Presenting at ECVP
Making sense of noisy visual input: interactions between lateral and medial ventral brain regions associated with object recognition
Barbara Nordhjem, Anne Marthe Meppelink, Branislava Ćurčić-Blake, Remco Renken, Bauke M. de Jong, Klaus L. Leenders, Teus van Laar, Frans W. Cornelissen
The ventral visual pathway has been implicated in conscious recognition of objects. Earlier studies have pointed towards the lateral section of the ventral cortex as an essential region for object recognition, but recent work also implies a function for more medial sections. The interactions between these different sections within the ventral pathway are not well understood.
Data were collected in an fMRI study where thirteen subjects recognized images of objects and animals that were gradually revealed from noise [Meppelink et al, 2009, Brain, 132 (11), 2980-2993]. Here we investigated effective connectivity within the ventral pathway with dynamic causal modeling (DCM) and Bayesian model selection. We defined bilateral intrinsic connections in a network comprising the primary visual cortex (V1), lingual gyrus (LG) and the lateral occipital cortex (LO), and studied the modulatory effect of object recognition on this network. We found that object recognition modulated both feed-forward connectivity from V1 to LG and LO as well as bilateral connectivity between LG and LO. Our results suggest that object recognition is the result of an interplay between areas in the medial and lateral sections of the ventral stream.