bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Oct. 25, 2023
Our
brains
are
in
a
near
constant
state
of
generating
predictions,
extracting
regularities
from
seemingly
random
sensory
inputs
to
support
later
cognition
and
behavior,
process
called
statistical
learning
(SL).
Yet,
the
activity
patterns
across
cortex
subcortex
that
this
form
associative
remain
unresolved.
Here
we
use
human
fMRI
visual
SL
task
investigate
changes
neural
as
participants
implicitly
learn
associations
sequence.
By
projecting
functional
connectivity
onto
low-dimensional
manifold,
reveal
is
selectively
supported
by
along
single
dimension
spanning
visual-parietal
perirhinal
(PRC).
During
learning,
expanded
dimension,
segregating
other
networks,
while
dorsal
attention
network
(DAN)
regions
contracted,
integrating
with
higher-order
transmodal
cortex.
When
violated
learned
associations,
PRC
entorhinal
cortex,
which
initially
showed
no
evidence
learning-related
effects,
now
contracted
default
mode
DAN,
decreasing
covariance
Whereas
previous
studies
have
linked
either
broad
cortical
or
medial
temporal
lobe
changes,
our
findings
suggest
an
integrative
view,
whereby
reorganize
during
association
formation,
respond
their
violation.
Cognition
and
attention
arise
from
the
adaptive
coordination
of
neural
systems
in
response
to
external
internal
demands.
The
low-dimensional
latent
subspace
that
underlies
large-scale
dynamics
relationships
these
cognitive
attentional
states,
however,
are
unknown.
We
conducted
functional
magnetic
resonance
imaging
as
human
participants
performed
tasks,
watched
comedy
sitcom
episodes
an
educational
documentary,
rested.
Whole-brain
traversed
a
common
set
states
spanned
canonical
gradients
brain
organization,
with
global
desynchronization
among
networks
modulating
state
transitions.
Neural
were
synchronized
across
people
during
engaging
movie
watching
aligned
narrative
event
structures.
reflected
fluctuations
such
different
indicated
engaged
task
naturalistic
contexts,
whereas
lapses
both
contexts.
Together,
results
demonstrate
traversals
along
organization
reflect
dynamics.
Nature Communications,
Journal Year:
2023,
Volume and Issue:
14(1)
Published: June 9, 2023
Hemispheric
specialization
is
a
fundamental
feature
of
human
brain
organization.
However,
it
not
yet
clear
to
what
extent
the
lateralization
specific
cognitive
processes
may
be
evident
throughout
broad
functional
architecture
cortex.
While
majority
people
exhibit
left-hemispheric
language
dominance,
substantial
minority
population
shows
reverse
lateralization.
Using
twin
and
family
data
from
Human
Connectome
Project,
we
provide
evidence
that
atypical
dominance
associated
with
global
shifts
in
cortical
Individuals
organization
corresponding
hemispheric
differences
macroscale
gradients
situate
discrete
large-scale
networks
along
continuous
spectrum,
extending
unimodal
through
association
territories.
Analyses
reveal
both
gradient
asymmetries
are,
part,
driven
by
genetic
factors.
These
findings
pave
way
for
deeper
understanding
origins
relationships
linking
population-level
variability
properties
NeuroImage,
Journal Year:
2023,
Volume and Issue:
272, P. 120059 - 120059
Published: March 30, 2023
Low-dimensional
representations
are
increasingly
used
to
study
meaningful
organizational
principles
within
the
human
brain.
Most
notably,
sensorimotor-association
axis
consistently
explains
most
variance
in
connectome
as
its
so-called
principal
gradient,
suggesting
that
it
represents
a
fundamental
principle.
While
recent
work
indicates
these
low
dimensional
relatively
robust,
they
limited
by
modeling
only
certain
aspects
of
functional
connectivity
structure.
To
date,
majority
studies
have
restricted
approaches
strongest
connections
brain,
treating
weaker
or
negative
noise
despite
evidence
structure
among
them.
The
present
examines
gradients
across
full
range
strengths
and
explores
implications
for
outcomes
individual
differences,
identifying
potential
dependencies
on
thresholds
opportunities
improve
prediction
tasks.
