An interventional study of MRI/ MRS (Magnetic Resonance Imaging /Magnetic Resonance Spectroscopy) in PARKINSON DISEASE (Disorder), Bipolar 1 Disorder and Obesity (BMI>30), sponsored by University Hospital, Clermont-Ferrand. Not yet recruiting at 1 site in France. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-11-06.
Sponsored by University Hospital, Clermont-Ferrand · Not applicable, Interventional, and Basic science
Compulsive eating behaviors represent a significant issue across various disorders such as Parkinson's disease, bipolar disorders, and obesity.
Despite their apparent differences, these conditions share common underlying disturbances involving the brain's reward system, particularly within dopaminergic networks.6,7 Previous neuroimaging studies have consistently reported reward system connectivity impairment associated with compulsive eating, in each of these disorders. However, few studies have simultaneously explored the neurobiological similarities and specificities of this common symptom, eating behavior, when occurring in different populations and disorders.
The Bi-POTATOS project proposes an original and innovative approach by adopting a transdiagnostic perspective, employing brain imaging and comprehensive psycho-behavioral assessments to investigate common behavioral characteristics and neural circuit alterations associated with compulsive eating across these three conditions. For the first time, this study will allow a direct comparison of the cerebral signatures linked to compulsive eating behavior, clearly distinguishing between transdiagnostic vulnerabilities and features unique to each clinical condition.
The central hypothesis is that similar dysfunctions in brain regions involved in motivation and impulsive decision-making underpin compulsive eating behaviors, irrespective of the initial diagnosis. However, the underlying pathology may modulate these mechanisms, introducing certain specificities.
By clarifying these common mechanisms, the Bi-POTATOS project will not only enhance our understanding of the neurobiological etiology of these disorders but also pave the way for innovative, targeted therapeutic interventions. This project will precisely identify whether specific neural alterations constitute a universally relevant therapeutic target, or conversely, determine which alterations necessitate tailored therapeutic strategies based on the underlying pathology.
4,573 studies on the registry are indexed under Parkinson Disease; 1,086 are open to participants now.
This study's planned enrollment of 150 is above the median of 40 across 3,353 interventional studies indexed under Parkinson Disease.
Browse Parkinson Disease studies →University Hospital, Clermont-Ferrand is the lead sponsor of 859 studies on the registry; 179 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Affiliation to the social security system
2-Specific criteria Parkinsonian patients (n=25 with CE, n=25 without CE)
Obese patients (n=25 with CE, n=25 without CE)
Bipolar patients (n=25 with CE, n=25 without CE)
Exclusion Criteria:
Pregnant women, breastfeeding women
2- Specific criteria
Parkinsonian patients:
Obese patients:
Bipolar patients:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
MMSE and MoCA
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Visit 1 : selection visit * Inform consent and participation agreement * Assessment of the disease and eating behavior disorder severity, medication taken, as well as a standard medical examination (measurement of weight, height and blood pressure) Cognitive function, impulsive trait of personality, depression, anxiety, restless legs syndrome, REM sleep behavior disorder and pain will be assessed. Visit 2 : investigational visit * MRI scan * neuropsychological assessments
Other: MRI/ MRS (Magnetic Resonance Imaging /Magnetic Resonance Spectroscopy)
Neuropsychological assessment : motor impulsivity, motor inhibition, cognitive impulsivity (Stroop); decision making in an ambiguous context (Iowa Gambling Task), time perception (delay discounting reward task) and risk taking (Balloon analog Risk task). MRI : The subjects will be scanned using a 3-Tesla MAGNETOM Vida scanner (Siemens, Erlangen, Germany) with a 64 channel head coil Dietician : 3 days food record
Also known as: Neuropsychological assessments, Dietitian
Assessment of resting state seed-based functional connectivity from the limbic striatum (seed: ventral striatum) by MRI.
MRI is a 3-Tesla MAGNETOM Vida scanner (Siemens, Erlangen, Germany) with a 64 channel head coil. The subjects were asked to hold still, with their eyes open and not to think of anything particular. Foam padding was employed to reduce head movement and earplugs were used to reduce scanner noise. The high resolution anatomical images were obtained through a T1-weighted magnetization-prepared rapid gradient echo (MPRAGE) sequence with the following parameters: repetition time (TR): 2300 ms, echo time (TE): 3.08 ms, inversion time (IT): 900 ms, flip angle (FA): 9°, matrix: 288 x 288, 176 slices, slice thickness: 1mm. Resting-state functional MRI images were obtained using an EPI sequence with the following parameters: TR: 3000ms, TE: 30ms, FA: 81°, field of view (FOV): 192 mm, 55 slices, slice thickness: 3.3 mm, gap between slices: 3.3 mm, pixel bandwidth: 2441 Hz/Pixel, number of time points: 180, acquisition duration: 9 minutes).
