It's all a Network: Specific Cell Types Influence Seizure Dynamics Across Spatial Areas
Epiliepsy currents/Epilepsy currents,
Год журнала:
2025,
Номер
unknown
Опубликована: Май 11, 2025
Cell-Type-Specific
Networks
During
Hippocampal
Seizures
at
the
Micro-
and
Macroscale
Wang
J,
Yan
Li
D,
He
S,
X,
Xing
Y,
Lai
H,
Gui
Zhang
N,
Huang
W,
Yang
X.
Brain
.
2025:awaf024.
PMID:
39847527
Epilepsy
is
a
network
disorder,
involving
neural
circuits
both
micro-
macroscale.
While
local
excitatory–inhibitory
imbalances
are
recognized
as
hallmark
microscale,
dynamic
role
of
distinct
neuron
types
during
seizures
remain
poorly
understood.
At
macroscale,
interactions
between
key
nodes
within
epileptic
network,
such
central
median
thalamic
nucleus
(CMT),
critical
to
hippocampal
process.
However,
precise
mechanisms
underlying
these
unclear.
In
this
study,
we
investigated
microcircuit
dynamics
seizure
onset
zone
secondary
spreading
regions,
well
connectivity
hippocampus
CMT,
using
4-aminopyridine
(4-AP)
induced
model.
Rats
were
allocated
into
three
experimental
groups.
The
first
group
used
3D
tetrode
array
monitor
activity
dynamics,
including
propagation
across
macroscale
network.
second
group,
chemical
lesion
was
in
CMT
assess
its
impact
on
seizures.
third
chemogenetic
techniques
selectively
suppress
pyramidal
neurons
observe
changes
Offline
single-unit
sorting
performed
KlustaKwik
further
analysis
conducted
with
CellExplorer.
onset,
narrow
interneurons
exhibited
increased
firing
rates,
initiating
recruitment
other
neurons,
followed
by
neuron.
Wide
also
showed
heightened
subsequent
neurons.
Interneurons
played
more
prominent
compared
baseline.
characteristic
decrease
interneuron
activity,
whereas
cortex
did
not
display
Lesioning
resulted
loss
tonic
component
reduced
overall
neuronal
hippocampal.
Selective
suppression
shortened
while
preserving
component.
Narrow
remained
unchanged,
wide
significantly
decreased.
Our
findings
underscore
micronetwork
region.
particularly
vital
initiation,
may
contribute
termination
but
Pyramidal
influence
modulating
interneurons.
Язык: Английский
Oscillatory and nonoscillatory sleep electroencephalographic biomarkers of the epileptic network
Epilepsia,
Год журнала:
2024,
Номер
65(10), С. 3038 - 3051
Опубликована: Авг. 24, 2024
In
addition
to
the
oscillatory
brain
activity,
nonoscillatory
(scale-free)
components
of
background
electroencephalogram
(EEG)
may
provide
further
information
about
complexity
underlying
neuronal
network.
As
epilepsy
is
considered
a
network
disease,
such
scale-free
metrics
might
help
delineate
epileptic
Here,
we
performed
an
analysis
sleep
(spindle,
slow
wave,
and
rhythmic
spectral
power)
(H
exponent)
intracranial
EEG
using
multiple
interictal
features
estimate
whether
how
they
deviate
from
normalcy
in
38
adults
with
drug-resistant
epilepsy.
Язык: Английский
Stable Yet Destabilised: Towards Understanding Brain Network Dynamics in Psychogenic Disorders
Journal of Clinical Medicine,
Год журнала:
2025,
Номер
14(3), С. 666 - 666
Опубликована: Янв. 21, 2025
Background:
Psychogenic
non-epileptic
seizures
(PNES)
are
seizure-like
episodes
that
resemble
behavioral
aspects
observed
for
epileptic
but
without
the
abnormal
electrical
activity
typically
seen
in
epilepsy.
The
lack
of
an
etiologic
model
PNES
as
well
limitations
available
diagnostic
methods
largely
hinders
a
clear-cut
distinction
from
epilepsy
and
normal
functioning
brain.
Methods:
In
this
study,
we
investigate
brain
dynamics
people
with
during
phases
far-off
events
control
group.
Probing
differences
between
these
groups,
utilise
network
ansatz
explore
local
global
characteristics
time-evolving
functional
networks.
We
observe
subject-specific
across
highlighting
physiological
specific
regions.
Furthermore,
significant
characteristics—relating
to
communication,
robustness,
stability
Conclusions:
Our
findings
may
provide
new
insights
into
mechanisms
underlying
offer
promising
approach
differentiate
them
Язык: Английский
EEG signal dimension is an index of seizure propensity and antiseizure medication effects in a mouse model of acquired epilepsy
Epilepsia,
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 9, 2025
Abstract
Objective
Variability
in
the
frequency,
timing,
and
pattern
of
seizures
may
influence
assessment
effect
antiseizure
medications
(ASMs)
when
measuring
seizure
especially
patients
with
infrequent
seizures.
A
low
rate
is
an
exclusion
criterion
for
enrollment
epilepsy
clinical
trials
requires
prolonged
periods
monitoring,
thus
delaying
appropriate
treatment
interventions.
