On the robustness of consciousness neural correlates

Abstract

According to dynamic core hypothesis, integration and di erentiation are main properties of consciousness. Hence, we expected that the consciousness neuronal correlate covers these properties in structural level. These properties could be captured in smallworldness properties, i.e. high clustering coe cient and low path-length. Thalamocortical (TC) loop and cortex are two main candidates for Neural Correlates of Consciousness (NCC). We studied small-worldness in these systems. For this purpose, we calculated clustering coe cients, characteristic path lengths and their robustness against lesions. We simulated lesions in two ways: eliminating connections, and deleting nodes. We used anatomical connections of TC and cortex of macaque from the CoCoMac neuroinformatic database. Our results show that: 1) Lesions causes an increase in path length and decrease in clustering coe cient which cause the destruction of the integration and segregation capabilities of brain network; 2) Deleting the connections is more destructive than deletingthe nodes; 3) During high levels of lesions, the thalamo-cortical connections are more important than cortico-cortical connections in the sense of clustering coe cient. In terms ofpath-length, during high levels of nodes' lesions, the thalamo-cortical connections are more important than cortico-cortical connections, while during edges' lesions cortico-cortical connections are more important than thalamo-cortical connections