Insula Connections With the Parieto-Frontal Circuit for Generating Arm Actions in Humans and Macaque Monkeys

• Published in: Cerebral cortex (New York, N.Y. 1991) Vol. 29; no. 5; pp. 2140 - 2147
• Main Authors: Di Cesare, G, Pinardi, C, Carapelli, C, Caruana, F, Marchi, M, Gerbella, M, Rizzolatti, G
• Format: Journal Article
• Language: English
• Published: United States Oxford University Press 01-05-2019
• Subjects: grasping circuit; dorso-central insular cortex; MRI tractography
• ISSN: 1047-3211; 1460-2199
• DOI: 10.1093/cercor/bhy095

Abstract
It has been recently found that the human dorso-central insular cortex contributes to the execution and recognition of the affective component of hand actions, most likely through modulation of the activity of the parieto-frontal circuits. While the anatomical connections between the hand representation of the insula and, the parietal and frontal regions controlling reaching/grasping actions is well assessed in the monkey, it is unknown the existence of a homolog circuit in humans. In the present study, we performed a multifiber tractography investigation to trace the tracts possibly connecting the insula to the parieto-frontal circuits by locating seeds in the parietal, premotor, and prefrontal nodes of the reaching/grasping network, in both humans and monkeys. Results showed that, in both species, the insula is connected with the cortical action execution/recognition circuit by similar white matter tracts, running in parallel to the third branch of the superior longitudinal fasciculus and the anterior segment of the arcuate fasciculus.