Abstract
The introduction of functional magnetic resonance imaging (fMRI) as a non-invasive imaging modality has enabled the study of human cortical processes with high spatial specificity and allowed for a direct comparison of the human and the macaque within the same modality. This presentation will focus on the phase-encoded retinotopic mapping technique, which is used to establish parcellations of cortex consisting of distinct visual areas. These parcellations may then be used to test for similarities between the cortical organizations of the two species. Results from ongoing work will be presented with regard to retinotopic organization of the areas as well as their characterizations by functional localizers and population receptive field (pRF) sizes. Recent developments in fMRI methodology, such as improved resolution and stimulus design as well as analytical pRF methods have resulted in higher quality of the retinotopic field maps and revealed visual field-map clusters as new organizational principles in the human and macaque occipital cortex. In addition, measurements of population-average neuronal properties have the potential to establish a direct link between fMRI studies in the human and single cell studies in the monkey. An inter-subject registration algorithm will be presented, which uses a spatial correlation of the retinotopic and the functional test data to directly compare the functional characteristics of a set of putative homologue areas across subjects and species. The results indicate strong similarities between twelve visual areas in occipital cortex of human and macaque in terms of topological organization, functional characteristics and pRF sizes.
Meeting abstract presented at VSS 2012