NeuroImage Clinical,
Journal Year:
2020,
Volume and Issue:
26, P. 102163 - 102163
Published: Jan. 1, 2020
Major
depressive
disorder
(MDD)
is
known
to
be
characterized
by
altered
brain
functional
connectivity
(FC)
patterns.
However,
whether
and
how
the
features
of
dynamic
FC
would
change
in
patients
with
MDD
are
unclear.
In
this
study,
we
aimed
characterize
using
a
large
multi-site
sample
novel
network-based
approach.
Resting-state
magnetic
resonance
imaging
(fMRI)
data
were
acquired
from
total
460
473
healthy
controls,
as
part
REST-meta-MDD
consortium.
networks
constructed
for
each
subject
sliding-window
Multiple
spatio-temporal
networks,
including
temporal
variability,
clustering
efficiency,
then
compared
between
subjects
at
both
global
local
levels.
The
group
showed
significantly
higher
lower
correlation
coefficient
(indicating
decreased
clustering)
shorter
characteristic
path
length
increased
efficiency)
controls
(corrected
p
<
3.14×10−3).
Corresponding
changes
mainly
found
default-mode,
sensorimotor
subcortical
areas.
Measures
variability
correlated
depression
severity
0.05).
Moreover,
observed
between-group
differences
robustly
present
first-episode,
drug-naïve
(FEDN)
non-FEDN
patients.
Our
findings
suggest
that
excessive
variations
FC,
reflecting
abnormal
communications
large-scale
bran
over
time,
may
underlie
neuropathology
MDD.
NeuroImage,
Journal Year:
2019,
Volume and Issue:
203, P. 116157 - 116157
Published: Sept. 5, 2019
Once
considered
mere
noise,
fMRI-based
functional
connectivity
has
become
a
major
neuroscience
tool
in
part
due
to
early
studies
demonstrating
its
reliability.
These
fundamental
revealed
only
the
tip
of
iceberg;
over
past
decade,
many
test-retest
reliability
have
continued
add
nuance
our
understanding
this
complex
topic.
A
summary
these
diverse
and
at
times
contradictory
perspectives
is
needed.
We
aimed
summarize
existing
knowledge
regarding
most
basic
unit
analysis:
individual
edge
level.
This
entailed
(1)
meta-analytic
estimate
(2)
review
factors
influencing
search
Scopus
was
conducted
identify
that
estimated
edge-level
To
facilitate
comparisons
across
studies,
eligibility
restricted
measuring
via
intraclass
correlation
coefficient
(ICC).
The
meta-analysis
included
random
effects
pooled
mean
ICC,
with
nested
within
datasets.
narrative
ICC.
From
an
initial
pool
212
44
were
identified
for
qualitative
25
quantitative
meta-analysis.
On
average,
edges
exhibited
"poor"
ICC
0.29
(95%
CI
=
0.23
0.36).
reliable
measurements
tended
involve:
stronger,
within-network,
cortical
edges,
eyes
open,
awake,
active
recordings,
(3)
more
within-subject
data,
(4)
shorter
intervals,
(5)
no
artifact
correction
(likely
artifact),
(6)
full
correlation-based
shrinkage.
study
represents
first
systematic
investigating
connectivity.
Key
findings
suggest
there
room
improvement,
but
care
should
be
taken
avoid
promoting
expense
validity.
By
pooling
key
facet
accuracy,
supports
broader
efforts
improve
inferences
field.
American Journal of Psychiatry,
Journal Year:
2019,
Volume and Issue:
176(7), P. 512 - 520
Published: Jan. 30, 2019
The
interpretability
of
results
in
psychiatric
neuroimaging
is
significantly
limited
by
an
overreliance
on
correlational
relationships.
Purely
studies
cannot
alone
determine
whether
behavior-imaging
relationships
are
causal
to
illness,
functionally
compensatory
processes,
or
purely
epiphenomena.
Negative
symptoms
(e.g.,
anhedonia,
amotivation,
and
expressive
deficits)
refractory
current
medications
among
the
foremost
causes
disability
schizophrenia.
authors
used
a
two-step
approach
identifying
then
empirically
testing
brain
network
model
schizophrenia
symptoms.In
first
cohort
(N=44),
data-driven
resting-state
functional
connectivity
analysis
was
identify
with
that
corresponds
negative
symptom
severity.
