Mapping optimistic and pessimistic dopamine signals in health and Parkinson's disease

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This observational project uses a reward-learning task inside an MRI to measure brain activity in the ventral tegmental area and basal ganglia in people with Parkinson's disease and healthy participants. Researchers will apply computational reinforcement-learning models, including distributional RL concepts, to derive maps of optimistic and pessimistic reward prediction signals. They will compare the distribution and topography of these signals between groups to test whether pessimistic-type signals are selectively reduced in Parkinson's disease. The work combines high-resolution functional imaging with model-based analysis to link cellular-level findings from animal work to human brain function.

Why it matters

Who can join: the full rules

PD PATIENTS:

Inclusion Criteria:

* At least 35 years of age.
* Clinically established or probable PD according to the Movement Disorder Society Clinical Diagnostic Criteria for Parkinson's Disease
* Akinetic-rigid type PD
* Stable antiparkinsonian medicine for 4 weeks without major side effects such as dyskinesia or on-off periods.
* Signed informed consent.

Exclusion Criteria:

* Female participants of childbearing age must not be pregnant, and they must use contraception.
* Breastfeeding.
* History of other neurologic or psychiatric disease other than depression.
* Claustrophobia, pacemakers, implanted electronic devices, metal in the body, or other contraindications for MR scans.
* Patients receiving advanced PD treatment such as duodopa pump or apomorphine pen
* Regular intake of antipsychotics and GABAergic medications (such as pregabalin and gabapentine).
* Severe depression (MDI score \> 29).
* Refuse to be informed about new health-related findings that might appear through participation.

HEALTHY CONTROLS:

Inclusion criteria:

* At least 35 years of age.
* Signed informed consent.

Exclusion criteria:

* Female participants of childbearing age must not be pregnant, and they must use contraception.
* Breastfeeding.
* History of neurologic or psychiatric disease other than depression.
* Claustrophobia, pacemakers, implanted electronic devices, metal in the body, or other contraindications for MR scans.
* Regular intake of antipsychotics and GABAergic medications (such as pregabalin and gabapentine).
* Severe depression (MDI score \> 29).
* Refuse to be informed about new health-related information and accidental health-related findings that might appear through participation.

Where it's running

• Danish Research Centre for Magnetic Resonance (DRCMR), Hvidovre Hospital
  Hvidovre, Denmark Recruiting

Study contacts

• Principal investigator: David Meder, PhD — Danish Research Centre for Magnetic Resonance (DRCMR), Hvidovre Hospital
• Study coordinator: David Meder, PhD
• Email: davidm@drcmr.dk
• Phone: 004529892696

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.