Research Square (Research Square),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Dec. 19, 2023
Abstract
Gonadal
hormone
fluctuations
in
females
have
been
associated
with
symptoms
of
mental
health,
yet
the
underlying
brain
mechanisms
remain
understudied.
Recent
advances
neuroscience
shifted
paradigm
towards
longitudinal
tracking,
enabling
detection
subtle
changes
overlooked
conventional
cross-sectional
analyses.
This
dense-sampling
approach
acknowledges
rhythmic
nature
gonadal
production.
Our
study
employed
three
densely
sampled
who
underwent
imaging
and
venipuncture
(5
to
7
days
per
week)
over
full
menstrual
cycle
investigate
impact
variation
on
structure.
In
two
healthy
typical
cycles,
progesterone
progesterone/estradiol
ratios
were
inversely
spatiotemporal
structural
patterns
across
cycle.
To
probe
neural
effects
hormonal
dysregulation,
we
a
participant
endometriosis,
an
endocrine
disorder
affecting
10%
their
reproductive
years.
Here,
pattern
was
only
estradiol
fluctuations.
findings
suggest
that
hormones
are
short-term
changes,
distinctions
observed
between
endometriosis
cycles.
emphasizes
consideration
individual
dynamics
understanding
plasticity.
Trends in Cognitive Sciences,
Journal Year:
2023,
Volume and Issue:
27(11), P. 1068 - 1084
Published: Sept. 15, 2023
Network
neuroscience
has
emphasized
the
connectional
properties
of
neural
elements
-
cells,
populations,
and
regions.
This
come
at
expense
anatomical
functional
connections
that
link
these
to
one
another.
A
new
perspective
namely
emphasizes
'edges'
may
prove
fruitful
in
addressing
outstanding
questions
network
neuroscience.
We
highlight
recently
proposed
'edge-centric'
method
review
its
current
applications,
merits,
limitations.
also
seek
establish
conceptual
mathematical
links
between
this
previously
approaches
science
neuroimaging
literature.
conclude
by
presenting
several
avenues
for
future
work
extend
refine
existing
edge-centric
analysis.
NeuroImage,
Journal Year:
2022,
Volume and Issue:
260, P. 119476 - 119476
Published: July 14, 2022
Recent
work
identified
single
time
points
("events")
of
high
regional
cofluctuation
in
functional
Magnetic
Resonance
Imaging
(fMRI)
which
contain
more
large-scale
brain
network
information
than
other,
low
points.
This
suggested
that
events
might
be
a
discrete,
temporally
sparse
signal
drives
connectivity
(FC)
over
the
timeseries.
However,
different,
not
yet
explored
possibility
is
differences
between
are
driven
by
sampling
variability
on
constant,
static,
noisy
signal.
Using
combination
real
and
simulated
data,
we
examined
relationship
structure
asked
if
this
was
unique,
or
it
could
arise
from
alone.
First,
show
discrete
-
there
gradually
increasing
cofluctuation;
∼50%
samples
very
strong
structure.
Second,
using
simulations
predicted
static
FC.
Finally,
randomly
selected
can
capture
about
as
well
events,
largely
because
their
temporal
spacing.
Together,
these
results
suggest
that,
while
exhibit
particularly
representations
FC,
little
evidence
unique
timepoints
drive
FC
Instead,
parsimonious
explanation
for
data
but
noisy,
NeuroImage Clinical,
Journal Year:
2022,
Volume and Issue:
35, P. 103055 - 103055
Published: Jan. 1, 2022
Most
neuroimaging
studies
of
post-stroke
recovery
rely
on
analyses
derived
from
standard
node-centric
functional
connectivity
to
map
the
distributed
effects
in
stroke
patients.
Here,
given
importance
nonlocal
and
diffuse
damage,
we
use
an
edge-centric
approach
order
provide
alternative
description
this
disorder.
These
techniques
allow
for
rendering
metrics
such
as
normalized
entropy,
which
describes
diversity
edge
communities
at
each
node.
Moreover,
enables
identification
high
amplitude
co-fluctuations
fMRI
time
series.
We
found
that
entropy
is
associated
with
lesion
severity
continually
increases
across
patients'
recovery.
Furthermore,
not
only
relate
but
are
also
level
The
current
study
first
application
a
clinical
population
longitudinal
dataset
demonstrates
how
different
perspective
data
analysis
can
further
characterize
topographic
modulations
brain
dynamics.
Communications Biology,
Journal Year:
2024,
Volume and Issue:
7(1)
Published: Jan. 24, 2024
Abstract
Previous
studies
have
adopted
an
edge-centric
framework
to
study
fine-scale
network
dynamics
in
human
fMRI.
To
date,
however,
no
applied
this
data
collected
from
model
organisms.
Here,
we
analyze
structural
and
functional
imaging
lightly
anesthetized
mice
through
lens.
We
find
evidence
of
“bursty”
events
-
brief
periods
high-amplitude
connectivity.
Further,
show
that
on
a
per-frame
basis
best
explain
static
FC
can
be
divided
into
series
hierarchically-related
clusters.
The
co-fluctuation
patterns
associated
with
each
cluster
centroid
link
distinct
anatomical
areas
largely
adhere
the
boundaries
algorithmically
detected
brain
systems.
then
investigate
connectivity
undergirding
patterns.
induce
modular
bipartitions
inter-areal
axonal
projections.
Finally,
replicate
these
same
findings
dataset.
In
summary,
report
recapitulates
organism
many
phenomena
observed
previously
analyses
data.
However,
unlike
subjects,
murine
nervous
system
is
amenable
invasive
experimental
perturbations.
Thus,
sets
stage
for
future
investigation
causal
origins
co-fluctuations.