Interestingly,
emerged
gradient
entire
levels.
Moreover,
at
intermediate
encoded
better
followed
individual-specific
anatomical
features,
was
also
more
predictive
intelligence.
Taken
together,
our
results
add
principle
brain's
organization,
since
is
evident
even
lenient
thresholds.
These
loosely
coupled
further
appear
contain
valuable
potentially
important
information
could
be
understanding
diagnosis,
treatment
outcomes.
Cerebral Cortex,
Journal Year:
2023,
Volume and Issue:
33(17), P. 9718 - 9728
Published: June 28, 2023
Abstract
The
intrinsic
organizational
structure
of
the
brain
is
reflected
in
spontaneous
oscillations.
Its
functional
integration
and
segregation
hierarchy
have
been
discovered
space
by
leveraging
gradient
approaches
to
low-frequency
connectivity.
This
oscillations
has
not
yet
fully
understood,
since
previous
studies
mainly
concentrated
on
from
a
single
limited
frequency
range
(~
0.01–0.1
Hz).
In
this
work,
we
extended
performed
analysis
across
multiple
bands
fast
resting-state
fMRI
signals
Human
Connectome
Project
condensed
frequency-rank
cortical
map
highest
gradient.
We
found
that
coarse
skeletons
organization
are
generalizable
bands.
Beyond
that,
levels
connectivity
vary
domain
different
large-scale
networks.
These
findings
replicated
another
independent
dataset
demonstrated
networks
can
integrate
information
at
varying
rates,
indicating
significance
examining
architecture
activity
perspective
Human Brain Mapping,
Journal Year:
2025,
Volume and Issue:
46(3)
Published: Feb. 15, 2025
While
the
use
of
naturalistic
stimuli
such
as
movie
clips
for
understanding
individual
differences
and
brain-behaviour
relationships
attracts
increasing
interest,
influence
stimulus
selection
remains
largely
unclear.
By
using
machine
learning
to
predict
traits
(phenotypes)
from
brain
activity
evoked
during
various
clips,
we
show
that
different
can
result
in
distinct
prediction
performances.
In
regions
related
lower-level
processing
stimulus,
a
certain
degree
benefits
stronger
synchronisation
across
subjects.
contrast,
better
predictions
frontoparietal
are
mainly
associated
with
larger
inter-subject
variability.
Furthermore,
demonstrate
while
rich
social
content
general
achieve
predictions,
importance
specific
features
highly
depends
on
phenotype
under
investigation.
Overall,
our
findings
underscore
careful
provide
novel
insights
into
conditions,
opening
new
avenues
future
research.
NeuroImage,
Journal Year:
2023,
Volume and Issue:
277, P. 120228 - 120228
Published: June 18, 2023
Functional
gradients,
in
which
response
properties
change
gradually
across
a
brain
region,
have
been
proposed
as
key
organising
principle
of
the
brain.
Recent
studies
using
both
resting-state
and
natural
viewing
paradigms
indicated
that
these
gradients
may
be
reconstructed
from
functional
connectivity
patterns
via
"connectopic
mapping"
analyses.
However,
local
confounded
by
spatial
autocorrelations
artificially
introduced
during
data
analysis,
for
instance
smoothing
or
interpolation
between
coordinate
spaces.
Here,
we
investigate
whether
such
confounds
can
produce
illusory
connectopic
gradients.
We
generated
datasets
comprising
random
white
noise
subjects'
volume
spaces,
then
optionally
applied
and/or
interpolated
to
different
surface
space.
Both
induced
sufficient
mapping
volume-
surface-based
numerous
regions.
Furthermore,
appeared
highly
similar
those
obtained
real
data,
although
were
statistically
certain
scenarios.
also
global
whole-brain
-
while
less
susceptible
artificial
autocorrelations,
ability
reproduce
previously
reported
was
closely
linked
specific
features
analysis
pipeline.
These
results
indicate
identified
techniques
some
cases
poorly
pipelines.
findings
imply
need
interpreted
with
caution.
