Abstract
Despite
the
well-established
phenomenon
of
improved
memory
performance
through
repeated
learning,
studies
investigating
associated
neural
mechanisms
have
yielded
complex
and
sometimes
contradictory
findings,
direct
evidence
from
human
neuronal
recordings
has
been
lacking.
This
study
employs
single-neuron
with
exceptional
spatial–temporal
resolution,
combined
representational
similarity
analysis,
to
explore
dynamics
within
hippocampus
amygdala
during
learning.
Our
results
demonstrate
that
in
hippocampus,
repetition
enhances
both
specificity
fidelity,
these
features
predicting
learning
times.
Conversely,
exhibits
heightened
fidelity
initial
but
does
not
show
improvement
repetition,
suggesting
functional
specialization
different
stages
repetition.
Specifically,
appears
contribute
sustained
engagement
necessary
for
benefiting
while
may
play
a
role
representation
novel
items.
These
findings
comprehensive
understanding
intricate
interplay
between
brain
regions
processes.
Significance
statement
For
over
century,
how
contributes
enhancement
captivated
researchers,
yet
lacking,
primary
focus
on
neglect
neighboring
amygdala.
Employing
advanced
analytical
techniques,
this
unveils
nuanced
amygdala-hippocampal
circuit
various
The
highlight
hippocampus’s
sustaining
contrasting
amygdala’s
superior
ability
representing
exploration
only
deepens
our
comprehension
intricacies
also
sheds
light
potential
interventions
optimize
European Neuropsychopharmacology,
Год журнала:
2024,
Номер
82, С. 44 - 52
Опубликована: Март 14, 2024
Parvalbumin-expressing
(PV+)
interneurons
represent
one
of
the
most
abundant
subclasses
cortical
interneurons.
Owing
to
their
specific
electrophysiological
and
synaptic
properties,
PV+
are
essential
for
gating
pacing
activity
excitatory
neurons.
In
particular,
critically
involved
in
generating
maintaining
rhythms
gamma
frequency,
which
complex
cognitive
functions.
Deficits
have
been
frequently
reported
postmortem
studies
schizophrenia
patients,
alterations
oscillations
a
prominent
feature
disease.
Here,
I
summarise
main
features
review
clinical
preclinical
linking
developmental
dysfunction
with
pathophysiology
schizophrenia.
Ageing & Longevity,
Год журнала:
2025,
Номер
1.2025, С. 37 - 45
Опубликована: Фев. 11, 2025
Normal
brain
ageing
is
associated
with
a
varying
degree
of
cognitive
impairment.
One
the
early
hypotheses
proposed
to
explain
such
changes
was
“Ca2+
hypothesis
ageing”.
This
review
revisits
this
and
uses
Ca2+
dependency
neuronal
excitability
as
an
integrator
discuss
age-dependent
in
activity
various
systems
mechanisms
that
control
homeostasis.
Amongst
these
systems,
special
attention
given
mitochondrial
involvement
regulation
Ca2+,
fact
functions
induced
during
process
might
represent
fulcrum
between
normal,
physiological
neurodegenerative
processes.
However,
it
important
understand
process,
its
effects
on
function,
multifactorial,
results
from
high
interactions
at
cellular
but
also
tissular
level.
Thus,
homeostasis
are
just
one
element
multifactorial
fabric
underlies
ageing.
Keywords:
central
nervous
system;
ageing,
signalling;
mitochondria;
ageing;
neurodegeneration
Journal of Neuroscience,
Год журнала:
2024,
Номер
44(40), С. e1234242024 - e1234242024
Опубликована: Окт. 2, 2024
When
exposed
to
rhythmic
stimulation,
the
human
brain
displays
activity
across
sensory
modalities
and
regions.
Given
ubiquity
of
this
phenomenon,
how
rhythms
are
transformed
into
neural
remains
surprisingly
inconclusive.
An
influential
model
posits
that
endogenous
oscillations
entrain
external
rhythms,
thereby
encoding
environmental
dynamics
shaping
perception.
However,
research
on
entrainment
faces
multiple
challenges,
from
ambiguous
definitions
methodological
difficulties
when
need
be
identified
disentangled
other
stimulus-related
mechanisms
can
lead
similar
phase-locked
responses.
Yet,
recent
years
have
seen
novel
approaches
overcome
these
including
computational
modeling,
insights
dynamical
systems
theory,
sophisticated
stimulus
designs,
study
neuropsychological
impairments.