We
investigated
whether
electroencephalogram
(EEG)–based
complexity
measure
susceptibility
epileptic
mice
provides
a
reliable
alternative
to
frequency
evaluating
efficacy
ASMs.
Methods
used
mouse
model
acquired
characterized
by
variability
over
time
among
mice,
as
observed
humans.
analyzed
EEG
recordings
from
chronic
(
n
=
106)
at
baseline
during
phenobarbital,
valproate,
carbamazepine,
or
phenytoin.
recurrence
quantification
analysis
detect
increased
autocorrelation
critical
slowing‐down,
two
signatures
criticality
that
together
contribute
estimate
dimension
phase–space
signals.
The
measurements
were
compared
proxies
correlation
tests
evaluation
ASM
efficacy.
Results
Dimension
provided
statistically
robust
(inverse)
including
no
observation
periods.
In
contrast,
only
high
rate.
Consistently,
using
variations
accurately
reproduced
responsiveness
patterns
this
model.
Significance
EEG‐based
propensity
experience
well
efficacy,
regardless
rates.
Measuring
variation
should
facilitate
inclusion
subjects
preclinical
while
also
shortening
monitoring.
This
could
accelerate
both
development
new
treatments
therapeutic
decisions
medical
field.
Язык: Английский
Preictal connectivity dynamics: Exploring inflow and outflow in iEEG networks
Amirhossein Jahani,
Camille Begin,
Denahin H. Toffa
и другие.
Frontiers in Network Physiology,
Год журнала:
2025,
Номер
5
Опубликована: Апрель 28, 2025
Focal
resective
surgery
can
be
an
effective
treatment
option
for
patients
with
refractory
epilepsy
if
the
seizure
onset
zone
is
accurately
identied
through
intracranial
EEG
recordings.
The
traditional
concept
of
epileptogenic
has
expanded
to
notion
network,
emphasizing
role
interconnected
brain
regions
in
generation.
Precise
delineation
this
network
essential
optimizing
surgical
outcomes.
Over
past
3
decades,
several
quantitative
connectivity
methods
have
been
developed
study
interactions
between
and
non-involved
regions.
Despite
these
advances,
mechanisms
governing
transition
from
interictal
ictal
periods
remain
poorly
understood.
In
study,
we
investigated
preictal
broader
using
directed
measures.
We
evaluated
their
effectiveness
identifying
zones
a
multicenter
dataset,
encompassing
243
seizures
61
patients.
Directed
transfer
function
partial
coherence
were
used
extract
matrices
during
28-seconds
period
good
Inflow
outflow
metrics
computed
iEEG
electrode
contact
annotated
as
performance
each
metric
assessed
disentangling
electrodes
rest
network.
observed
two
distinct
patterns
preceding
onset.
While
there
was
increase
inflow
information
one
subset
patients,
other
subset,
prominent
suggesting
associated
across
Further
analyses
showed
that
who
underwent
grid/strip/depth
implantation
approach
exhibited
significantly
higher
area
under
curve
(AUC)
than
those
electrocorticography
(ECoG)
or
stereo-electroencephalography
(sEEG)
alone.
Finally,
examining
influence
lesional
vs
non-lesional
neuroimaging
status
demonstrated
greater
proportion
high-inflow
high-outflow
lesional.
Our
findings
reinforce
generation
driven
by
dynamic
shifts
flow
within
brain's
functional
--either
increased
high
it
--underscore
reorganization
involved
epileptic
transitions.
These
results
emphasize
network-level
phenomenon,
supporting
use
concepts
better
understanding
dynamics
improving
localization
strategies.
Язык: Английский
Emergence of a tipping subnetwork during a critical transition in networked systems: A new avenue to extreme events
Physical Review Research,
Год журнала:
2025,
Номер
7(2)
Опубликована: Май 1, 2025
Unexpected
and
often
irreversible
shifts
in
the
state
or
dynamics
of
a
complex
system
accumulate
extreme
events
with
likely
disastrous
impact
on
its
environment.
Detection,
understanding,
possible
prediction
such
critical
transitions
are
thus
paramount
importance
across
variety
scientific
fields.
The
rather
modest
improvement
achieved
so
far
may
be
due
previous
research
mostly
concentrating
either
particular
subsystems,
considered
to
vital
for
generating
mechanism
transition,
as
whole.
These
approaches
only
rarely
take
into
account
intricate,
time-dependent
interrelatedness
subsystems
that
can
essentially
determine
emerging
behaviors
underlying
transitions.
We
uncover
network
vertices,
certain
edges,
tipping
elements
networked
dynamical
system,
forming
time-evolving
subnetwork.
demonstrate
existence
subnetworks
excitable
networks
human
epileptic
brains.
systems
repeatedly
undergo
result
events.
