An
autorhythmic
population
of
excitatory
neurons
in
the
brainstem
pre-Bötzinger
complex
is
a
critical
component
mammalian
respiratory
oscillator.
Two
intrinsic
neuronal
biophysical
mechanisms—a
persistent
sodium
current
(INaP)
and
calcium-activated
non-selective
cationic
xmlns:mml="http://www.w3.org/1998/Math/MathML">ICAN)—were
proposed
to
individually
or
combination
generate
cellular-
circuit-level
oscillations,
but
their
roles
are
debated
without
resolution.
We
re-examined
these
model
synaptically
connected
with
ICAN
xmlns:mml="http://www.w3.org/1998/Math/MathML">INaP.
This
robustly
reproduces
experimental
data
showing
that
rhythm
generation
can
be
independent
activation,
which
determines
activity
amplitude.
occurs
when
primarily
activated
by
calcium
fluxes
driven
synaptic
mechanisms.
Rhythm
depends
critically
on
xmlns:mml="http://www.w3.org/1998/Math/MathML">INaP
subpopulation
forming
rhythmogenic
kernel.
The
explains
how
amplitude
oscillations
involve
distinct
Frontiers in Computational Neuroscience,
Год журнала:
2020,
Номер
14
Опубликована: Июнь 8, 2020
In
this
paper,
we
focus
on
the
emergence
of
diverse
neuronal
oscillations
arising
in
a
mixed
population
neurons
with
different
excitability
properties.
These
properties
produce
mode
(MMOs)
characterized
by
combination
large
amplitudes
and
alternate
subthreshold
or
small
amplitude
oscillations.
Considering
biophysically
plausible,
Izhikevich
neuron
model,
demonstrate
that
various
MMOs,
including
MMBOs
(mixed
bursting
oscillations)
synchronized
tonic
spiking
appear
randomly
connected
network
neurons,
where
fraction
them
is
quiescent
(silent)
state
rest
self-oscillatory
(firing)
states.
We
show
MMOs
other
patterns
neural
activity
depend
number
oscillatory
neighbors
nodes
electrical
coupling
strengths.
Our
results
are
verified
constructing
reduced-order
model
supported
systematic
bifurcation
diagrams
as
well
for
small-world
network.
suggest
that,
weak
couplings,
due
to
de-synchronization
networks.
The
together
firing
high
frequency
activity.
overarching
goal
uncover
favorable
architecture
suitable
parameter
spaces
generate
responses
ranging
from
spiking.
Physical review. E,
Год журнала:
2021,
Номер
104(2)
Опубликована: Авг. 12, 2021
Mixed-mode
oscillations
(MMOs)
are
a
complex
dynamical
behavior
in
which
each
cycle
of
oscillation
consists
one
or
more
large
amplitude
spikes
followed
by
small
peaks.
MMOs
typically
undergo
period-adding
bifurcations
under
parameter
variation.
We
demonstrate
here,
set
three
identical,
linearly
coupled
van
der
Pol
oscillators,
scenario
exhibit
period-doubling
sequence
to
chaos
that
preserves
the
MMO
structure,
as
well
bifurcations.
characterize
chaotic
nature
and
attribute
their
existence
master-slave-like
forcing
inner
oscillator
outer
two
with
sufficient
phase
difference
between
them.
Simulations
single
nonautonomous
forced
sine
functions
support
this
interpretation
suggest
may
be
general.
PLoS Computational Biology,
Год журнала:
2020,
Номер
16(11), С. e1008430 - e1008430
Опубликована: Ноя. 9, 2020
Epilepsy
is
a
dynamic
and
complex
neurological
disease
affecting
about
1%
of
the
worldwide
population,
among
which
30%
patients
are
drug-resistant.
characterized
by
recurrent
episodes
paroxysmal
neural
discharges
(the
so-called
seizures),
manifest
themselves
through
large-amplitude
rhythmic
activity
observed
in
depth-EEG
recordings,
particular
local
field
potentials
(LFPs).
The
signature
characterizing
transition
to
seizures
involves
oscillatory
patterns,
could
serve
as
marker
prevent
seizure
initiation
triggering
appropriate
therapeutic
neurostimulation
methods.
To
investigate
such
protocols,
neurophysiological
lumped-parameter
models
at
mesoscopic
scale,
namely
mass
models,
powerful
tools
that
not
only
mimic
LFP
signals
but
also
give
insights
on
mechanisms
related
different
stages
seizures.
