Processing of nociceptive input from posterior to anterior insula in humans

• Published in: Human brain mapping Vol. 35; no. 11; pp. 5486 - 5499
• Main Authors: Frot, Maud, Faillenot, Isabelle, Mauguière, François
• Format: Journal Article
• Language: English
• Published: New York, NY Blackwell Publishing Ltd 01.11.2014; Wiley-Liss; John Wiley & Sons, Inc; Wiley; John Wiley and Sons Inc
• Subjects: Adolescent; Adult; Biological and medical sciences; Brain Mapping; Cerebral Angiography; Cerebral Cortex; Cerebral Cortex - diagnostic imaging; Cerebral Cortex - physiology; Electrodes, Implanted; Evoked Potentials; Evoked Potentials - physiology; Female; Functional Laterality; Fundamental and applied biological sciences. Psychology; Humans; insula; intracerebral recordings; Investigative techniques, diagnostic techniques (general aspects); laser-evoked potentials; Lasers; Lasers - adverse effects; Life Sciences; Male; Medical sciences; Middle Aged; Nerve Net; Nervous system; Neurons and Cognition; Nociception; Nociception - physiology; pain; Personality. Affectivity; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Sexuality. Sexual behavior; Young Adult; Human; Nervous system diseases; laser-evoked potentials; Radiodiagnosis; Central nervous system; Electrophysiology; Intracerebral; insula; Encephalon; intracerebral recordings; Pain; Evoked potential; Laser; humans; pain
• ISSN: 1065-9471; 1097-0193; 1097-0193
• DOI: 10.1002/hbm.22565

Previous brain imaging studies have shown robust activations in the insula during nociceptive stimulation. Most activations involve the posterior insular cortex but they can cover all insular gyri in some fMRI studies. However, little is known about the timing of activations across the different insular sub‐regions. We report on the distribution of intracerebrally recorded nociceptive laser evoked potentials (LEPs) acquired from the full extent of the insula in 44 epileptic patients. Our study shows that both posterior and anterior subdivisions of the insular cortex respond to a nociceptive heat stimulus within a 200–400 ms latency range. This nociceptive cortical potential occurs firstly, and is larger, in the posterior granular insular cortex. The presence of phase reversals in LEP components in both posterior and anterior insular regions suggests activation of distinct, presumably functionally separate, sources in the posterior and anterior parts of the insula. Our results suggest that nociceptive input is first processed in the posterior insula, where it is known to be coded in terms of intensity and anatomical location, and then conveyed to the anterior insula, where the emotional reaction to pain is elaborated. Hum Brain Mapp 35:5486–5499, 2014. © 2014 Wiley Periodicals, Inc.