Time frame: At visit 2, between 1 and 12 weeks after patient enrollment
Demographical data
sex
Time frame: at visit 1, selection visit - Day 0
Demographical data
Age (year)
Time frame: at visit 1, selection visit - Day 0
Demographical data
weight (kg)
Time frame: at visit 1, selection visit - Day 0
Demographical data
size (m)
Time frame: at visit 1, selection visit - Day 0
Parkinson Disease severity
Assessment of parkinson desease with the MDS-UPDRS (Movement Disorders Society - Unified Parkinson's Disease Rating Scale ) scale, completed by the investigator.
Time frame: at visit 1, selection visit - Day 0
Bipolar Disease severity
Assessment of bipolar desease with MADRS (Montgomery-Asberg Depression Rating Scale) and YMRS (Young Mania Rating Scale) scale, completed by the investigator.
Time frame: at visit 1, selection visit - Day 0
Obesity disease severity
Obesity classification according to Health French Agency (Haute Autorité de Santé) 2022, completed by the investigator.
Time frame: at visit 1, selection visit - Day 0
Impulsive trait of Personality according the Barratt impulsiveness scale (BIS-11)
This self questionnaire is completed by the patient during the selection visit
Time frame: at visit 1, selection visit - Day 0
Eating behavior disorder severity
Self reported eating behavior disorder using 3 questionnaires (QEWP5 (Questionnaire on Eating and Weight Patterns5), DEBQ (Dutch Eating Behaviour Questionnaire) and food craving questionnaire))
Time frame: at visit 1, selection visit - Day 0
Presence of Anxiety and/or depression according the Beck depression and anxiety scale
These self questionnaires is completed by the patient during the selection visit
Time frame: at visit 1, selection visit - Day 0
Presence of restless legs syndrome according the International Restless Legs Syndrome (Rating Scale)
This questionnaire is completed by the investigator during the selection visit
Time frame: at visit 1, selection visit - Day 0
Intensity and Pain caracteristics
Patients will evaluate their pain using 2 self questionnaires (3-PDQ, BPI (Brief Pain Inventory))
Time frame: at visit 1, selection visit - Day 0
Impulsive compulsive behaviors rating scale for PD (QUIP-RS)
The QUIP-RS is a brief 28-item patient-reported or clinician-rated scale developped for measure of severity of ICDs. Each item is rated on a 5-point Likert scale assessing frequency of symptoms with a range of scores from 0 (never) to 4 (very often).
Time frame: at visit 2, between 1 and 12 weeks after selection visit
Spontaneous food intake
Patients will report thier spontaneous food intake for 3 days using a dietary data collected. Patient nutritional intakes will be analysed using Nutrilog software
Time frame: at visit 2, between 1 and 12 weeks after selection visit
Motor impulsivity (Go/No Go task)
Motor impulsivity will be assessed with the Go/No-go task. It is a simple experimental paradigm that requires participants to respond as quickly as possible (Go) to a particular class of stimuli, for example by pressing a key on a keyboard, and not to respond to other classes of stimuli (No Go). The key behaviour measured with this experiment is the participants' ability to withhold a response on No-go trials.
Time frame: at visit 2, between 1 and 12 weeks after selection visit
Motor inhibition (Stop Signal Task (SST))
The Stop Signal Task (SST) is a test that measures motor inhibition. The participant must respond quickly to Go stimuli but interrupt their response when a stop signal appears. The key index, the Stop Signal Reaction Time (SSRT), reflects the time required to stop an ongoing action. This test will be performed by neuropsychologist.
Time frame: at visit 2, between 1 and 12 weeks after selection visit
Iowa Gambling Task (IGT)
IGT assesses risk-based learning by relying on a system of rewards and punishments within a simulated context of uncertainty, representing a real-life decision-making situation. Participants choose cards from four decks, each associated with varying amounts of monetary gains and losses. Over time, advantageous decks yield higher net rewards, while disadvantageous decks lead to net losses. Performance on the task reflects an individual's capacity to balance immediate rewards against long-term outcomes, thereby providing insight into adaptive decision-making and risk evaluation processes. This test will be performed by neuropsychologist.
Time frame: at visit 2, between 1 and 12 weeks after selection visit.
Cognitive impulsivity (Stroop)
The Stroop Test is a cognitive task designed to evaluate attentional control and the ability to inhibit automatic responses when faced with conflicting information. Participants are asked to name the color of the ink in which words are printed, even when the word itself refers to a different color (e.g., GREEN printed in red ink). This requires suppressing the automatic tendency to read the word and instead focusing on the ink color. The difference in performance between congruent and incongruent conditions, known as the Stroop interference effect, is a key indicator of cognitive inhibition and executive control. This test will be performed by neuropsychologist.