This
review
outlines
key
challenges
in
research,
delineates
state-of-the-art
approaches,
integrates
findings
animal
neurophysiology
provide
a
broad
perspective
usefulness,
validity,
constraints
oscillatory
models
brain-environment
interaction.
Episodic
memory
relies
on
the
formation
and
retrieval
of
content-specific
traces.
In
addition
to
their
veridical
reactivation,
previous
studies
have
indicated
that
traces
may
undergo
substantial
transformations.
However,
exact
time
course
regional
distribution
reinstatement
transformation
during
recognition
remained
unclear.
We
applied
representational
similarity
analysis
human
intracranial
electroencephalography
track
spatiotemporal
dynamics
underlying
Specifically,
we
examined
how
item-specific
representations
across
occipital,
ventral
visual,
lateral
parietal
cortices
contribute
successful
recognition.
Our
findings
suggest
in
temporal
cortex
coexist
provide
complementary
strategies
for
Further,
find
generalization
differentiation
neural
probe
memory-specific
correspondence
with
deep
network
(DNN)
model
features.
results
is
particularly
supported
by
generalized
mnemonic
formats
beyond
visual
features
a
DNN.
Frontiers in Physiology,
Год журнала:
2024,
Номер
14
Опубликована: Янв. 9, 2024
Environmental
rhythms
such
as
the
daily
light-dark
cycle
selected
for
endogenous
clocks.
These
clocks
predict
regular
environmental
changes
and
provide
basis
well-timed
adaptive
homeostasis
in
physiology
behavior
of
organisms.
Endogenous
are
oscillators
that
based
on
positive
feedforward
negative
feedback
loops.
They
generate
stable
even
under
constant
conditions.
Since
weak
interactions
between
allow
autonomous
synchronization,
coupling/synchronization
provides
self-organized
physiological
timing.
Amongst
most
thoroughly
researched
circadian
clock
neurons
mammals
insects.
comprise
nuclear
clockworks
transcriptional/translational
loops
(TTFL)
∼24
h
gene
expression
entrained
to
day-night
cycle.
It
is
generally
assumed
this
TTFL
clockwork
drives
all
oscillations
within
cells,
being
any
rhythm
Instead
current
gene-based
hierarchical
model
we
here
a
systems
view
We
suggest
coupled
system
posttranslational
loop
(PTFL)
oscillators/clocks
run
at
multiple
timescales
governs
adaptive,
dynamic
behavior.
focus
mammalian
insect
timescales.
neuronal
plasma
membrane-associated
signalosomes
constitute
specific
PTFL
localized
but
interlinked
membrane
potential
intracellular
messengers
with
frequencies.
In
each
neuron
multiscale
form
temporally
structured
oscillatory
network
common
complex
frequency-band
comprising
superimposed
oscillations.
Coupling
oscillator/clock
next
level
complexity
an
network.
This
systemic
molecular
cellular
suggested
cycles
through
homeostatic
setpoints
characteristic
hallmark.
propose
mechanisms
plasticity
maintain
stability
these
setpoints,
whereas
Hebbian
enables
switching
via
coupling
factors,
like
biogenic
amines
and/or
neuropeptides.
reprogram
new
frequency,
setpoint.
Our
novel
hypothesis
up
experimental
challenge.
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 2, 2025
Abstract
Solriamfetol
[(R)-2-amino-3-phenylpropylcarbamate
hydrochloride],
a
phenylalanine
derivative
initially
developed
as
potential
antidepressant,
was
shown
by
our
group
in
2009
to
have
potent,
dose-dependent
wake-promoting
activity
mice.
(Sunosi
®
)
is
used
since
2019
counteract
excessive
daytime
sleepiness
(EDS)
patients
with
narcolepsy
and
obstructive
sleep
apnea
(OSA).
It
has
several
advantages
over
other
stimulants,
notably
that
it
not
associated
strong
psychomotor
activity,
does
induce
behavioral
stereotypies
anxiety-related
behaviors,
contrast
amphetamines
modafinil.
Its
mode-of-action
remains
incompletely
solved.
reported
act
dual
dopamine-and-noradrenaline-reuptake-inhibitor
(DNRI),
more
recently,
TAAR1
agonist
activity.
In
early
mouse
study,
we
showed
that,
at
150
mg/kg,
induces
state
of
wakefulness
featuring
dramatic
upregulation
EEG
gamma
cognitive
biomarker,
the
expression
genes
implicated
neural
plasticity,
learning
memory.
