBI) or major head trauma with sustained loss of consciousness (\>30 min). To be assessed by history and physical and evaluation to sign screening consent. Eligibility will be determined based on MAI review of participants ability to perform study task. MAI will consider but is not limited to H and P results for mental status exam, language exam, and attention span exam. Rationale: any of these could impair task performance.
History of current (past 12 months) uncontrolled DSM-5 major psychiatric disorder including major affective disorder, obsessive-compulsive disorder, schizophrenia, and PTSD. (Candidates will not be excluded for a history of major psychiatric disorder that is now being successfully treated.) To be assessed by MINI or SCID interview. Rationale: could impair task performance.
History of anaphylaxis due to, e.g., significant asthma, food or non-food allergy, or intolerance to odors (including latex, detergents, soaps, etc.). To be assessed by history and physical. Rationale: could make odorant exposure risky.
Current use of medications or substances that affect alertness and that cannot be withheld on the morning of the study visit (e.g., barbiturates, benzodiazepines, cannabinoids, chloral hydrate, haloperidol, lithium, carbamazepine, phenytoin, etc.). To be assessed by history and physical. Whether candidate will be requested to withhold any medication will be determined based on MAI judgment. Additionally, if participant has a BrAC \>0.08, MAI will use clinical judgement to determine if participant should be rescheduled. Rationale: could impair task performance.
For women: pregnancy. To be assessed by history and physical and by urine testing. Rationale: Could affect task performance-physiological and hormonal changes during pregnancy influence rhinological function.
Any other medical illness or condition that in the judgment of the investigators is incompatible with study participation.
History of a substance-use disorder (except nicotine, for matching purposes), or current use of any drug for nonmedical purposes. Controls, who cannot have a history of OUD, will be assessed by their medical history and physical examination for the presence of any signs or symptoms consistent with opioid withdrawal. Any Control with any sign or symptom consistent with opioid withdrawal will be evaluated by the MAI to rule out opioid withdrawal if possible.
Urine positive for any illicit drug. Rationale: Controls should have no drug use. A UDS that is positive for a prescribed medication that the MAI has determined is not due to illicit drug use will not be exclusionary.
Urine positive for any illicit drug. Rationale: Abstinent OUD group should have no drug use in the last 3 weeks which would include the several-day time frame to which urine screens are sensitive. A UDS that is positive for a prescribed medication that the MAI has determined is not due to illicit drug use will not be exclusionary.
Current signs or symptoms of opioid withdrawal. These will be assessed in the Abstinent group via the Clinical Opioid Withdrawal Scale (COWS) and the Subjective Opioid Withdrawal Scale (SOWS).
Urine negative for opioid agonist that the participant is taking as part of their OUD treatment. Rationale: In-treatment OUD group should be in treatment. A negative test suggests the participant is not adhering to their treatment plan. In-treatment OUD participants may test positive for other substances as well as their opioid agonist because they may have ongoing illicit drug use.
What this trial measures
- Outcome inferencing in the probe testDuring task
Percentage of trials with cues A and C in which the participant predicts any odor (sweet or savory), regardless of whether the prediction is correct.