Time frame: at visit 2, between 1 and 12 weeks after selection visit
Time perception (delay discounting reward task)
Participants make choices between two alternatives: a larger reward available after a delay (across seven delay intervals) and a smaller reward available immediately. The value of the immediate reward is systematically adjusted, either increasing or decreasing, in separate blocks. The task assesses preferences for immediate versus delayed gratification using two reward types: money and food. This test will be performed by neuropsychologist.
Time frame: at visit 2, between 1 and 12 weeks after selection visit
Balloon analog Risk task
Participants are given 30 balloons (by default). For each balloon, they can choose either to inflate it further or to collect their earnings. With each successful inflation, they can earn money. However, if a balloon bursts before the participant collects the potential earnings, they lose all potential gains associated with that balloon. The average number of pumps on balloons that do not burst is the primary dependent variable in this paradigm. A higher number of pumps reflects increased risk-taking behavior. This test will be performed by neuropsychologist.
Time frame: at visit 2, between 1 and 12 weeks after selection visit
Surface based (Freesurfer) and Voxel based (SPM) morphometry performed by MRI
MRI is a 3-Tesla MAGNETOM Vida scanner (Siemens, Erlangen, Germany) with a 64 channel head coil. The subjects were asked to hold still, with their eyes open and not to think of anything particular. Foam padding was employed to reduce head movement and earplugs were used to reduce scanner noise. The high resolution anatomical images were obtained through a T1-weighted magnetization-prepared rapid gradient echo (MPRAGE) sequence with the following parameters: repetition time (TR): 2300 ms, echo time (TE): 3.08 ms, inversion time (IT): 900 ms, flip angle (FA): 9°, matrix: 288 x 288, 176 slices, slice thickness: 1mm. Resting-state functional MRI images were obtained using an EPI sequence with the following parameters: TR: 3000ms, TE: 30ms, FA: 81°, field of view (FOV): 192 mm, 55 slices, slice thickness: 3.3 mm, gap between slices: 3.3 mm, pixel bandwidth: 2441 Hz/Pixel, number of time points: 180, acquisition duration: 9 minutes).
Time frame: at visit 2, between 1 and 12 weeks after selection visit
Structural connectivity (MRtrix and TRACTseg) performed by MRI
MRI is a 3-Tesla MAGNETOM Vida scanner (Siemens, Erlangen, Germany) with a 64 channel head coil. The subjects were asked to hold still, with their eyes open and not to think of anything particular. Foam padding was employed to reduce head movement and earplugs were used to reduce scanner noise. The high resolution anatomical images were obtained through a T1-weighted magnetization-prepared rapid gradient echo (MPRAGE) sequence with the following parameters: repetition time (TR): 2300 ms, echo time (TE): 3.08 ms, inversion time (IT): 900 ms, flip angle (FA): 9°, matrix: 288 x 288, 176 slices, slice thickness: 1mm. Resting-state functional MRI images were obtained using an EPI sequence with the following parameters: TR: 3000ms, TE: 30ms, FA: 81°, field of view (FOV): 192 mm, 55 slices, slice thickness: 3.3 mm, gap between slices: 3.3 mm, pixel bandwidth: 2441 Hz/Pixel, number of time points: 180, acquisition duration: 9 minutes).
Time frame: at visit 2, between 1 and 12 weeks after selection visit
Resting state seed-based functional connectivity from the limbic striatum performed by MRI
MRI is a 3-Tesla MAGNETOM Vida scanner (Siemens, Erlangen, Germany) with a 64 channel head coil. The subjects were asked to hold still, with their eyes open and not to think of anything particular. Foam padding was employed to reduce head movement and earplugs were used to reduce scanner noise. The high resolution anatomical images were obtained through a T1-weighted magnetization-prepared rapid gradient echo (MPRAGE) sequence with the following parameters: repetition time (TR): 2300 ms, echo time (TE): 3.08 ms, inversion time (IT): 900 ms, flip angle (FA): 9°, matrix: 288 x 288, 176 slices, slice thickness: 1mm. Resting-state functional MRI images were obtained using an EPI sequence with the following parameters: TR: 3000ms, TE: 30ms, FA: 81°, field of view (FOV): 192 mm, 55 slices, slice thickness: 3.3 mm, gap between slices: 3.3 mm, pixel bandwidth: 2441 Hz/Pixel, number of time points: 180, acquisition duration: 9 minutes).
Time frame: at visit 2, between 1 and 12 weeks after selection visit
Start is estimated for Dec 2026; primary completion for Jul 2029, 31 months later.
Of 1,291 non-industry interventional studies with no phase under Parkinson Disease, half reached primary completion within 24 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 44. This study's planned 31 months is above that.
Counting every sponsor, half of 1,367 studies reached it within 25 months; a quarter within 11 and three quarters within 44.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Nov 2026. You cannot join it, but the record below documents what was studied.
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