Investigating Brain Function in People With and Without Visual Snow Syndrome Using Adaptation to Visual Stimuli (VPVSS)

University of Minnesota (UMN)

Status: Enrolling

Conditions: Healthy; Visual Snow Syndrome; Migraine

Treatments: Device: Functional Magnetic Resonance Imaging (fMRI); Device: Magnetic Resonance Imaging (MRS); Behavioral: Assessments and Questionnaires; Behavioral: Visual Adaptation

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT06961864

STUDY00014113

R01EY036005 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

The goal of this study is to learn more about the brain pathways and activity involved in creating Visual Snow Syndrome (VSS). The main questions it aims to answer are:

• Does VSS arise from spontaneous activity in brain pathways?
• Where in the brain does the activity contributing to VSS arise?
• How does brain activity contribute to VSS?

Participants will:

1. Undergo assessments and questionnaires to understand visual and mental symptoms, cognitive, and sensory function.
2. Make visual judgements based on images presented to them both inside and outside a magnetic resonance imaging (MRI) machine.
3. Undergo scanning of their brain while inside of an MRI machine.

Enrollment: 100 estimated patients

Sex: All

Ages: 18 to 60 years old

Volunteers: Accepts Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria for People with Visual Snow Syndrome:

• Between the ages of 18 and 60 years old
• Normal (20/25 or better in each eye) or corrected-to-normal vision (MR-compatible glasses will be provided as needed)
• Ability to comply with study instructions
• Individuals who have a current diagnosis of VSS from a neuro-ophthalmologist or meet diagnostic criteria of VSS (experience of dynamic dots across the visual field persisting longer than 3 months and at least 2 of the following additional visual symptoms: palinopsia, entoptic phenomena, trails behind moving objects, photophobia, or nyctalopia)
• Individuals living in Minnesota within 2 hours of the study site

Inclusion Criteria for Non-snow Controls:

• Between the ages of 18 and 60 years old
• Normal (20/25 or better in each eye) or corrected-to-normal vision (MR-compatible glasses will be provided as needed)
• Ability to comply with study instructions
• Individuals living in Minnesota within 2 hours of the study site

Exclusion Criteria for People with Visual Snow Syndrome:

• Not being fluent in English or another language for which interpretation/translation services are available

• A diagnosed or self-reported intellectual disability

• Current substance dependence (besides nicotine), or drug dependence with tolerance or withdrawal within past 12 months

• Hallucinogenic substance use within the past 12 months or hallucinogenic substance use within 12 months prior to onset of VSS symptoms

• Severe central nervous system disease

• Head injury with skull fracture or loss of consciousness for more than thirty minutes

• Presence of a physical problem that would render study measures difficult or impossible to administer or interpret (e.g., visual field loss)

• Age less than 18 years or greater than 60 years

• MRI exclusions (for MR visits only):

  • Metal in the body that cannot be approved by the CMRR safety committee
  • Pregnancy
  • Conditions that affect neuro-hemodynamic coupling
  • Claustrophobia
  • Inability to lie still for at least an hour
  • Weight in excess of 440 lbs
  • CT scan exclusion only: Research-related radiation exposure within the last 12 months

• Any vision anomaly aside from VS or refractive error (e.g., strabismus/ crossed eyes, lazy eyes, color blindness)

• Current psychotic episode

Exclusion Criteria for Non-snow Controls:

• Not being fluent in English or another language for which interpretation/translation services are available

• A diagnosed or self-reported intellectual disability

• Current substance dependence (besides nicotine), or drug dependence with tolerance or withdrawal within past 12 months

• Hallucinogenic substance use within the past 12 months

• Severe central nervous system disease

• Head injury with skull fracture or loss of consciousness for more than thirty minutes

• Presence of a physical problem that would render study measures difficult or impossible to administer or interpret (e.g., visual field loss)

• Age less than 18 years or greater than 60 years

• MRI exclusions (for MR visits only):

  • Metal in the body that cannot be approved by the CMRR safety committee
  • Pregnancy
  • Conditions that affect neuro-hemodynamic coupling
  • Claustrophobia
  • Inability to lie still for at least an hour
  • Weight in excess of 440 lbs
  • CT scan exclusion only: Research-related radiation exposure within the last 12 months

• Any vision anomaly or refractive error (e.g. strabismus/ crossed eyes, lazy eyes, color blind)

• A personal history of VSS symptoms or a diagnosis with VSS

• Current psychotic episode

Trial design

Primary purpose: Basic Science

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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100 participants in 2 patient groups, including a placebo group

People with Visual Snow Syndrome

Active Comparator group

Treatment:

Behavioral: Visual Adaptation

Behavioral: Assessments and Questionnaires

Device: Magnetic Resonance Imaging (MRS)

Device: Functional Magnetic Resonance Imaging (fMRI)

Non-snow Controls

Placebo Comparator group

Treatment:

Behavioral: Visual Adaptation

Behavioral: Assessments and Questionnaires

Device: Magnetic Resonance Imaging (MRS)

Device: Functional Magnetic Resonance Imaging (fMRI)