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Body awareness is constructed by signals originating from within and outside the body. How do these apparently divergent signals converge? We developed a signal detection task to study the neural convergence and divergence of interoceptive and somatosensory signals. Participants focused on either cardiac or tactile events and reported their presence or absence. Beyond some evidence of divergence, we observed a robust overlap in the pattern of activation evoked across both conditions in frontal areas including the insular cortex, as well as parietal and occipital areas, and for both attention and detection of these signals. Psycho-physiological interaction analysis revealed that right insular cortex connectivity was modulated by the conscious detection of cardiac compared to somatosensory sensations, with greater connectivity to occipito-parietal regions when attending to cardiac signals. Our findings speak in favour of the inherent convergence of bodily-related signals and move beyond the apparent antagonism between exteroception and interoception.

Rationale and Objectives This study evaluated the altered regional cerebral blood flow (rCBF) in resting state in patients with acute posttraumatic stress disorder (PTSD) 3 months after trauma. Materials and Methods The rCBF was measured in 30 patients with acute PTSD and 36 healthy controls. Results Survivors with acute PTSD showed decreased rCBF, the Clinician-Administered PTSD Scale score correlated negatively with the rCBF, and rCBF at resting state decreased in acute PTSD. Conclusions PTSD symptom severity was associated with diminished cerebral blood flow in the right insular cortex and right orbital medial frontal gyrus. The rCBF may predict PTSD symptom severity.

In this review, I provide an overall description of the findings obtained from neuroimaging studies aimed at investigating the neural substrates underpinning aesthetic experience when viewing masterpieces of Classical art. In particular, I here argue the idea that aesthetic experience is hallmarked by a hedonic response to the stimuli. This response would be triggered, according to our proposal, by integration of emotional and cognitive processes at the level of the right insular cortex and, more specifically, of its anterodorsal sector. I then discuss the recent results suggesting that the hedonic quality characterizing aesthetic experience for artworks is absent when aesthetically appraising biological non-artist stimuli.

A 43-year-old man presented to the Prince of Wales Hospital, Sydney, New South Wales, Australia, after experiencing his first tonic-clonic seizure. For the previous 2 years he had undergone gastroenterological investigation of episodes of gagging associated with hypersalivation and lachrymation, occurring three or four times per week. EEG showed epileptiform discharges in the right anterior temporal region; brain MRI revealed a lesion in the right insular cortex. Video-EEG telemetry demonstrated that the episodes of gagging were focal seizures. Antiepileptic drug therapy resulted in no further episodes occurring over the next 10 months.

Working memory (WM) for auditory information has been thought of as a unitary system, but whether WM for verbal and tonal information relies on the same or different functional neuroarchitectures has remained unknown. This fMRI study examines verbal and tonal WM in both nonmusicians (who are trained in speech, but not in music) and highly trained musicians (who are trained in both domains). The data show that core structures of WM are involved in both tonal and verbal WM (Broca's area, premotor cortex, pre‐SMA/SMA, left insular cortex, inferior parietal lobe), although with significantly different structural weightings, in both nonmusicians and musicians. Additionally, musicians activated specific subcomponents only during verbal (right insular cortex) or only during tonal WM (right globus pallidus, right caudate nucleus, and left cerebellum). These results reveal the existence of two WM systems in musicians: A phonological loop supporting rehearsal of phonological information, and a tonal loop supporting rehearsal of tonal information. Differences between groups for tonal WM, and between verbal and tonal WM within musicians, were mainly related to structures involved in controlling, programming and planning of actions, thus presumably reflecting differences in action‐related sensorimotor coding of verbal and tonal information. Hum Brain Mapp 32:771–783, 2011. © 2010 Wiley‐Liss, Inc.

A significant reduction in perfused microvasculature in right caudate nucleus and right insular cortex was demonstrated in 22 monkeys at 0.5, 4, 12, 24, and 48 hours and 2 weeks following transorbital occlusion of the right middle cerebral artery (RMCA). The microvasculature was visualized by an india ink perfusion method and subjected to morphometric analysis with a Leitz ASBA image analysis system. The reduction in number, length, and changes in diameter of the microvessels visualized with india ink are discussed.

The perception of dyspnea and pain show many similarities. Initial imaging studies suggested an important role of the insular cortex for the perception of both sensations. However, little is known about the cortical processing of dyspnea.This study investigated the influence of lesions of the insular cortex on the perception of dyspnea and pain.Dyspnea was induced by resistive loaded breathing in four patients with right-hemispheric insular cortex lesions, as assessed with computer tomography or magnetic resonance imaging, and four matched healthy control subjects. Pain was induced by a cold-pressor test. Perceived intensity and unpleasantness of both sensations were rated on visual analog scales.In contrast to healthy control subjects, patients with lesions demonstrated reduced perceptual sensitivity for dyspnea, in particular for the unpleasantness of dyspnea (P0.05). This was paralleled by reduced sensitivity for pain in patients with lesions, as reflected by smaller ratings of intensity and unpleasantness, higher sensory pain-thresholds, and, in particular, higher affect-related pain tolerance times (P0.05).The results suggest that lesions of the right insular cortex are associated with reduced sensitivity for the perception of dyspnea and pain, in particular for their perceived unpleasantness. This underlines the importance of the insular cortex for the perception of both sensations.

A 67-year-old man had repeated cerebral ischemic attacks, which resulted in a clinical picture combining paralysis of visual fixation, optic ataxia and impairment of visuospatial orientation, consistent with the definition of Balint's syndrome. Postmortem examination showed multiple lesions involving the occipital cortex of both sides and the white matter underlying the right insular cortex. EOG recording demonstrated a marked impairment of refixation saccades and saccades on verbal command. Smooth pursuit movements were completely abolished. Visual fixation was randomly achieved after many erratic exploratory movements and steadily maintained on the target (spasmodic fixation). During spasmodic fixation, EOG recording detected an ocular flicker resulting in a continuous instability of eye position. It is suggested that these findings may all be accounted for by the loss of panoramic vision due to a bilateral impairment of cortical areas 18 and 19.