Brain Sciences,
Journal Year:
2025,
Volume and Issue:
15(3), P. 313 - 313
Published: March 16, 2025
Background/Objectives:
Schizophrenia
is
a
severe
psychiatric
disorder
characterized
by
deficits
in
perception
and
advanced
cognitive
functions.
Prior
studies
have
reported
abnormal
lateralization
cortical
morphology
functional
connectivity
schizophrenia.
However,
it
remains
unclear
whether
schizophrenia
affects
hemispheric
asymmetry
the
hierarchical
organization
of
connectome.
Methods:
Here,
we
apply
gradient
mapping
framework
to
connectome
estimate
first
three
gradients,
which
characterize
unimodal-to-transmodal,
visual-to-somatomotor,
somatomotor/default
mode-to-multiple
demand
hierarchy
axes.
We
then
assess
between-group
differences
intra-
inter-hemispheric
asymmetries
these
gradients.
Results:
find
that,
compared
healthy
controls,
patients
with
exhibit
significantly
altered
across
multiple
networks,
including
dorsal
attention,
ventral
visual,
control
networks.
Region-level
analyses
further
reveal
that
show
several
regions
prefrontal
gyrus,
medial
superior
frontal
somatomotor
areas.
Lastly,
gradients
can
differentiate
between
controls
predict
severity
positive
symptoms
Conclusions:
Collectively,
findings
suggest
associated
hierarchy,
providing
novel
perspectives
for
understanding
atypical
brain
ABSTRACT
Aims
The
gradient
captures
the
continuous
transitions
in
connectivity,
representing
an
intrinsic
hierarchical
architecture
of
brain.
Previous
works
hinted
at
dynamics
but
did
not
verify
them.
Cognitive
impairment
is
a
common
comorbidity
temporal
lobe
epilepsy
(TLE).
Gradient
techniques
provide
framework
that
could
promote
understanding
neural
correlations
cognitive
decline.
Methods
Thirty
patients
with
TLE
and
hippocampal
sclerosis
29
matched
healthy
controls
(HC)
were
investigated
verbal
fluency
task‐based
functional
MRI
techniques.
correlation
between
activation/deactivation
gradients,
dynamic
features
calculated
sliding
window
approaches
was
compared
HC
TLE.
Results
allegiance
real
data
more
widespread
to
static
null
models.
has
lower
recruitment
gradient,
atypical
activation‐gradient
correlation,
contracted
principal
gradient.
Correlation
analysis
proved
reconfiguration
drive
reorganization
activation.
activation
pattern
impaired
correlated
cognition
scales
Discussion
dynamic.
disrupted
patterns,
which
Heliyon,
Journal Year:
2024,
Volume and Issue:
10(9), P. e30194 - e30194
Published: April 24, 2024
BackgroundAuditory
Verbal
Hallucinations
(AVH)
constitute
a
prominent
feature
of
schizophrenia.
Although
low-frequency
repetitive
transcranial
magnetic
stimulation
(rTMS)
has
demonstrated
therapeutic
benefits
in
ameliorating
AVH,
the
foundation
mechanisms
its
efficacy
necessitate
further
elucidation.ObjectiveThis
study
investigate
cortical
gradient
characteristics
and
their
associations
with
clinical
responses
schizophrenia
patients
mediated
through
1
Hz
rTMS
targeting
left
temporoparietal
junction.MethodFunctional
metrics
were
employed
to
examine
hierarchy
patterns
organization,
capturing
whole-brain
functional
connectivity
profiles
controls.ResultsThe
treatment
effectively
ameliorated
positive
symptoms
patients,
specifically
AVH.
Intimal
evaluations
revealed
expanded
global
distribution
specific
principal
variations
certain
brain
regions
compared
control
cohort.
Following
treatment,
these
divergent
local
showed
signs
normalizing.
Furthermore,
there
was
observed
closer
alignment
between-network
dispersion
among
various
networks
after
including
somatomotor,
attention,
limbic
networks,
indicating
potential
harmonization
functionality.ConclusionLow-frequency
induces
alternations
patterns,
may
serve
as
imaging
markers
elucidate
underpinning
on
AVH