Chaos An Interdisciplinary Journal of Nonlinear Science,
Год журнала:
2024,
Номер
34(12)
Опубликована: Дек. 1, 2024
We
present
numerical
results
on
the
effects
of
two
presynaptic
FitzHugh–Nagumo
neurons
a
postsynaptic
neuron
under
unidirectional
electrical
coupling.
The
affect
not
simultaneously
but
with
certain
time
shift.
consider
cases
where
amplitudes
spikes
can
be
both
higher
and
lower
than
excitation
threshold
level.
latter
case
receives
main
attention
in
our
work.
carefully
examine
conditions
which
is
excited
by
asynchronous
external
spikes.
With
arbitrarily
chosen
parameters,
almost
incapable
accumulating
energy
signals,
unlike,
for
example,
leaky
integrate-and-fire
neuron.
In
this
case,
only
excites
very
short
delay
between
impulses.
However,
we
have
discovered,
first
time,
parameter
region
possible
even
significant
delays
impulses
subthreshold
amplitudes.
explain
effect
detail
describe
mechanism
behind
its
occurrence.
identify
boundaries
plane
coupling
coefficient
varying
control
values
neurons.
has
previously
been
used
as
node
spiking
neural
networks
training
via
spike-timing-dependent
plasticity
due
to
lack
an
effect.
detection
range
parameters
makes
potential
application
STDP
possible.
Cells,
Год журнала:
2024,
Номер
13(7), С. 573 - 573
Опубликована: Март 26, 2024
Neuronal
timing
with
millisecond
precision
is
critical
for
many
brain
functions
such
as
sensory
perception,
learning
and
memory
formation.
At
the
level
of
chemical
synapse,
synaptic
delay
determined
by
presynaptic
release
probability
(Pr)
waveform
action
potential
(AP).
For
instance,
paired-pulse
facilitation
or
long-term
potentiation
are
associated
reductions
in
delay,
whereas
depression
an
increased
delay.
Parallelly,
AP
broadening
that
results
from
inactivation
voltage
gated
potassium
(Kv)
channels
responsible
repolarization
phase
delays
response,
sodium
(Nav)
reduces
latency.
However,
whether
modulated
during
depolarization-induced
analogue–digital
(d-ADF),
a
form
context-dependent
induced
prolonged
depolarization
neuron
mediated
voltage-inactivation
Kv1
channels,
remains
unclear.
We
show
here
despite
Pr
being
elevated
d-ADF
at
pyramidal
L5-L5
cell
synapses,
surprisingly
unchanged.
This
finding
suggests
both
Pr-
AP-dependent
changes
compensate
each
other
d-ADF.
conclude
that,
contrast
to
short-
modulations
release,
not
affected
because
opposite
interaction
Synaptopodin
(SP),
an
actin-associated
protein
found
in
telencephalic
neurons,
affects
activity-dependant
synaptic
plasticity
and
dynamic
changes
of
dendritic
spines.
While
being
required
for
long-term
depression
(LTD)
mediated
by
metabotropic
glutamate
receptor
(mGluR-LTD),
little
is
known
about
its
role
other
forms
LTD
induced
low
frequency
stimulation
(LFS-LTD)
or
spike-timing
dependent
(STDP).
Using
electrophysiology
ex
vivo
hippocampal
slices
from
SP-deficient
mice
(SPKO),
we
show
that
absence
SP
associated
with
a
deficit
at
Sc-CA1
synapses
LFS-LTD
STDP.
As
to
require
AMPA-
receptors
internalization
IP3-receptors
calcium
signaling,
tested
western
blotting
immunochemistry
if
there
were
their
expression
which
be
reduced.
not
able
induce
LTD,
potentiation
(LTP),
albeit
diminished
SPKO,
can
recovered
using
stronger
protocol.
In
SPKO
no
differences
NMDAR,
are
the
primary
site
signalling
LTP.
Our
study
shows,
first
time,
key
requirement
allow
induction
synapses.
