Functional Connectivity: Mechanisms & Applications
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Wednesday May 11th
Room 510 |
16:00 - 18:00 |
Moderators: |
Catherine Chang and Richard Wise |
16:00 |
428. |
White matter cerebral
blood flow is inversely correlated with structural and
functional connectivity in the human brain ![](play.gif)
Sina Aslan1,2, Hao Huang1,2,
Jinsoo Uh1, Virendra Mishra1,2,
Guanghua Xiao3, Matthias van Osch4,
and Hanzhang Lu1,2
1Advanced Imaging Research Center, University
of Texas at Southwestern Medical Center, Dallas, TX,
United States, 2Biomedical
Engineering Graduate Program, University of Texas at
Southwestern Medical Center, Dallas, TX, United States, 3Division
of Biostatistics, Department of Clinical Sciences,
University of Texas at Southwestern Medical Center,
Dallas, TX, United States, 4Department
of Radiology, Leiden University Medical Center, Leiden,
Netherlands
Some evidence has suggested that gray matter functional
connectivity is supported by structural connections via
white matter fiber tracts. We therefore further
hypothesized that functional measures of the white
matter, e.g. perfusion, may have a more direct link to
gray matter connectivity. Here we used ASL and DTI to
measure fiber tract-specific CBF and compared it to
fcMRI connectivity in the terminal gray matter. Across
fiber tracts, CBF showed a paradoxically inverse
correlation with FA. An inverse correlation was also
observed between tract-specific CBF and the functional
connectivity in the gray matters connected by the tract.
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16:12 |
429. |
Forty Weeks of Rest: An
Investigation into Functional Network Stability ![](play.gif)
Suresh Emmanuel Joel1,2, Craig K Jones1,2,
Brian S Caffo3, Peter C M van Zijl1,2,
and James J Pekar1,2
1Radiology, Johns Hopkins University,
Baltimore, MD, United States, 2FM
Kirby Research Center for Functional Brain Imaging,
Kennedy Krieger Institute, Baltimore, MD, United States, 3Biostatistics,
Johns Hopkins University, Baltimore, MD, United States
Resting state functional connectivity data were acquired
in one participant over forty weekly sessions, to
estimate intra-subject variability of functional
networks. Spatial independent component analysis using
temporal concatenation yielded fourteen functional
networks. Using between-network connectivity, networks
were classified into three classes: exteroceptive
(attention, somatosensory, motor, visual, and auditory),
default (default mode network and fronto-parietal), and
dorsal streams (right and left dorsal stream). Default
networks were more stable than exteroceptive networks,
and were more connected to one another than to
exteroceptive networks; the more variable exteroceptive
networks were more connected to one another than to
default networks.
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16:24 |
430. |
Symmetry of Resting-State
Functional Connectivity in FMRI: High Correlation Across
Hemispheres Exists with or without Callosal Connection ![](play.gif)
Hang Joon Jo1, Ziad S Saad1, Steve
J Gotts2, Richard C Reynolds1,
Patricia Christidis1, Daniel R Glen1,
Alex Martin2, and Robert W Cox1
1Statistical and Scientific Computing Core,
National Institute of Mental Health, National Institutes
of Health, Bethesda, MD, United States, 2Cognitive
Neuropsychology Section, Laboratory of Brain and
Cognition, National Institute of Mental Health, National
Institutes of Health, Bethesda, MD, United States
We evaluate the fine organization of cross-hemispheric
correlations maps in a variety of brain regions outside
somatotopic cortex, including occipital, temporal, and
prefrontal areas. We find that the fine-grained nature
of the symmetric correlation maps carries over more
generally to these other areas of cortex. However, we
also find that this property carries over equally well
to parts of primary visual cortex that have no direct
callosal connections, namely the cortex along the depth
of the calcarine sulcus that represents the horizontal
meridian in V1. Our results highlight the importance of
considering alternative mechanisms even in circumstances
in which callosal connections are indeed plausible.
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16:36 |
431. |
BOLD Resting State
Networks in Adults with Complete Callosal Agenesis ![](play.gif)
Julian Michael Tyszka1, Lynn K Paul2,
and Ralph Adolphs1,2
1Biology, California Institute of Technology,
Pasadena, CA, United States, 2Humanities
and Social Sciences, California Institute of Technology,
Pasadena, CA, United States
The impact of agenesis of the corpus callosum on resting
state connectivity in the human brain is largely
unknown. In this study, we apply well-established
probabilistic independent component analysis (PICA)
methods to BOLD fMRI time course data in a minimum
deformation space to identify spatial independent
components unique to and absent in callosal agenesis.
Over 80% of neurotypical BOLD resting state networks
identified by group PICA are preserved in adult AgCC
subjects suggesting that compensatory networks
established during brain development play a major role
in this condition.
