Functional Connectivity and Role of the Insular Cortex

The insular cortex is a multifaceted hub that integrates visceral, sensory and affective information to support homeostatic regulation, emotional awareness and high-order cognitive processes. Structurally, it is anchored by diverse white-matter pathways linking its anterior and posterior subdivisions to limbic, paralimbic and neocortical regions. Functionally, it participates in large-scale networks—most notably the salience network—by dynamically coordinating activity between default-mode and executive control circuits. Through interoceptive signalling, the insula generates subjective feelings that inform decision making and adaptive behaviour. Its heterogeneous cytoarchitecture, from granular posterior territories to agranular anterior sectors, underlies a rostrocaudal functional gradient spanning sensorimotor integration, affective evaluation and autonomous regulation.

Research from Nature Portfolio

Advanced tractography studies have delineated precise subcortical projections of insular subregions, revealing that dorsal and ventral insular gyri preferentially connect with thalamic, limbic and basal-ganglia nuclei. This topographical mapping clarifies how distinct insular zones contribute to sensory, emotional and reward-related processing through targeted subcortical pathways. In parallel, single-cell transcriptomic analyses have characterised von Economo neurons as a specialised class of extratelencephalic excitatory cells in layer 5 of the frontoinsula. These neurons exhibit unique gene-expression profiles and membrane properties that support rapid long-range signalling. Together, these findings bridge molecular identity and macroscopic connectivity, offering insight into how insular microstructure underpins its role in salience detection and behavioural adaptation.

Functional Connectivity and Role of the Insular Cortex publication trend

The graph below shows the total number of articles in functional connectivity and role of the insular cortex across all publications each year (not limited to Nature Index journals).

Technical terms

Functional connectivity: Statistical dependencies between spatially separated brain regions reflecting coordinated neuronal activity.

Structural connectivity: Anatomical white-matter pathways that physically link distinct neural territories.

Salience network: Large-scale brain network centred on the anterior insula and anterior cingulate cortex, involved in detecting and filtering behaviourally relevant stimuli.

Interoception: The sensing and integration of internal bodily states, such as heartbeat, respiration and visceral signals.

von Economo neurons: Large spindle-shaped layer-5 neurons in the frontoinsula and anterior cingulate cortex, specialised for rapid long-distance signalling.

References

1. Probabilistic tractography recovers a rostrocaudal trajectory of connectivity variability in the human insular cortex. Human Brain Mapping (2011).
2. The Organization of the Primate Insular Cortex. Frontiers in Neuroanatomy (2019).
3. Anterior insular cortex and emotional awareness. The Journal of Comparative Neurology (2013).
4. Subcortical structural connectivity of insular subregions. Scientific Reports (2018).
5. Transcriptomic evidence that von Economo neurons are regionally specialized extratelencephalic-projecting excitatory neurons. Nature Communications (2020).
6. Anterior insula as a gatekeeper of executive control. Neuroscience & Biobehavioral Reviews (2022).
7. The role of the salience network in cognitive and affective deficits. Frontiers in Human Neuroscience (2023).
8. Microstructural organization of human insula is linked to its macrofunctional circuitry and predicts cognitive control. eLife (2020).