The Journal of Physiology,
Год журнала:
2023,
Номер
602(2), С. 373 - 395
Опубликована: Дек. 12, 2023
Abstract
Parkinson's
disease
is
characterized
by
exaggerated
beta
activity
(13–35
Hz)
in
cortico‐basal
ganglia
motor
loops.
Beta
includes
both
periodic
fluctuations
(i.e.
oscillatory
activity)
and
aperiodic
reflecting
spiking
excitation/inhibition
balance
non‐oscillatory
activity).
However,
the
relative
contribution,
dopamine
dependency
clinical
correlations
of
vs
.
remain
unclear.
We
recorded,
modelled
analysed
subthalamic
local
field
potentials
parkinsonian
patients
at
rest
while
off
or
on
medication.
Autoregressive
modelling
with
additive
1/
f
noise
clarified
relationships
between
measures
time
domain
amplitude
duration
bursts)
frequency
power
sharpness
spectral
peak)
activity:
burst
are
specifically
sensitive
to
activity,
whereas
ambiguously
activity.
Our
experimental
data
confirmed
model
predictions
assumptions.
subsequently
effect
levodopa,
obtaining
strong‐to‐extreme
Bayesian
evidence
that
reduced
medication,
moderate
for
absence
modulation
component.
Finally,
component
correlated
rate
progression
disease.
Methodologically,
these
results
provide
an
integrative
understanding
beta‐based
biomarkers
relevant
adaptive
deep
brain
stimulation.
Biologically,
they
suggest
primarily
dependent
may
play
a
role
not
only
pathophysiology
but
also
image
Key
points
true
synaptic
The
Burst
Only
dopamine‐dependent.
Stronger
correlates
faster
eNeuro,
Год журнала:
2024,
Номер
unknown, С. ENEURO.0242 - 24.2024
Опубликована: Авг. 13, 2024
Generalized
epilepsy
(GE)
encompasses
a
heterogenous
group
of
hyperexcitability
disorders
that
clinically
manifest
as
seizures.
At
the
whole-brain
level,
distinct
seizure
patterns
well
interictal
epileptic
discharges
(IEDs)
reflect
key
signatures
in
magneto-
and
electroencephalographic
(M/EEG)
recordings.
Moreover,
it
had
been
suggested
aperiodic
activity,
specifically
slope
1/ƒ
x
decay
function
power
spectrum,
might
index
neural
excitability.
However,
remained
unclear
if
encountered
at
cellular
level
directly
translates
to
putative
large-scale
excitability
signatures,
amenable
M/EEG.
In
order
test
whether
spectrum
is
altered
hyperexcitable
states,
we
recorded
resting
state
MEG
from
male
female
GE
patients
(n
=
51;
29
females;
28.82
±
12.18
years;
mean
SD)
age-matched
healthy
controls
49;
22
32.10
12.09
years).
We
parametrized
spectra
using
FOOOF
separate
oscillatory
activity
systematically
patients.
further
identified
IEDs
quantify
temporal
dynamics
around
overt
activity.
The
results
demonstrate
indexes
especially
during
epochs
when
no
were
present
(p
0.0130,
d
0.52).
Upon
IEDs,
circuits
transiently
shifted
less
excitable
network
0.001,
0.68).
sum,
these
uncover
background
based
on
current
brain
does
not
rely
presence
waveforms.
Significance
Statement
It
long
suspected
electric
disorders,
such
epilepsy.
To
date,
how
pathologic
can
be
quantified.
Kopf
et
al.
hyperexcitability,
absent;
hence,
providing
novel
non-invasively
biomarker
possibly
reflects
Brain Communications,
Год журнала:
2024,
Номер
6(5)
Опубликована: Янв. 1, 2024
Cognitive
symptoms
in
Parkinson's
disease
are
common
and
can
significantly
affect
patients'
quality
of
life.
Therefore,
there
is
an
urgent
clinical
need
to
identify
a
signature
derived
from
behavioural
and/or
neuroimaging
indicators
that
could
predict
which
patients
at
increased
risk
for
early
rapid
cognitive
decline.
Recently,
converging
evidence
identified
aperiodic
activity
the
EEG
reflects
meaningful
physiological
information
associated
with
age,
development,
perceptual
states
or
pathologies.
In
this
study,
we
aimed
investigate
during
control
characterize
its
possible
association
behaviour.
Here,
recorded
high-density
30
healthy
controls
Simon
task.
We
analysed
task-related
data
context
activation-suppression
model
extracted
parameters
(offset,
exponent)
both
scalp
source
levels.
Our
results
showed
lower
performances
as
well
higher
offsets
parieto-occipital
areas,
suggesting
excitability
disease.
A
small
congruence
effect
on
pre-
post-central
brain
areas
was
also
found,
possibly
task
execution.
Significant
differences
between
resting-state,
post-stimulus
phases
were
seen
across
whole
brain,
confirmed
observed
changes
linked
No
correlation
found
behaviour
features.
findings
provide
characterized
by
greater
offsets,
differ
depending
arousal
state.
However,
our
do
not
support
hypothesis
behaviour-related
related
changes.
