Séminaire COSY: "The posterior insula is not a primary cortex for pain."


Le Dr. Giulia LIBERATI (IoNS/COSY) présentera le 4 mars un séminaire sur les liens entre l'insula postérieure et la douleur.


Ce séminaire (invitation) se déroulera dans la salle de séminaire Martin V 42B, de 12h30 à 13h30 sur le campus de Louvain-en-Woluwe (UCL) et s'inscrit dans le cadre du cycle de séminaires 2015-2016 organisé par le pôle COSY.

ABSTRACT : A widely accepted textbook notion is that the insula, especially its posterior portion, plays a specific role in the perception of pain. However, this interpretation is largely based on reverse inference, and a specific involvement of the insula for pain has never been demonstrated. In this seminar, I will present recent findings obtained from intracerebral depth electrodes implanted in the human anterior and posterior insula. First, I will show that transient nociceptive and non-nociceptive vibrotactile, auditory, and visual stimuli all elicit consistent local field potentials (LFPs) in both the anterior and posterior insula, with matching spatial distributions. These nociceptive and non-nociceptive LFPs can be largely explained by multimodal neural activity unrelated to pain and nociception. This finding confutes the widespread assumption that LFPs recorded from the human insula are a signature for pain perception and its modulation.Second, I will present data showing that, for both nociceptive and non-nociceptive modalities, stimulus repetition – and therefore the reduction of stimulus salience – has no effect on the intensity of perception, but is associated with a significant decrease of LFP amplitude. This finding suggests that LFPs elicited in the human insula by transient nociceptive and non-nociceptive stimuli reflect multimodal activity involved in detecting, orienting attention towards, and/or reacting to the occurrence of salient sensory events, regardless of the sensory modality through which these events are conveyed, and independently of perceived intensity. Finally, I will show that nociceptive stimuli, but not non-nociceptive stimuli, elicit an early-latency burst of gamma-band oscillations (GBOs) at several insular locations. These high frequency activities could reflect neural processes through which pain actually arises from nociception in the human brain.

Publié le 18 février 2016