In
second
(N=11),
this
modulated
5
days
twice-daily
transcranial
magnetic
stimulation
(TMS)
cerebellar
midline.A
breakdown
specific
dorsolateral
prefrontal
cortex-to-cerebellum
directly
corresponded
Restoration
TMS
amelioration
symptoms,
showing
statistically
significant
strong
relationship
change
response
change.These
demonstrate
between
cerebellum
right
cortex
associated
severity
correction
ameliorates
severity,
supporting
novel
hypothesis
for
medication-refractory
suggesting
manipulation
may
establish
markers
clinical
phenomena.
Frontiers in Neuroscience,
Journal Year:
2016,
Volume and Issue:
10
Published: Nov. 10, 2016
Functional
Magnetic
Resonance
Imaging
(fMRI)
studies
have
become
increasingly
popular
both
with
clinicians
and
researchers
as
they
are
capable
of
providing
unique
insights
into
brain
functions.
However,
multiple
technical
considerations
(ranging
from
specifics
paradigm
design
to
imaging
artifacts,
complex
protocol
definition,
multitude
processing
methods
analysis,
well
intrinsic
methodological
limitations)
must
be
considered
addressed
in
order
optimize
fMRI
analysis
arrive
at
the
most
accurate
grounded
interpretation
data.
In
practice,
researcher/clinician
choose,
many
available
options,
suitable
software
tool
for
each
stage
pipeline.
Herein
we
provide
a
straightforward
guide
designed
address,
major
stages,
techniques,
tools
involved
process.
We
developed
this
help
those
new
technique
overcome
critical
difficulties
its
use,
serve
resource
neuroimaging
community.
Psychological Medicine,
Journal Year:
2018,
Volume and Issue:
49(5), P. 852 - 860
Published: June 18, 2018
Abstract
Background
Major
depressive
disorder
(MDD)
is
associated
with
high
risk
of
suicide.
Conventional
neuroimaging
works
showed
abnormalities
static
brain
activity
and
connectivity
in
MDD
suicidal
ideation
(SI).
However,
little
known
regarding
alterations
dynamics.
More
broadly,
it
remains
unclear
whether
temporal
dynamics
the
could
predict
prognosis
SI.
Methods
We
included
patients
(
n
=
48)
without
SI
age-,
gender-,
education-matched
healthy
controls
30)
who
underwent
resting-state
functional
magnetic
resonance
imaging.
first
assessed
dynamic
amplitude
low-frequency
fluctuation
(dALFF)
–
a
proxy
for
intrinsic
(iBA)
using
sliding-window
analysis.
Furthermore,
variability
(dynamics)
iBA
was
quantified
as
variance
dALFF
over
time.
In
addition,
prediction
severity
from
conducted
general
linear
model.
Results
Compared
SI,
group
decreased
(less
variability)
dorsal
anterior
cingulate
cortex,
left
orbital
frontal
inferior
gyrus,
hippocampus.
Importantly,
these
variabilities
be
used
to
r
0.43,
p
0.03),
whereas
ALFF
not
current
data
set.
Conclusions
These
findings
suggest
that
regions
involved
executive
emotional
processing
are
patients.
This
novel
predictive
model
useful
developing
neuromarkers
clinical
applications.
Schizophrenia Bulletin,
Journal Year:
2024,
Volume and Issue:
50(6), P. 1326 - 1336
Published: Feb. 24, 2024
Abstract
Background
and
Hypothesis
Neuroimaging
studies
investigating
the
neural
substrates
of
auditory
verbal
hallucinations
(AVH)
in
schizophrenia
have
yielded
mixed
results,
which
may
be
reconciled
by
network
localization.
We
sought
to
examine
whether
AVH-state
AVH-trait
brain
alterations
localize
common
or
distinct
networks.
Study
Design
initially
identified
reported
48
previous
studies.
By
integrating
these
affected
locations
with
large-scale
discovery
validation
resting-state
functional
magnetic
resonance
imaging
datasets,
we
then
leveraged
novel
connectivity
mapping
construct
dysfunctional
Results
The
neuroanatomically
heterogeneous
localized
specific
comprised
a
broadly
distributed
set
regions
mainly
involving
auditory,
salience,
basal
ganglia,
language,
sensorimotor
Contrastingly,
manifested
as
pattern
circumscribed
principally
implicating
caudate
inferior
frontal
gyrus.
Additionally,
aligned
neuromodulation
targets
for
effective
treatment
AVH,
indicating
possible
clinical
relevance.
Conclusions
Apart
from
unifying
seemingly
irreproducible
neuroimaging
results
across
prior
AVH
studies,
our
findings
suggest
different
mechanisms
underlying
state
trait
perspective
more
inform
future
AVH.