Moreover,
cross-species
consistency
reported
enhances
likelihood
translation.
Scientific Reports,
Journal Year:
2023,
Volume and Issue:
13(1)
Published: Sept. 21, 2023
Abstract
Large-scale
brain
networks
reveal
structural
connections
as
well
functional
synchronization
between
distinct
regions
of
the
brain.
The
latter,
referred
to
connectivity
(FC),
can
be
derived
from
neuroimaging
techniques
such
magnetic
resonance
imaging
(fMRI).
FC
studies
have
shown
that
are
severely
disrupted
by
stroke.
However,
since
data
usually
large
and
high-dimensional,
extracting
clinically
useful
information
this
vast
amount
is
still
a
great
challenge,
our
understanding
consequences
stroke
remains
limited.
Here,
we
propose
dimensionality
reduction
approach
simplify
analysis
complex
neural
data.
By
using
autoencoders,
find
low-dimensional
representation
encoding
fMRI
which
preserves
typical
anomalies
known
present
in
patients.
employing
latent
representations
emerging
enhanced
patients’
diagnostics
severity
classification.
Furthermore,
showed
how
increased
accuracy
recovery
prediction.
Human Brain Mapping,
Journal Year:
2024,
Volume and Issue:
45(10)
Published: July 9, 2024
Abstract
Brain
activity
continuously
fluctuates
over
time,
even
if
the
brain
is
in
controlled
(e.g.,
experimentally
induced)
states.
Recent
years
have
seen
an
increasing
interest
understanding
complexity
of
these
temporal
variations,
for
example
with
respect
to
developmental
changes
function
or
between‐person
differences
healthy
and
clinical
populations.
However,
psychometric
reliability
signal
variability
measures—which
important
precondition
robust
individual
as
well
longitudinal
research—is
not
yet
sufficiently
studied.
We
examined
(split‐half
correlations)
test–retest
correlations
task‐free
(resting‐state)
BOLD
fMRI
split‐half
seven
functional
task
data
sets
from
Human
Connectome
Project
evaluate
their
reliability.
observed
good
excellent
measures
derived
rest
activation
time
series
(standard
deviation,
mean
absolute
successive
difference,
squared
difference),
moderate
same
under
conditions.
estimates
(several
entropy
dimensionality
measures)
showed
reliabilities
both,
calculated
also
time‐resolved
(dynamic)
connectivity
measures,
but
poor
series.
Global
(i.e.,
across
cortical
regions)
tended
show
higher
than
region‐specific
estimates.
Larger
subcortical
regions
similar
regions,
small
lower
reliability,
especially
measures.
Lastly,
we
that
scores
are
only
minorly
dependent
on
scan
length
replicate
our
results
different
parcellation
denoising
strategies.
These
suggest
well‐suited
research.
Temporal
global
provides
novel
approach
robustly
quantifying
dynamics
function.
Practitioner
Points
Variability
Measures
can
quantify
neural
dynamics.
Length
has
a
minor
effect
Human Brain Mapping,
Journal Year:
2024,
Volume and Issue:
45(11)
Published: July 19, 2024
Abstract
Cyclic
fluctuations
in
hypothalamic–pituitary–gonadal
axis
(HPG‐axis)
hormones
exert
powerful
behavioral,
structural,
and
functional
effects
through
actions
on
the
mammalian
central
nervous
system.
Yet,
very
little
is
known
about
how
these
alter
structural
nodes
information
highways
of
human
brain.
In
a
study
30
naturally
cycling
women,
we
employed
multidimensional
diffusion
T
1
‐weighted
imaging
during
three
estimated
menstrual
cycle
phases
(menses,
ovulation,
mid‐luteal)
to
investigate
whether
HPG‐axis
hormone
concentrations
co‐fluctuate
with
alterations
white
matter
(WM)
microstructure,
cortical
thickness
(CT),
brain
volume.
Across
whole
brain,
17β‐estradiol
luteinizing
(LH)
were
directly
proportional
anisotropy
(μFA;
17β‐estradiol:
β
=
0.145,
highest
density
interval
(HDI)
[0.211,
0.4];
LH:
0.111,
HDI
[0.157,
0.364]),
while
follicle‐stimulating
(FSH)
was
CT
(
0
.162,
[0.115,
0.678]).
Within
several
individual
regions,
FSH
progesterone
demonstrated
opposing
relationships
mean
diffusivity
D
iso
)
CT.
These
regions
mainly
reside
within
temporal
occipital
lobes,
implications
for
limbic
visual
systems.
Finally,
associated
increased
tissue
0.66,
[0.607,
15.845])
decreased
cerebrospinal
fluid
(CSF;
−0.749,
[−11.604,
−0.903])
volumes,
total
volume
remaining
unchanged.
results
are
first
report
simultaneous
brain‐wide
changes
WM
microstructure
coinciding
cycle‐driven
rhythms.
Effects
observed
both
classically
receptor‐dense
(medial
lobe,
prefrontal
cortex)
other
located
across
frontal,
occipital,
temporal,
parietal
lobes.
Our
suggest
that
may
have
significant
impacts
entire
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 10, 2025
In
this
paper,
we
investigate
the
edge
controllability
properties
of
macaque
structural
connectome,
which
is
reconstructed
using
optimal
tractography
parameters.
We
derive
expression
modal
and
average
controllability,
providing
a
mathematical
framework
to
analyze
their
roles
from
network
systems
perspective.
Further,
establish
relationship
between
two
measures,
insights
into
functional
implications.
also
identify
top
edges
with
highest
values,
may
be
critical
in
facilitating
state
transitions
within
brain
network.
These
findings
have
implications
for
neurostimulation
interventions.