The insular cortex

Whether you see the person you are in love with, try to listen to your own heartbeat, suffer from a headache, or crave for a chocolate cookie, one part of your brain is sure to increase its activity strongly: the insular cortex. The insular cortex, or ‘insula’ for short, is part of the cerebral cortex. J.C. Reil, a German neurologist, first named this brain structure in the early 19th century. Subsequent research findings have implicated the insula in an overwhelming variety of functions ranging from sensory processing to representing feelings and emotions, autonomical and motor control, risk prediction and decision-making, bodily- and self-awareness, and complex social functions like empathy. How is one single brain area involved in so many different tasks? Is the insula comprised of several functional regions? How are these related? And, are there any common themes underlying the apparently so heterogeneous roles of the insula? The insular cortex is a highly associative brain region involved in the processing of feelings and emotions, and in guiding flexible behaviors. In this Primer, Nadine Gogolla describes basic motifs of insula functions and suggests that the rodent model may provide a powerful tool to study the basic neuronal underpinnings of this complex brain region.