Cargando…

Cortical Activation Changes during Repeated Laser Stimulation: A Magnetoencephalographic Study

Repeated warm laser stimuli produce a progressive increase of the sensation of warmth and heat and eventually that of a burning pain. The pain resulting from repetitive warm stimuli is mediated by summated C fibre responses. To shed more light on the cortical changes associated with pain during repe...

Descripción completa

Detalles Bibliográficos
Autores principales: Stancak, Andrej, Alghamdi, Jamaan, Nurmikko, Turo J.
Formato: Texto
Lenguaje:English
Publicado: Public Library of Science 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3091873/
https://www.ncbi.nlm.nih.gov/pubmed/21572954
http://dx.doi.org/10.1371/journal.pone.0019744
_version_ 1782203339094622208
author Stancak, Andrej
Alghamdi, Jamaan
Nurmikko, Turo J.
author_facet Stancak, Andrej
Alghamdi, Jamaan
Nurmikko, Turo J.
author_sort Stancak, Andrej
collection PubMed
description Repeated warm laser stimuli produce a progressive increase of the sensation of warmth and heat and eventually that of a burning pain. The pain resulting from repetitive warm stimuli is mediated by summated C fibre responses. To shed more light on the cortical changes associated with pain during repeated subnoxious warm stimution, we analysed magnetoencephalographic (MEG) evoked fields in eleven subjects during application of repetitive warm laser stimuli to the dorsum of the right hand. One set of stimuli encompassed 10 laser pulses occurring at 2.5 s intervals. Parameters of laser stimulation were optimised to elicit a pleasant warm sensation upon a single stimulus with a rise of skin temperature after repeated stimulation not exceeding the threshold of C mechano-heat fibres. Subjects reported a progressive increase of the intensity of heat and burning pain during repeated laser stimulation in spite of only mild (4.8°C) increase of skin temperature from the first stimulus to the tenth stimulus. The mean reaction time, evaluated in six subjects, was 1.33 s, confirming involvement of C fibres. The neuromagnetic fields were modelled by five equivalent source dipoles located in the occipital cortex, cerebellum, posterior cingulate cortex, and left and right operculo-insular cortex. The only component showing statistically significant changes during repetitive laser stimulation was the late component of the contralateral operculo-insular source peaking at 1.05 s after stimulus onset. The amplitude increases of the late component of the contralateral operculo-insular source dipole correlated with the subjects' numerical ratings of warmth and pain. Results point to a pivotal role of the contralateral operculo-insular region in processing of C-fibre mediated pain during repeated subnoxious laser stimulation.
format Text
id pubmed-3091873
institution National Center for Biotechnology Information
language English
publishDate 2011
publisher Public Library of Science
record_format MEDLINE/PubMed
spelling pubmed-30918732011-05-13 Cortical Activation Changes during Repeated Laser Stimulation: A Magnetoencephalographic Study Stancak, Andrej Alghamdi, Jamaan Nurmikko, Turo J. PLoS One Research Article Repeated warm laser stimuli produce a progressive increase of the sensation of warmth and heat and eventually that of a burning pain. The pain resulting from repetitive warm stimuli is mediated by summated C fibre responses. To shed more light on the cortical changes associated with pain during repeated subnoxious warm stimution, we analysed magnetoencephalographic (MEG) evoked fields in eleven subjects during application of repetitive warm laser stimuli to the dorsum of the right hand. One set of stimuli encompassed 10 laser pulses occurring at 2.5 s intervals. Parameters of laser stimulation were optimised to elicit a pleasant warm sensation upon a single stimulus with a rise of skin temperature after repeated stimulation not exceeding the threshold of C mechano-heat fibres. Subjects reported a progressive increase of the intensity of heat and burning pain during repeated laser stimulation in spite of only mild (4.8°C) increase of skin temperature from the first stimulus to the tenth stimulus. The mean reaction time, evaluated in six subjects, was 1.33 s, confirming involvement of C fibres. The neuromagnetic fields were modelled by five equivalent source dipoles located in the occipital cortex, cerebellum, posterior cingulate cortex, and left and right operculo-insular cortex. The only component showing statistically significant changes during repetitive laser stimulation was the late component of the contralateral operculo-insular source peaking at 1.05 s after stimulus onset. The amplitude increases of the late component of the contralateral operculo-insular source dipole correlated with the subjects' numerical ratings of warmth and pain. Results point to a pivotal role of the contralateral operculo-insular region in processing of C-fibre mediated pain during repeated subnoxious laser stimulation. Public Library of Science 2011-05-10 /pmc/articles/PMC3091873/ /pubmed/21572954 http://dx.doi.org/10.1371/journal.pone.0019744 Text en Stancak et al. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Stancak, Andrej
Alghamdi, Jamaan
Nurmikko, Turo J.
Cortical Activation Changes during Repeated Laser Stimulation: A Magnetoencephalographic Study
title Cortical Activation Changes during Repeated Laser Stimulation: A Magnetoencephalographic Study
title_full Cortical Activation Changes during Repeated Laser Stimulation: A Magnetoencephalographic Study
title_fullStr Cortical Activation Changes during Repeated Laser Stimulation: A Magnetoencephalographic Study
title_full_unstemmed Cortical Activation Changes during Repeated Laser Stimulation: A Magnetoencephalographic Study
title_short Cortical Activation Changes during Repeated Laser Stimulation: A Magnetoencephalographic Study
title_sort cortical activation changes during repeated laser stimulation: a magnetoencephalographic study
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3091873/
https://www.ncbi.nlm.nih.gov/pubmed/21572954
http://dx.doi.org/10.1371/journal.pone.0019744
work_keys_str_mv AT stancakandrej corticalactivationchangesduringrepeatedlaserstimulationamagnetoencephalographicstudy
AT alghamdijamaan corticalactivationchangesduringrepeatedlaserstimulationamagnetoencephalographicstudy
AT nurmikkoturoj corticalactivationchangesduringrepeatedlaserstimulationamagnetoencephalographicstudy