Besides
being
prescribed
treat
EDS,
central
nervous
system
stimulants
are
commonly
‘smart
drugs’
enhance
cognition
normal
individuals.
Therefore,
based
on
Solriamfetol’s
ability
potently
wakefulness,
molecular
markers
memory,
aimed
determine
whether
could
improve
performance
wild-type
Because
doses
50-150
induced
an
alert
waking
low
mobility,
thus
precluding
testing,
lower
(1-3
mg/kg)
assess
battery
tests
evaluating
short-
or
long-term
memory
spatial
navigation.
We
found
compared
saline,
3
mg/kg
consistently
improves
sustained
attention
for
novel
object,
well
Next,
brain
correlates
enhanced
cognition,
performed
EEG/EMG
recording
while
mice
object
recognition
(NOR)
task.
Power
spectral
density
(PSD)
analysis
revealed
reduced
delta
(an
index
sleepiness)
during
exposure
context,
fast-gamma
mental
concentration)
execution
NOR
Taken
together,
data
demonstrate
low-dose
attentional
Communications Biology,
Год журнала:
2025,
Номер
8(1)
Опубликована: Янв. 18, 2025
During
spatial
learning,
subjects
progressively
adjust
their
navigation
strategies
as
they
acquire
experience.
The
medial
prefrontal
cortex
(mPFC)
supports
this
operation,
for
which
it
may
integrate
information
from
distributed
networks,
such
the
hippocampus
(HPC)
and
posterior
parietal
(PPC).
However,
mechanism
underlying
coordination
with
HPC
PPC
during
learning
is
poorly
understood.
Here
we
show
that
trials,
mice
displayed
two
sequential
behavioral
stages:
searching
exploration.
Exclusively
searching,
gradually
increased
efficiency
by
transitioning
non-spatial
to
strategies.
When
used
specifically
in
stage,
hippocampal
oscillations
synchronized
gamma
(60-100
Hz)
neuronal
firing
mPFC.
This
coincided
an
increase
incidence
of
task-stage-related
changes
patterns
These
findings
relate
goal-directed
organization
behavior
transient
task-related
large-scale
synchronization.
In
vivo
neural
activity
recordings
reveal
coupling
modulated
task
requirements
strategy
learning.
Non-invasive
brain
stimulation
techniques
have
the
potential
to
improve
memory
functions.
However,
results
so
far
been
relatively
modest
and
time-consuming.
Here,
we
implemented
a
novel
3-minute
combination
of
personalized
repetitive
transcranial
magnetic
(intermittent
theta
burst-iTBS)
coupled
with
simultaneous
application
gamma
alternating
current
(γtACS)
over
precuneus,
area
connected
hippocampus,
modulate
long
term
in
healthy
subjects.
Only
dual
electromagnetic
precuneus
produced
consistent
increase
long-term
associative
as
compared
iTBS
alone
sham
conditions
sample
volunteers.
The
effects
were
replicated
another
independent
sample,
which
increased
was
retained
for
up
one
week.
Moreover,
oscillations
precuneus-hippocampus
functional
connectivity
through
white
matter
tracts
linking
temporal
lobe.
These
findings
show
that
may
lead
neuronal
assemblies
state
favorable
enhance
plasticity
identify
key
involved
formation.
Personalized
network
represent
new
powerful
approach
enhancing
functions
several
clinical
conditions.
Non-invasive
brain
stimulation
techniques
have
the
potential
to
improve
memory
functions.
However,
results
so
far
been
relatively
modest
and
time-consuming.
Here,
we
implemented
a
novel
3-minute
combination
of
personalized
repetitive
transcranial
magnetic
(intermittent
theta
burst-iTBS)
coupled
with
simultaneous
application
gamma
alternating
current
(γtACS)
over
precuneus,
area
connected
hippocampus,
modulate
long
term
in
healthy
subjects.
Only
dual
electromagnetic
precuneus
produced
consistent
increase
long-term
associative
as
compared
iTBS
alone
sham
conditions
sample
volunteers.
The
effects
were
replicated
another
independent
sample,
which
increased
was
retained
for
up
one
week.
Moreover,
oscillations
precuneus-hippocampus
functional
connectivity
through
white
matter
tracts
linking
temporal
lobe.
These
findings
show
that
may
lead
neuronal
assemblies
state
favorable
enhance
plasticity
identify
key
involved
formation.
Personalized
network
represent
new
powerful
approach
enhancing
functions
several
clinical
conditions.