Our
findings
reveal
encapsulate
key
properties
mechanisms
involved
Published
by
American
Physical
Society
2025
Язык: Английский
Resting state connectivity biomarkers of seizure freedom after epilepsy surgery
NeuroImage Clinical,
Год журнала:
2024,
Номер
44, С. 103673 - 103673
Опубликована: Янв. 1, 2024
Alterations
in
brain
networks
may
cause
the
lowering
of
seizure
threshold
and
hypersynchronization
that
underlie
recurrence
unprovoked
seizures
epilepsy.
The
aim
this
work
is
to
estimate
functional
network
characteristics,
which
help
predicting
outcome
epilepsy
surgery.
Twenty
patients
were
studied
(11
females,
9
males,
mean
age
33
years)
with
scalp-recorded
HD-EEG
resting
state
(eyes
closed,
no
interictal
discharges)
before
intracranial
evaluation,
allowed
precise
determination
epileptogenic
zone.
Dipole
source
time
courses
estimated
using
Weighted
Minimum
Norm
Estimate
based
on
signals.
Information
inflow
outflow
atlas-based
regions
computed
partial
directed
connectivity.
A
set
graph
measures
for
pairwise
connections
standard
EEG
frequency
bands
was
calculated.
After
surgery
10
seizure-free
(Engel
1a)
continued
suffering
from
worse
than
1a).
Inflow
containing
zone
beta
delta
significantly
lower
who
achieved
seizure-freedom
after
surgery,
compared
have
(p
=
0.012,
p
0.026,
respectively).
Average
path
length
band
higher
freedom
0.012).
In
band,
local
efficiency
clustering
coefficient
(0.033,
0.046).
preoperative
analysis
epileptic
exhibited
stronger
separation
region
onset
zone,
less
information.
contrast,
shorter
paths
within
facilitate
hypersynchronous
neuronal
activity
thus
non-seizure
free
patients.
This
study
supports
hypothesis
properties
might
define
suitable
candidates
Язык: Английский
Modeling seizure networks in neuron-glia cultures using microelectrode arrays
Frontiers in Network Physiology,
Год журнала:
2024,
Номер
4
Опубликована: Сен. 3, 2024
Epilepsy
is
a
common
neurological
disorder,
affecting
over
65
million
people
worldwide.
Unfortunately,
despite
resective
surgery,
30
%
of
patients
with
drug-resistant
epilepsy
continue
to
experience
seizures.
Retrospective
studies
considering
connectivity
using
intracranial
electrocorticography
(ECoG)
obtained
during
neuromonitoring
have
shown
that
treatment
failure
likely
driven
by
consider
critical
components
the
seizure
network,
an
idea
first
formally
introduced
in
2002.
However,
current
only
capture
snapshots
time,
precluding
ability
network
development.
Over
past
few
years,
multiwell
microelectrode
arrays
been
increasingly
used
study
neuronal
networks
vitro
.
As
such,
we
sought
develop
novel
MEA
model
allow
for
networks.
Specifically,
4-aminopyridine
(4-AP)
hyperexcitable
activity,
and
then
show
increased
changes
after
2
days
chronic
treatment.
We
characterize
functional
measures
technique
dimensionality
reduction.
find
4-AP
successfully
captures
persistently
elevated
mean
firing
rate
significant
underlying
patterns.
believe
this
affords
robust
from
which
longitudinal
can
be
studied,
laying
groundwork
future
exploring
Язык: Английский
Brivaracetam and rufinamide combination increased seizure threshold and improved neurobehavioral deficits in corneal kindling model of epilepsy
Animal Models and Experimental Medicine,
Год журнала:
2024,
Номер
unknown
Опубликована: Окт. 22, 2024
Abstract
Background
Besides
seizures,
a
myriad
of
overlapping
neuropsychiatric
and
cognitive
comorbidities
occur
in
patients
with
epilepsy,
which
further
debilitates
their
quality
life.
This
study
provides
an
in‐depth
characterization
the
impact
brivaracetam
rufinamide
individually
combination
at
10
20
mg/kg
doses,
respectively,
on
corneal
kindling‐induced
generalized
seizures
behavioral
alterations.
Furthermore,
observed
convulsive
frequency
changes
were
correlated
to
post‐kindling‐induced
activity
markers
oxidative
stress.
Methods
Adult
C57BL/6
mice
kindled
via
twice‐daily
transcorneal
50‐Hz
electrical
stimulations
(3
mA)
for
3
s
12
days
until
animals
reached
fully
state.
After
kindling
procedure,
tested
using
set
tests,
neurochemical
alterations
assessed.
Results
Corneal‐kindled
exhibited
intense
convulsions,
altered
phenotypes
typified
by
positive
symptoms
(hyperlocomotion),
negative
(anxiety
anhedonia),
deficits
semantic
working
memory.
BRV
+
RFM
dual
regime
increased
threshold
propensity
toward
start
stage
4–5
improved
phenotypical
deficits,
that
is,
anxiety,
depression,
memory
impairments.
Moreover,
this
therapy
mitigated
redox
impairments
as
evidenced
reduced
malondialdehyde
acetylcholinesterase
levels
glutathione
antioxidant
brain
subjected
repetitive
insult.
Conclusion
Based
our
outcomes,
supporting
evidence
alleviating
epilepsy‐induced
neurobehavioral
homeostasis.
Язык: Английский