A
central
hypothesis
on
brain
functioning
is
that
plasticity
regulates
the
signals
transfer
function
by
modifying
efficacy
of
synaptic
transmission.
In
cerebellum,
granular
layer
has
been
shown
to
control
gain
transmitted
through
mossy
fiber
pathway.
Until
now,
impact
incoming
activity
patterns
was
analyzed
combining
electrophysiological
recordings
in
acute
cerebellar
slices
and
computational
modeling,
unraveling
a
broad
spectrum
different
forms
layer,
often
along
with
intrinsic
excitability
changes.
Here,
we
attempt
provide
brief
overview
most
prominent
at
excitatory
synapses
formed
fibers
onto
principal
neurons
(granule
cells,
Golgi
cells
unipolar
brush
cells)
layer.
Specifically,
will
highlight
current
understanding
mechanisms
their
functional
implications
plasticity,
providing
valuable
insights
into
how
inputs
are
processed
reconfigured
input
stage.
Frontiers in Neuroscience,
Год журнала:
2024,
Номер
18
Опубликована: Ноя. 14, 2024
General
anesthesia
is
a
widely
used
medical
practice,
affecting
more
than
300
million
patients
annually.
Despite
its
ubiquity,
the
underlying
mechanisms
through
which
anesthetic
agents
induce
amnesia
remain
poorly
understood.
This
review
explores
impact
of
general
anesthetics
on
memory
function,
with
particular
focus
role
neural
oscillations
in
anesthesia-induced
suppression.
Neural
oscillations,
such
as
theta,
gamma,
delta
slow
(SO),
spindles,
and
sharp
wave
ripples
(SWR),
are
critical
for
formation
consolidation.
Various
modulate
these
ways
that
affect
memory,
even
at
subanesthetic
concentrations.
We
highlight
recent
findings
molecular
electrophysiological
by
influence
memory-related
including
inhibition
synaptic
plasticity,
alterations
spike-timing-dependent
plasticity
(STDP),
disruption
cross-frequency
couplings
like
theta-gamma
SO-spindle-SWR.
Additionally,
addresses
significance
age
anesthesia-related
loss,
elderly
being
particularly
vulnerable
to
long-term
cognitive
decline.
Electrophysiological
techniques,
Electroencephalography
(EEG);
advanced
neuromodulation
chemogenetics,
optogenetics,
have
provided
insights
into
dynamics
underpinning
amnesia,
yet
causal
relationship
between
EEG
rhythms
impairment
remains
be
fully
elucidated.
underscores
importance
further
research
interaction
anesthesia,
memory.
Understanding
will
not
only
advance
theoretical
knowledge
but
also
aid
development
safer
strategies
mitigate
postoperative
dysfunction,
especially
high-risk
populations.
Chaos An Interdisciplinary Journal of Nonlinear Science,
Год журнала:
2024,
Номер
34(12)
Опубликована: Дек. 1, 2024
We
present
numerical
results
on
the
effects
of
two
presynaptic
FitzHugh–Nagumo
neurons
a
postsynaptic
neuron
under
unidirectional
electrical
coupling.
The
affect
not
simultaneously
but
with
certain
time
shift.
consider
cases
where
amplitudes
spikes
can
be
both
higher
and
lower
than
excitation
threshold
level.
latter
case
receives
main
attention
in
our
work.
carefully
examine
conditions
which
is
excited
by
asynchronous
external
spikes.
With
arbitrarily
chosen
parameters,
almost
incapable
accumulating
energy
signals,
unlike,
for
example,
leaky
integrate-and-fire
neuron.
In
this
case,
only
excites
very
short
delay
between
impulses.
However,
we
have
discovered,
first
time,
parameter
region
possible
even
significant
delays
impulses
subthreshold
amplitudes.
explain
effect
detail
describe
mechanism
behind
its
occurrence.
identify
boundaries
plane
coupling
coefficient
varying
control
values
neurons.
has
previously
been
used
as
node
spiking
neural
networks
training
via
spike-timing-dependent
plasticity
due
to
lack
an
effect.
detection
range
parameters
makes
potential
application
STDP
possible.