Age

18–any

Sex

ALL

Healthy volunteers

Not accepted

Confirmed diagnosis of progressive Multiple Sclerosis (MS, primary or secondary) by a neurologist or an MS center
Patient-Reported Outcomes Measurement Information System (PROMIS) Depression T-scores \>55 at baseline
Ability to provide informed consent and participate in VR sessions at home
For Some Participants (Groups 1 and 2) currently receiving antidepressant or psychotherapy treatments (Selective Serotonin Reuptake Inhibitors (SSRIs), Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs), or psychotherapy) for the management of depression

Severe cognitive impairments or visual deficits that may interfere with VR use, including contraindications like agoraphobia, claustrophobia, or motion sickness
Current participation in other clinical trials targeting depression
Severe psychiatric conditions that require hospitalization, or suicidal ideation, passive or active, psychosis, or active substance and alcohol abuse (score greater than 1 on CAGE (Cut down, Annoyed, Guilty, Eye-opener) Adapted to Include Drugs (CAGE-AID))
Another neurological or autoimmune disease per protocol
Participants that require vision correction, unless that vision correction is mild (± 1), or the participant has prescription contact lenses.

Bringing the Outdoors In: Virtual Nature Walks for Depression in Multiple Sclerosis (MS) Patients