Outline
Occipitotemporal Activation Evoked by the
Perception of Human Bodies is Inhibited by the
Presence of the Face
James P. Morris, Kevin A. Pelphrey, & Gregory McCarthy
Brain Imaging and Analysis Center,
Duke University
¾Part 1: Domain Specificity in the
Occipitotemporal Cortex
¾Part 2: The Social Brain in Action
¾Part 3: Perceiving Others With and
Without Visible Faces and Bodies
Face Processing
LOTC
Part 1: Domain Specificity in the
Occipitotemporal Cortex
VOTC
Faces
Letterstrings
Puce et al. (1996); Journal of Neuroscience
Superior Temporal Sulcus
Extrastriate Body Area
R
EBA
Puce et al. (1998); Journal of Neuroscience
MT/V5
Adapted from Downing et al. (2001); Science
1
Part 2: The Social Brain in Action
Social
FFG
Non-Social
FFG
Social
% Change in BOLD Signal
Intensity %
0.60%
Non-Social
Social
0.50%
0.40%
0.30%
0.20%
0.10%
0.00%
-3
1.5
6
10.5
15
19.5
Was the response in FFG and EBA related
to the number of visible body parts?
-0.10%
Time (in seconds)
Non-Social
MOG
EBA
% Change in BOLD Signal
Intensity %
0.85%
0.75%
0.65%
0.55%
0.45%
0.35%
0.25%
0.15%
0.05%
-0.05%
Morris et al. (2005); JOCN
Non-Social
Social
-3
1.5
6
10.5
15
19.5
-0.15%
Time (in seconds)
Part 3: Perceiving Others With and Without
Visible Faces and Bodies
Background
No Occlusion
Face Occlusion
Body Occlusion
2
Active Voxels
Methods
¾ Subjects
¾ 12 healthy young adults
¾ Imaging
¾ 4 Tesla – Inverse Spiral
¾ 1.5 TR
¾ Whole Brain Acquisition
R
¾ Analysis
¾ False Discovery Rate thresholding employed to identify active
voxels
¾ Internal Localizer Approach
¾ Half of all trials used to identify clusters of voxels (functional
ROIs) showing differences between conditions.
¾ Half of all trials used to test for significant differences in peak
hemodynamic response for each ROI.
FDRp < .01
Right EBA
% Signal Change
0.30%
0.20%
0.10%
0.30%
0.20%
0.10%
R
0.00%
0.00%
-3
-0.10%
-0.10%
-3
0
3
6
9
-3
12
0
3
Time (s)
66
99
12
12
0
3
6
9
12
Time (s)
Time (s)
Face Occlusion
Ventral Occipitotemporal Cortex
% Change in BOLD Signal
Body Occlusion
No Occlusion
Body Occlusion
Face Occlusion
No Occlusion
M-VOTC
0.60%
0.40%
LOTC
0.40%
0.30%
0.20%
0.10%
0.20%
0.00%
-0.10%
0.00%
-3
0
3
6
9
12
-0.20%
-3
0
3
6
9
Summary
12
Time (s)
% Change in BOLD Signal
% Signal Change
Left EBA
0.40%
0.40%
% Signal Change
R-STS
0.25%
0.20%
0.15%
0.10%
0.05%
0.00%
-0.05%
-0.10%
0.60%
¾Similar activity in EBA and M-VOTC
L-VOTC
0.40%
¾Strongest response when face is not
visible
VOTC
0.20%
¾Activity evoked by bodies is reduced
when face is visible
0.00%
-0.20%
-3
0
3
6
9
12
Time (s)
R
0.60%
0.40%
0.20%
0.00%
-0.20%
-3
Body Occlusion
Face Occlusion
0
3
6
9
12
No Occlusion
3
0.25%
0.20%
LOTC
Interpretations
0.15%
0.10%
0.05%
0.00%
-0.05%
-0.10%
-3
0
3
6
9
12
Summary
¾Face processing in VOTC and LOTC
¾In STS the presence of a face with or
without a visible body evokes a larger
response than bodies without visible faces
VOTC
¾In L-VOTC the presence of a face with a
visible body evokes the largest response
0.60%
0.40%
¾ The presence of the face modulated activity in the
occipitotemporal cortex
¾ Processing the face reduces the resources available for
processing the body
¾ Processing the face inhibits processing of other stimuli
¾ Why are there limited resources for domain specific
processes?
¾ We hypothesize that initial processing of domain specific
stimuli proceeds in parallel.
¾ Higher order processing of the scene requires selection
among stimuli relevant to the subject’s dispositions and
goals.
0.20%
0.00%
-0.20%
-3
0
3
6
9
12
Acknowledgements
Mary Beth Nebel
Charles Michelich
Michele Diaz
Chris Petty
Brian Marion
Research supported by a Ruth L. Kirchstein National Research Service Award from the
NIMH, grant F32-MH073367 (PI: J.P. Morris); NIMH grant MH-05286 (PI: G. McCarthy);
The Department of Veterans Affairs; and a Young Investigator Award from Cure Autism
Now (PI: J.P. Morris). This presentation is available at http://www.biac.duke.edu
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