Toward clinical implementation of free visual exploration in neglect diagnostics: Reference data and psychometric properties across adulthood.

Abstract

Neglect after stroke is a common cognitive deficit and an important predictor of poor functional recovery. Video-oculography during Free Visual Exploration (FVE) has emerged as a sensitive and reliable method for detecting neglect and assessing overt visuo-spatial attention. However, broader clinical application remains limited by the absence of clinically usable reference standards and uncertainty regarding age effects. To address this gap, we established the reference framework required for clinically interpretable use of FVE across adulthood and clarified which FVE measures can be interpreted independently of age and which require age-aware interpretation. Data from 84 neurotypical participants aged 20-89 years were analysed using two FVE versions. Mean gaze position, the primary neglect marker, was not affected by age. Fixation duration and cumulative fixation duration likewise showed no age effect. Predefined neglect cut-offs retained high specificity (>95%). Older participants showed reduced mean number of fixations, as well as a reduced peripheral exploration, reflected by smaller exploration range and exploration area, indicating that these variables require age-aware interpretation. Test-retest reliability was good across variables, supporting repeated use over time. These findings support broader clinical implementation of FVE as a brief, efficient, and ecologically relevant tool for neglect assessment in clinical practice and research.