Title
A spatiotemporal signature of cortical pain relief by tactile stimulation: An MEG study.
Abstract
Recently, the cortical mechanisms of tactile-induced analgesia have been investigated; however, spatiotemporal characteristics have not been fully elucidated. The insular–opercular region integrates multiple sensory inputs, and nociceptive modulation by other sensory inputs occurs in this area. In this study, we focused on the insular–opercular region to characterize the spatiotemporal signature of tactile-induced analgesia using magnetoencephalography in 11 healthy subjects. Aδ (intra-epidermal electrical stimulation) inputs were modified by Aβ (mechanical tactile stimulation) selective stimulation, either independently or concurrently, to the right forearm. The optimal inter-stimulus interval (ISI) for cortical level modulation was determined after comparing the 40-, 60-, and 80-ms ISI conditions, and the calculated cortical arrival time difference between Aδ and Aβ inputs. Subsequently, we adopted a 60-ms ISI for cortical modulation and a 0-ms ISI for spinal level modulation. Source localization using minimum norm estimates demonstrated that pain-related activity was located in the posterior insula, whereas tactile-related activity was estimated in the parietal operculum. We also found significant inhibition of pain-related activity in the posterior insula due to cortical modulation. In contrast, spinal modulation was observed both in the posterior insula and parietal operculum. Subjective pain, as evaluated by the visual analog scale, also showed significant reduction in both conditions. Therefore, our results demonstrated that the multisensory integration within the posterior insula plays a key role in tactile-induced analgesia.
Year
DOI
Venue
2016
10.1016/j.neuroimage.2016.01.065
NeuroImage
Keywords
Field
DocType
Intra-epidermal electrical stimulation,Mechanical tactile stimulation,Tactile-induced analgesia,Insular–opercular region,Magnetoencephalography
Insula,Brain mapping,Neuroscience,Multisensory integration,Psychology,Nociception,Sensory system,Magnetoencephalography,Sensory stimulation therapy,Stimulation
Journal
Volume
ISSN
Citations 
130
1053-8119
0
PageRank 
References 
Authors
0.34
7
6
Name
Order
Citations
PageRank
Mariko Hayamizu100.34
Koichi Hagiwara2252.05
Naruhito Hironaga341.48
Katsuya Ogata4283.65
Sumio Hoka500.34
Shozo Tobimatsu6164.97