CCN meeting | Mitchell Valdes-Sosa, Cuban Center for Neuroscience, Cuba

07-03-2018 from 15:00 to 16:00
Henri Dunantlaan 2, room 4.3 (4C)
Add to my calendar

Combining Multivariate Pattern Analysis and Functional Connectivity at the voxel level: application to the study of visual attention

We still do not understand adequately the neural basis of visual selective attention despite a wealth of studies using neural unit recordings in animals and functional neuroimaging in humans. One poorly understood area is how we focus attention at selected levels of hierarchically organized objects. It is not clear which cortical areas carry the abstract information about spatial scale (invariant to shape)  necessary to guide attention to global aspects or to local elements, and how they interact with cortical carrying abstract information about shape (invariant to scale) necessary for object recognition. We applied cross-classification MVPA in a searchlight analysis and found that information about abstract scale and abstract shape were preferentially carried by distinct ventral occipital temporal areas separated by the mid-fusiform sulci, with the former medial and the latter lateral to this landmark. Studies of the voxel connective fields in these areas, based on the background connective showed that important shifts of field eccentricity and size clearly seen in the lateral “shape” area, but were less prominent in the medial “scale” area. Connectivity between the two (despite their close spatial proximity) was negligible. This suggests specific neural mechanisms for top-down control of attention to hierarchical level, and indicates that in order to understand better brain function, we must move away from studying average activations or connections patterns of large regions of interest, and examined finely grained activity and connectivity patterns.