Age-related differences in electrophysiological correlates of visuospatial reorientation

Abstract

Spatial navigation abilities decline with age. Recent studies revealed a specific impairment in landmark-based reorientation, linked to changes in scene-selective brain regions activity. While fMRI studies suggest that these cortical modulations might be compensatory, a more precise investigation of the brain dynamics associated with visuospatial processing is warranted. We analyzed Event-Related Potentials and Event-Related Spectral Perturbations recorded from electrodes over scene-selective regions. 28 young adults and 28 older adults completed a desktop-based reorientation task using landmarks. Our findings show poorer reorientation performance among older adults. Signatures of age-related modulation of EEG activity imputable to scene-selective regions were predominantly observed within the right hemisphere. EEG analysis disclosed a tripartite worsening of scene processing accounting for older adults difficulties. Firstly, a delayed and reduced P1 component likely reflects a slower and less efficient stimulus discrimination. Secondly, an increased N1 amplitude and theta-band activity suggest a higher demand on cognitive resources associated with more effortful processing of visuospatial information. Thirdly, a decreased P2 amplitude may imply deficient attentional mechanisms to select task-relevant stimuli.