Structural Connectivity of the Insula
The insula is a multimodal structure located underneath the Sylvian fissure and is considered as a paralimbic region. It is widely connected to several cortical areas in the frontal, temporal, parietal, and occipital lobes, as well as subcortical regions such as the thalamus, amygdala, and hippocampus. The insular sulcus divides it into an anterior and a posterior part. Its strategic location and extensive connectivity subserves a wide range of functions. Among them are the processing of visceral, somatosensory, gustatory, olfactory, and auditory inputs, language, motivation, awareness, craving, addiction, and emotions such as empathy and disgust. The implication of the insula in these numerous functions makes it a staple relay structure of the brain. In this chapter, we will examine the anatomy and structural connectivity profile of the insula, based on tract-tracing studies in nonhuman primates as well as diffusion tractography and postmortem studies in humans.
KeywordsInsula Insular Cortex Connectivity Cortical Structural Connections Structures
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