Overall,
study
highlights
importance
considering
contributions
disorders
further
investigating
relationship
medRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2024,
Номер
unknown
Опубликована: Окт. 15, 2024
Abstract
In
the
study
of
neuro-electrophysiological
recordings,
aperiodic
neural
activity
–
with
no
characteristic
frequency
has
increasingly
become
a
common
feature
study.
This
interest
rapidly
extended
to
clinical
work,
many
reports
investigating
from
patients
broad
range
disorders.
work
typically
seeks
evaluate
as
putative
biomarker
relating
diagnosis
or
treatment
response,
and/or
potential
marker
underlying
physiological
activity.
There
is
thus
far
clear
consensus
on
if
and
how
relates
disorders,
nor
best
practices
for
it
in
research.
To
address
this,
this
systematic
literature
review,
following
PRISMA
guidelines,
examines
electrophysiological
recordings
human
psychiatric
neurological
finding
143
across
35
distinct
Reports
within
disorders
are
summarized
current
findings
examine
what
can
be
learned
pertains
analysis,
interpretations,
overall
utility
investigations.
Aperiodic
commonly
reported
relate
diagnoses,
31
reporting
significant
effect
diagnostic
related
studies.
However,
there
variation
consistency
results
heterogeneity
patient
groups,
disease
etiologies,
status
arising
themes
different
Overall,
variability
results,
potentially
confounding
covariates,
limitations
understanding
suggests
further
needed
before
established
pathological
physiology.
Finally,
series
recommendations
proposed,
based
findings,
limitations,
key
discussion
topics
assist
guiding
productive
future
studying
Project
Repository
The
project
repository
contains
code
&
data
project:
https://github.com/TomDonoghue/AperiodicClinical
ABSTRACT
The
aperiodic
exponent
of
the
power
spectrum
signals
in
several
neuroimaging
modalities
has
been
found
to
be
related
excitation/inhibition
balance
neural
system.
Leveraging
rich
temporal
dynamics
resting‐state
pupil
fluctuations,
present
study
investigated
association
between
fluctuations
and
attentional
processing.
In
separate
phases,
we
recorded
participants'
size
during
resting
state
assessed
their
orienting
using
Posner
cueing
tasks
with
different
cue
validities
(i.e.,
100%
50%).
We
significant
correlations
both
microsaccadic
behavioral
effects.
Critically,
this
relationship
was
particularly
evident
50%
cue‐validity
condition
rather
than
condition.
responses
mediated
response.
Further
analysis
showed
that
predicted
self‐rated
hyperactivity/impulsivity
trait
across
individuals,
suggesting
its
potential
as
a
marker
deficits.
These
findings
highlight
information
contained
provide
new
approach
assessing
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 27, 2025
Neural
signals
encode
information
through
oscillatory
and
transient
components.
The
component
captures
rapid,
non-rhythmic
changes
in
response
to
internal
or
external
events,
while
the
reflects
rhythmic
patterns
critical
for
processing
sensation,
action,
cognition.
Current
spectral
time-domain
methods
often
struggle
distinguish
two
components,
particularly
under
sharp
transitions,
leading
interference
leakage.
This
study
introduces
a
novel
adaptive
smoothing
algorithm
that
isolates
components
by
dynamically
up-sampling
signal
regions
with
abrupt
changes.
approach
leverages
Euclidean
distance-based
thresholds
refine
sampling
applies
customized
techniques,
preserving
details
minimizing
interference.
Tested
on
both
synthetic
recorded
local
field
potential
data,
outperformed
conventional
handling
steep
as
demonstrated
lower
mean-square
error
improved
separation.
Our
findings
highlight
algorithm's
enhance
neural
analysis
more
accurately
separating
paving
way
precise
characterization
of
dynamics
research
clinical
applications.
Brain stimulation,
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 1, 2025
Mounting
evidence
suggests
the
efficacy
of
neuromodulation
for
epilepsy
is
mediated
by
network
remodeling
and
neural
state.
Epilepsy
related
pathophysiology
has
been
associated
with
variation
in
aperiodic
exponent,
which
describes
inverse
relationship
between
frequency
power
linked
to
synaptic-level
processes.
This
study
sought
assess
relationships
periodic
activity,
disease
state,
responsive
stimulation.
Chronic
intracranial
EEG
was
recorded
from
13
patients
undergoing
neurostimulation
epilepsy.
Recordings
containing
clinician-annotated
seizures,
stimulation
triggered
device-detected
interictal
epileptiform
activity
(IEA),
stimulation-free
periods
were
analyzed.
Multidien
IEA
cycles
identified,
recordings
classified
cycle
phase.
Power
spectra
parameterized
into
components
using
an
established
algorithm.
The
exponent
larger
during
seizures
pre-stimulation
intervals
than
recordings,
decreased
following
A
rise
observed
12
hours
preceding
seizures.
Larger
rising
phase
multidien
cycles.
Periodic
alpha
beta
intervals,
high-risk
(rising
and/or
peak)
phases,
whereas
theta
gamma
exhibited
variable
relationships.
did
not
change
after
or
before
any
studied
band.
positively
instantaneous
state
severity
negatively
therapeutic
Aperiodic
may
emerge
as
a
practical
biomarker
treatment
response
guide