Fig. 3

Seed-to-voxel analysis using the first derivative time series as a seed signal. (A) Voxels positively correlated across all participants are shown in red, while those negatively correlated are shown in blue. (B) Voxels more correlated in older participants (> 57 years) are shown in red, while those more correlated in younger participants (< 57 years) are shown in blue. All clusters identified were less correlated with the first derivative of pupil diameter in older participants (> 57 years)