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16:48 |
432. |
Investigating the
Dependence of Spontaneous Fluctuations in Visual Cortex on
Callosal Connectivity ![](play.gif)
Li-Wei Kuo1, Zhongming Liu1, Jacco
A. de Zwart1, Peter van Gelderen1,
and Jeff H. Duyn1
1Advanced MRI section, LFMI, NINDS, National
Institutes of Health, Bethesda, MD, United States
In this study, we investigated the dependence of
spontaneous fMRI activity in human visual cortex on
callosal connectivity. Interhemispheric correlations in
fMRI studies of spontaneous activity have been partly
attributed to cortico-cortical connections through the
corpus callosum, suggesting these correlations may be
reduced in the part of visual area V1 that lacks these
connections. Using 7T fMRI, regions of interest with
high and low/absent callosal V1 connectivity were
identified with retinotopic mapping, after which
interhemispheric correlations were calculated during
rest. Our preliminary results show that interhemispheric
functional connectivity is organized retinotopically,
with a minimal dependence on mono-synaptic callosal
connectivity. This suggests that interhemispheric
functional connectivity partly arises from
multi-synaptic pathways.
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17:00 |
433. |
Caffeine causes widespread
decreases in resting-state BOLD connectivity and energy ![](play.gif)
Chi Wah Wong1, Valur Olafsson1,
Omer Tal1, and Thomas T Liu1
1Center for Functional MRI, University of
California San Diego, La Jolla, CA, United States
Previous studies have shown that caffeine reduces
resting state BOLD connectivity in the motor cortex,
regions in the default mode network, and the thalamus.
In this study, we show that the caffeine-induced
reductions in BOLD connectivity and energy are
widespread, spanning multiple brain regions.
Specifically, the mean network degree, which is a
measure of the average number of links between brain
regions, is significantly reduced by caffeine.
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17:12 |
434. |
Differential effects of
opioid analgesics on functional connectivity of
cortical-subcortical networks in humans ![](play.gif)
Richard G Wise1, Anna Jolly2,
Kevin Murphy1, C John Evans1, and
Judith E Hall2
1CUBRIC, School of Psychology, Cardiff
University, Cardiff, S. Glamorgan, United Kingdom, 2Department
of Anaesthetics and Intensive Care Medicine, School of
Medicine, Cardiff University, Cardiff, S. Glamorgan,
United Kingdom
Opioids decrease pain-related signals in line with their
analgesic effects but also modify cerebral blood flow in
a pattern consistent with their receptor distribution.
We examined the effect of acute mu-opioid agonist
(remifentanil) administration on functional connectivity
in BOLD FMRI signals. Functional connectivity (temporal
covariation of BOLD signal) was increased between
brainstem and anterior cingulate/insular cortex
consistent with an influence of higher cortical centres
on the pain-control regions of the brainstem. Conversely
functional connectivity between basal ganglia (putamen)
and sensorimotor cortex was reduced, a potential
reflection of the drug’s sedative effects.
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17:24 |
435. |
Prediction of Age Using
Resting-State Functional and Effective Connectivity ![](play.gif)
Zhihao Li1, John A Sexton1,
Gopikrishna Deshpande2, and Xiaoping Hu1
1Biomedical Engineering, Emory University &
Georgia Institute of Technology, Atlanta, GA, United
States, 2Electrical
and Computer Engineering, Auburn University, Auburn, AL,
United States
Using resting-state fMRI, support-vector-machine based
multivariate pattern analysis recently shows capability
of accurate predictions about brain maturity. However,
with more information about inter-regional causal
influences, effective connectivity may possess more
power in characterizing the development of neural
networks. The present study compared age prediction of
these two approaches and showed a relatively better
performance with effective connectivity.
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17:36 |
436. |
Left lateralization of
motor circuit connectivity is associated with better motor
performance in children ![](play.gif)
Anita Dyan Barber1,2, Suresh E Joel1,
Priti Srinivasan2, Simona Spinelli2,
Jim J Pekar1,2, and Stewart H Mostofsky1,2
1Johns Hopkins School of Medicine, Baltimore,
MD, United States, 2Kennedy
Krieger Institute, Baltimore, MD, United States
The association between resting state functional
connectivity within the motor network (Mostofsky et al.,
2009) and motor abilities was examined. Motor
performance was assessed using the PANESS (Denckla,
1985), a standardized battery sensitive to developmental
changes in motor abilities. 40 typically-developing,
right-handed children (ages 8-12) performed the PANESS
outside of the scanner and then were scanned during a 5
minute rest session. Greater mean connectivity within
the left than right hemisphere motor circuit was
significantly correlated with better motor performance.
The results suggest that greater left hemisphere
dominance in motor circuit connectivity is associated
with better motor performance in children.
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17:48 |
437. |
Functional connectivity
MRI reveals memory networks after maze learning in rodents ![](play.gif)
Fatima Ali Nasrallah1, Chen Yow Der-Yow2,
Aryeh Routtenberg3, and Kai-Hsiang Chuang4
1Lab of Molecular Imaging, A*Star Biomedical
Research Institutes, Buona Vista, Singapore, Singapore, 2NIH,
NINDS, 3Northwestern
University, 4A*Star
Biomedical Research Institutes
Functional connectivity MRI has emerged as a means to
map intrinsic brain networks without the need of
explicit tasks. We investigated mapping plasticity of
the rodent brain after a memory task using Morris water
maze. Extensive and enhanced connectivity was seen in
trained rats compared to swim controls, and was
maintained even seven days after training. This is the
first demonstration of brain plasticity following a
cognitive task can be detected in the anesthetized rat
using functional connectivity MRI.
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