Scene-selective regions encode the vertical position of navigationally relevant information in young and older adulthood

Abstract

Position within the environment influences the navigational relevance of objects. However, the possibility that vertical position represents a central object property has yet to be explored. Considering that the upper and lower visual fields afford distinct types of visual cues and that scene-selective regions exhibit retinotopic biases, it is of interest to elucidate whether the vertical location of visual information modulates neural activity in these high-level visual areas. The occipital place area (OPA), parahippocampal place area (PPA) and medial place area (MPA) demonstrate biases for the contralateral lower visual field, contralateral upper visual field, and contralateral hemifield, respectively. Interesting insights could also be gained from studying older adulthood as recent work points towards an age-related preference for the lower visual field. In the present study, young and older participants learned the position of a goal in a virtual environment that manipulated two variables: the vertical position of navigationally-relevant objects and the presence of non-relevant objects. Results revealed that all three scene-selective regions parsed the vertical position of useful objects independently of their subtending retinotopic biases. It therefore appears that representations in the higher-level visual system combined information about vertical position and navigational value for wayfinding purposes. This property was maintained in healthy ageing emphasizing the enduring significance of visual processing along the vertical dimension for spatial navigation abilities across the lifespan.