Here,
we
analyze
multiple
time-scale
dynamics
model
explain
underlying
structure
oscillations
before
initiation.
We
population-specific
effects
stimulation
dependence
parameters
synaptic
timescales.
In
particular,
show
intermediate
frequencies
(>20
Hz)
can
abort
if
timescale
difference
pronounced.
Those
results
have
potential
design
brain
protocols
based
properties
tissue.
Journal of Neuroscience,
Год журнала:
2022,
Номер
43(2), С. 240 - 260
Опубликована: Ноя. 18, 2022
The
preBötzinger
Complex
(preBötC)
encodes
inspiratory
time
as
rhythmic
bursts
of
activity
underlying
each
breath.
Spike
synchronization
throughout
a
sparsely
connected
preBötC
microcircuit
initiates
that
ultimately
drive
the
motor
patterns.
Using
minimal
models
to
explore
burst
initiation
dynamics,
we
examined
variability
in
probability
and
latency
following
exogenous
stimulation
small
subset
neurons,
mimicking
experiments.
Among
various
physiologically
plausible
graphs
1000
excitatory
neurons
constructed
using
experimentally
determined
synaptic
connectivity
parameters,
directed
Erdős-Rényi
with
broad
(lognormal)
distribution
weights
best
captured
observed
dynamics.
leading
was
regulated
by
efferent
spiking
are
optimally
tuned
amplify
modest
preinspiratory
through
input
convergence.
graph-theoretic
machine
learning-based
analyses,
found
convergence
at
next-nearest
neighbor
order
strong
predictor
incipient
synchronization.
Our
analyses
revealed
crucial
role
heterogeneity
imparting
exceptionally
robust
yet
flexible
attractor
Given
pervasiveness
lognormally
distributed
strengths
nervous
system,
postulate
these
mechanisms
represent
ubiquitous
template
for
temporal
processing
decision-making
computational
motifs.
SIGNIFICANCE
STATEMENT
Mammalian
breathing
is
robust,
virtually
continuous
life,
inherently
labile:
adapt
rapid
metabolic
shifts
(e.g.,
fleeing
predator
or
chasing
prey);
airway
reflexes;
enable
nonventilatory
behaviors
vocalization,
breathholding,
laughing).
Canonical
theoretical
frameworks—based
on
pacemakers
intrinsic
bursting—cannot
account
robustness
flexibility
rhythm.
Experiments
reveal
network
key
initiate
cycle.
We
investigated
dynamics
neuronal
parameters.
discovered
fat-tailed
(non-Gaussian)
weight
distribution—a
manifestation
heterogeneity—augments
this
vital
rhythmogenic
network,
contributing
its
extraordinary
reliability
responsiveness.
PLoS Computational Biology,
Год журнала:
2019,
Номер
15(7), С. e1006860 - e1006860
Опубликована: Июль 30, 2019
A
central
issue
in
the
study
of
neural
generation
respiratory
rhythms
is
role
intrinsic
pacemaking
capabilities
that
some
neurons
exhibit.
The
debate
on
this
has
occurred
parallel
to
investigations
interactions
among
network
and
how
these
contribute
behavior.
In
computational
study,
we
demonstrate
two
issues
are
inextricably
linked.
We
use
simulations
dynamical
systems
analysis
show
once
a
conditional
pacemaker,
which
can
be
tuned
across
oscillatory
non-oscillatory
dynamic
regimes
isolation,
embedded
into
network,
its
dynamics
become
masked:
exhibits
similar
properties
regardless
pacemaker
node's
tuning,
outputs
dominated
by
influences.
Furthermore,
pattern
generator
as
whole
invariant
changes
properties,
ensures
flexible
robust
performance
over
wide
range.
Glia,
Год журнала:
2022,
Номер
70(8), С. 1506 - 1519
Опубликована: Фев. 25, 2022
Abstract
Central
pattern
generators
(CPGs)
generate
the
rhythmic
and
coordinated
neural
features
necessary
for
proper
conduction
of
complex
behaviors.
In
particular,
CPGs
are
crucial
motor
behaviors
such
as
locomotion,
mastication,
respiration,
vocal
production.
While
importance
these
networks
in
modulating
behavior
is
evident,
mechanisms
driving
still
not
fully
understood.
On
other
hand,
accumulating
evidence
suggests
that
astrocytes
have
a
significant
role
regulating
function
some
CPGs.
Here,
we
review
location,
function,
mastication
propose
that,
similarly,
may
also
play
vocalization
CPG.
