NeuroImage 50 (2010) 1148–1167 ALE meta-analysis of action observation and imitation in the human...
-
Upload
peter-dawson -
Category
Documents
-
view
214 -
download
0
Transcript of NeuroImage 50 (2010) 1148–1167 ALE meta-analysis of action observation and imitation in the human...
NeuroImage 50 (2010) 1148–1167
ALE meta-analysis of action observation and imitation in the human brain
Svenja Caspers,Karl Zillesa, Angela R.Laird, SimonB.Eickhoff
Background
• Mirror neuron system in the macaque brain (Gallese et al., 1996)
• Evidence for possible “mirror areas” in humans based on functional neuroimaging experiments
• Observation and imitation are closely related
• Are observation and imitation sustained by the same neuronal networks?
AIM
Identification of cortical areas consistently involved in action observation and imitation…
… by a quantitive (coordinate based) meta-analysis of the current neuroimaging literature
Materials & Methods• 139 experiments (fMRI and PET),1289 subjects, 1932 activation foci ( Talairach, MNI coordinates)
• Tasks, effectors and instructions
Material & MethodsActivation likelihood estimation (ALE) algorithm
1 study
1 Map
Foci from all studies
Many foci Each foci = centre of a 3D Gaussian probability distribution
Input Output
Union activation modelled map (MA)
Voxel-wise ALE scores
True convergence?Comparison of “true” scores with scores in null distribution (baseline activation)
Symmetrical activation across both hemispheres
Action Observation Network
Action Observation Network……subanalysis for effectors
No FFA/FBA activation BA45 only in right hemisphere
As hand observation but with lower statistical power
FFA/FBA only in right hemisphere hIP3 only in left hemisphere (the only consistent parietal activation)
As nonHand observation No consistent SMA activation
Contrast analysis between hand action observation and observation of non-hand actions
A: hand observationC : non-hand observation
Action Observation Network……subanalysis for instructions
Comparable network to main analysis
No parietal activation Consistent activation of dPMC-BA6, pMTG and extrastriate areas
Contrast analysis between the two instructions
No stronger activation for the instruction “observe to imitate” in any region BUT only 8 experiments were used
A: passively observeB : observe to imitate
Action Observation Network……subanalysis for object-related hand actions
Bilaterally: BA 44, BA6, IPL-PFt, SPL (7a), pMTG,V5 Right hemisphere: S1, IPS-hIP3
Activation of temporo-occipital areas
Contrast analysis between object-related hand actions and non-object-related hand action
A: object-related hand actionB : non-object-related hand action
Action Imitation Network
Bilaterally: BA 44, BA 6, SMA, SFG, S1 (area 2), IPL-PFt, V5 Left hemisphere: pMTG Right hemisphere: IPL-PFcm, FFA/FBA, frontal aspect of insular cortex
Action Imitation Network……subanalysis for effectors
Comparable to the main analysis
Comparable to the main analysis pMTG bilaterally activated
Activation of BA 4, BA 6, BA 44 SFG No temporo-occipital activation
Conjunction analyses
Bilaterally: BA 44, BA 6, SMA, PFt, PFop, S1 (area 2), V5 Left hemisphere: pMTG Right hemisphere: FFA/FBA
Contrast analyses
Observation Imitation
Rostro-dorsal part of BA 44 (area BA45- bilaterally)
Caudo-ventral part of BA 44 (bilaterally)
BA 6, pMTG, V5 (bilaterally)
IPL-PFt/Pfop (left hemisphere)
SPL (right hemisphere) S1 (area 2),IPL-PFt, FFA/FBA (right hemisphere)
DiscussionMethodological considerations
• Coordinate based meta-analysis vs. image based meta-analysis
• Potential presence of confounding factors
• No information for the strength of resulting activation
• Account for sample size
DiscussionAreas involved in each network
• Expanded Mirror Neuron System• In humans, observation and imitation networks are similar, if not the same (differences in macaque brain)• BA 44 and PFt/hIP3 homolog to F5 and PFG/PF of macaque respectively • BA 44 => initiation and termination of simple actions (imitation) BA 45 =>supraordinate aspect of action• SMA mainly activated in non-hand tasks• pMTG involved in the processing of biological motion• V5 involved in motion perception • FFA/FBA serves as an encoder of facial and body stimuli• S1-top down modulation from associative areas
DiscussionNeural correlates of action observation
• Transient inactivation of observation network- related areas result in impairment of action observation ability• Somatotopy of the involved parts of observation network?• Activation’s independency from the effectors• Possible functions of the network: - Feedback control of an action (SPL, IPS, BA 6)-optic ataxia - Implicit processing of object features and their integration within the observed motor act (fronto-parietal areas) - Composition of the appropriate motor program (dPMC)
Neural correlates of action imitation
• Bilateral pattern of activation
Thank
you!