A Study of Taste- and Olfactory-Evoked Potentials in Patients With Visual Impairment: Taste, Smell, and Vision
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Taste and smell evaluation, Recording of evoked potentials (EP).
- Who it may be relevant to
- Registry conditions: Central Visual Impairment, Peripherical Visual Impairment, Macular Retinal Dystrophy, Peripherical Macular Dystrophy. Basic parameters: 18 years — 60 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- France
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Overview
Visual impairment, whether central or peripheral, may influence the plasticity of other sensory modalities, such as taste and smell. Taste-evoked potentials (TEPs) and smell-evoked potentials (SEPs)-methods for analyzing brain activity in response to taste and smell stimuli-allow for the objective assessment of these interactions. This approach has already demonstrated its value in the study of cognitive disorders. This study aims to demonstrate an enhancement of taste and smell capabilities that could compensate for specific visual impairments, particularly in situations involving food choices.
Interventions
- Other Taste and smell evaluation
Determination of taste and smell ability scores using standardized methods (ETOC and Taste Strips) - Other Recording of evoked potentials (EP)
A recording of gustatory evoked potentials (GEP) and olfactory evoked potentials (OEP) in response to stimuli consisting of sucrose solution, vanillin, and a combination of the two.
Primary outcome measures
- Average latency of PEG (Taste-Evoked Potentials) peaks [Time frame: At the baseline]
- Average amplitude of PEG (Taste-Evoked Potentials) peaks [Time frame: At the baseline]
Eligibility criteria
Inclusion criteria
- Adult: ≥ 18 years and ≤ 60 years
- Individual who has given oral consent
- Individual who has been fasting (no food, drink, or tobacco) for at least 1 hour prior to PEG and PEO measurement
- No cognitive complaints and normal neurological examination.
- Group of patients with visual impairment:
A. Central: documented bilateral macular dystrophy (e.g., Stargardt disease, Best disease) with confirmed central scotoma (CV 24.2, 10.2, or 30.2).
B. Peripheral: documented bilateral peripheral retinal dystrophy with confirmed peripheral involvement (CV 30-2 or 24-2).
- Control group: a person with normal vision and no known ophthalmological abnormalities (normal visual acuity and fundus examination) who is precisely matched by sex and smoking status (former smoker who has quit vs. nonsmoker), and approximately matched by age (± 5 years) to a visually impaired participant included in the study.
Exclusion criteria
For this group: patients with visual impairments:
- Individuals who are not enrolled in or eligible for a social security program
- Individuals subject to a legal protective measure (guardianship, conservatorship)
- Individuals subject to judicial safeguard measures
- Adults who are legally incapacitated or unable to give informed consent
- Documented COVID-19 infection within the 6 months prior to enrollment
- Active smokers (≥1 cigarette per day) or users of any other inhaled substances (water pipe, cannabis, etc.)
- Participants following a sugar-free diet
- Participants with diabetes, of any type
- Participants taking medication (ongoing during the study) that interferes with taste perception • Pregnant or breastfeeding women
- Individuals with neurodegenerative diseases (Parkinson's, Alzheimer's)
- Individuals with braids, dreadlocks, or any other hairstyle that prevents electrodes from being placed in sufficiently precise locations on the scalp.
- Overweight subjects with a BMI ≥ 35 kg/m²
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- Non-randomized
- Model
- Parallel assignment
- Masking
- Open label
- Primary purpose
- Basic science
Study locations
France · 1 center
- Chu Dijon Bourgogne — Dijon
Identifiers
NCT: NCT07707219 · GABRIELLE 2026