Schedule of Events | Symposia

Defining a Photophobia Connectome: Abnormal Visual and Pain Network Activity Associated with Light Sensitivity in a Multimorbid Veteran Sample

Poster Session D - Monday, March 31, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Caroline Carrozzini^1,2,3, Madeleine Nowak^2,3,4, Jennifer A. Gustafson^1,2,5,6,7, David H. Salat^2,3,7,8, Catherine B. Fortier^2,7, William P. Milberg^2,7, Francesca C. Fortenbaugh^1,2,3,6,7; ¹Cognitive & Sensory Systems Laboratory (CASSL), VA Boston Healthcare System, ²Translational Research Center for Traumatic Brain Injury and Stress Disorders (TRACTS), VA Boston Healthcare System, ³Neuroimaging Research for Veterans Center (NeRVe), VA Boston Healthcare System, ⁴Department of Psychiatry, Boston University Chobanian & Avedisian School of Medicine , ⁵Optometry Clinic, VA Boston Healthcare System, ⁶New England College of Optometry , ⁷Department of Psychiatry, Harvard Medical School, ⁸Anthinoula A. Martinos Center for Biomedical Imaging

Photophobia, or abnormal light sensitivity, is a prevalent disorder primarily assessed through subjective self-report measures. It has frequently been linked to chronic pain and neuropsychiatric comorbidities, including PTSD, depression, and anxiety. While animal models have primarily focused on disrupted signal processing in early sensory nuclei (i.e., trigeminal pathways), the association between photophobia and psychiatric disorders suggests that cortical networks may play a critical role in chronic photophobia. This study investigated the relationship between self-reported photosensitivity and resting-state function connectivity (rs-fMRI) to identify distinct neural patterns associated with the condition. Data were analyzed from 204 post-9/11 Veterans in the Translational Research Center for TBI & Stress Disorders longitudinal cohort study. Participants were categorized as having photosensitivity (n=61) or not having photosensitivity (n=143) via self-report on item seven of the Neurobehavioral Symptom Inventory. Demographic, psychiatric, and clinical data were evaluated in conjunction with rs-fMRI scans. A hierarchical feature selection process identified a 7-feature connectome with maximum predictive accuracy for photosensitivity status (accuracy=74.02%, sensitivity=68.85%, specificity=76.22%, p < 0.001). Cross-validated discriminant analyses confirmed the specificity of these features to photosensitivity, independent of psychiatric or behavioral comorbidities. This study identified distinct functional connectivity patterns associated with photophobia, revealing a crucial neural link between visual processing and pain pathways. Findings suggest that photophobia is not exclusively a symptom of behavioral or psychiatric disorders but represents a unique neurophysiological process triggered by multiple interacting factors. These results suggest that alternative therapeutic approaches, such as transcranial magnetic stimulation, may be beneficial to effectively target photophobia in some patients.

Topic Area: METHODS: Neuroimaging