Getting in touch: segregated somatosensory what and where pathways in humans revealed by electrical neuroimaging.

Details

Serval ID
serval:BIB_0290B4425D5C
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Getting in touch: segregated somatosensory what and where pathways in humans revealed by electrical neuroimaging.
Journal
NeuroImage
Author(s)
De Santis L., Spierer L., Clarke S., Murray M.M.
ISSN
1053-8119
Publication state
Published
Issued date
2007
Peer-reviewed
Oui
Volume
37
Number
3
Pages
890-903
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't - Publication Status: ppublish
Abstract
Whether the somatosensory system, like its visual and auditory counterparts, is comprised of parallel functional pathways for processing identity and spatial attributes (so-called what and where pathways, respectively) has hitherto been studied in humans using neuropsychological and hemodynamic methods. Here, electrical neuroimaging of somatosensory evoked potentials (SEPs) identified the spatio-temporal mechanisms subserving vibrotactile processing during two types of blocks of trials. What blocks varied stimuli in their frequency (22.5 Hz vs. 110 Hz) independently of their location (left vs. right hand). Where blocks varied the same stimuli in their location independently of their frequency. In this way, there was a 2x2 within-subjects factorial design, counterbalancing the hand stimulated (left/right) and trial type (what/where). Responses to physically identical somatosensory stimuli differed within 200 ms post-stimulus onset, which is within the same timeframe we previously identified for audition (De Santis, L., Clarke, S., Murray, M.M., 2007. Automatic and intrinsic auditory "what" and "where" processing in humans revealed by electrical neuroimaging. Cereb Cortex 17, 9-17.). Initially (100-147 ms), responses to each hand were stronger to the what than where condition in a statistically indistinguishable network within the hemisphere contralateral to the stimulated hand, arguing against hemispheric specialization as the principal basis for somatosensory what and where pathways. Later (149-189 ms) responses differed topographically, indicative of the engagement of distinct configurations of brain networks. A common topography described responses to the where condition irrespective of the hand stimulated. By contrast, different topographies accounted for the what condition and also as a function of the hand stimulated. Parallel, functionally specialized pathways are observed across sensory systems and may be indicative of a computationally advantageous organization for processing spatial and identity information.
Keywords
Adult, Algorithms, Brain, Brain Mapping, Diagnostic Imaging, Electroencephalography, Evoked Potentials, Somatosensory, Female, Humans, Male, Neural Pathways, Touch
Pubmed
Web of science
Create date
21/01/2008 10:23
Last modification date
20/08/2019 12:24
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