Understanding actions of others: the electrodynamics of the left and right hemispheres. A high-density EEG neuroimaging study.

BACKGROUND: When we observe an individual performing a motor act (e.g. grasping a cup) we get two types of information on the basis of how the motor act is done and the context: what the agent is doing (i.e. grasping) and the intention underlying it (i.e. grasping for drinking). Here we examined the...

Full description

Bibliographic Details
Main Authors: Stephanie Ortigue, Corrado Sinigaglia, Giacomo Rizzolatti, Scott T Grafton
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2010-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC2921336?pdf=render
_version_ 1818506872775245824
author Stephanie Ortigue
Corrado Sinigaglia
Giacomo Rizzolatti
Scott T Grafton
author_facet Stephanie Ortigue
Corrado Sinigaglia
Giacomo Rizzolatti
Scott T Grafton
author_sort Stephanie Ortigue
collection DOAJ
description BACKGROUND: When we observe an individual performing a motor act (e.g. grasping a cup) we get two types of information on the basis of how the motor act is done and the context: what the agent is doing (i.e. grasping) and the intention underlying it (i.e. grasping for drinking). Here we examined the temporal dynamics of the brain activations that follow the observation of a motor act and underlie the observer's capacity to understand what the agent is doing and why. METHODOLOGY/PRINCIPAL FINDINGS: Volunteers were presented with two-frame video-clips. The first frame (T0) showed an object with or without context; the second frame (T1) showed a hand interacting with the object. The volunteers were instructed to understand the intention of the observed actions while their brain activity was recorded with a high-density 128-channel EEG system. Visual event-related potentials (VEPs) were recorded time-locked with the frame showing the hand-object interaction (T1). The data were analyzed by using electrical neuroimaging, which combines a cluster analysis performed on the group-averaged VEPs with the localization of the cortical sources that give rise to different spatio-temporal states of the global electrical field. Electrical neuroimaging results revealed four major steps: 1) bilateral posterior cortical activations; 2) a strong activation of the left posterior temporal and inferior parietal cortices with almost a complete disappearance of activations in the right hemisphere; 3) a significant increase of the activations of the right temporo-parietal region with simultaneously co-active left hemispheric sources, and 4) a significant global decrease of cortical activity accompanied by the appearance of activation of the orbito-frontal cortex. CONCLUSIONS/SIGNIFICANCE: We conclude that the early striking left hemisphere involvement is due to the activation of a lateralized action-observation/action execution network. The activation of this lateralized network mediates the understanding of the goal of object-directed motor acts (mirror mechanism). The successive right hemisphere activation indicates that this hemisphere plays an important role in understanding the intention of others.
first_indexed 2024-12-10T22:10:35Z
format Article
id doaj.art-3cb9bb2b9e4f41838ab793e831349b9b
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-10T22:10:35Z
publishDate 2010-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-3cb9bb2b9e4f41838ab793e831349b9b2022-12-22T01:31:37ZengPublic Library of Science (PLoS)PLoS ONE1932-62032010-01-0158e1216010.1371/journal.pone.0012160Understanding actions of others: the electrodynamics of the left and right hemispheres. A high-density EEG neuroimaging study.Stephanie OrtigueCorrado SinigagliaGiacomo RizzolattiScott T GraftonBACKGROUND: When we observe an individual performing a motor act (e.g. grasping a cup) we get two types of information on the basis of how the motor act is done and the context: what the agent is doing (i.e. grasping) and the intention underlying it (i.e. grasping for drinking). Here we examined the temporal dynamics of the brain activations that follow the observation of a motor act and underlie the observer's capacity to understand what the agent is doing and why. METHODOLOGY/PRINCIPAL FINDINGS: Volunteers were presented with two-frame video-clips. The first frame (T0) showed an object with or without context; the second frame (T1) showed a hand interacting with the object. The volunteers were instructed to understand the intention of the observed actions while their brain activity was recorded with a high-density 128-channel EEG system. Visual event-related potentials (VEPs) were recorded time-locked with the frame showing the hand-object interaction (T1). The data were analyzed by using electrical neuroimaging, which combines a cluster analysis performed on the group-averaged VEPs with the localization of the cortical sources that give rise to different spatio-temporal states of the global electrical field. Electrical neuroimaging results revealed four major steps: 1) bilateral posterior cortical activations; 2) a strong activation of the left posterior temporal and inferior parietal cortices with almost a complete disappearance of activations in the right hemisphere; 3) a significant increase of the activations of the right temporo-parietal region with simultaneously co-active left hemispheric sources, and 4) a significant global decrease of cortical activity accompanied by the appearance of activation of the orbito-frontal cortex. CONCLUSIONS/SIGNIFICANCE: We conclude that the early striking left hemisphere involvement is due to the activation of a lateralized action-observation/action execution network. The activation of this lateralized network mediates the understanding of the goal of object-directed motor acts (mirror mechanism). The successive right hemisphere activation indicates that this hemisphere plays an important role in understanding the intention of others.http://europepmc.org/articles/PMC2921336?pdf=render
spellingShingle Stephanie Ortigue
Corrado Sinigaglia
Giacomo Rizzolatti
Scott T Grafton
Understanding actions of others: the electrodynamics of the left and right hemispheres. A high-density EEG neuroimaging study.
PLoS ONE
title Understanding actions of others: the electrodynamics of the left and right hemispheres. A high-density EEG neuroimaging study.
title_full Understanding actions of others: the electrodynamics of the left and right hemispheres. A high-density EEG neuroimaging study.
title_fullStr Understanding actions of others: the electrodynamics of the left and right hemispheres. A high-density EEG neuroimaging study.
title_full_unstemmed Understanding actions of others: the electrodynamics of the left and right hemispheres. A high-density EEG neuroimaging study.
title_short Understanding actions of others: the electrodynamics of the left and right hemispheres. A high-density EEG neuroimaging study.
title_sort understanding actions of others the electrodynamics of the left and right hemispheres a high density eeg neuroimaging study
url http://europepmc.org/articles/PMC2921336?pdf=render
work_keys_str_mv AT stephanieortigue understandingactionsofotherstheelectrodynamicsoftheleftandrighthemispheresahighdensityeegneuroimagingstudy
AT corradosinigaglia understandingactionsofotherstheelectrodynamicsoftheleftandrighthemispheresahighdensityeegneuroimagingstudy
AT giacomorizzolatti understandingactionsofotherstheelectrodynamicsoftheleftandrighthemispheresahighdensityeegneuroimagingstudy
AT scotttgrafton understandingactionsofotherstheelectrodynamicsoftheleftandrighthemispheresahighdensityeegneuroimagingstudy