Neocortical-hippocampal
interactions
support
new
episodic
(event)
memories,
but
there
is
conflicting
evidence
about
the
dependence
of
remote
memories
on
hippocampus.
In
line
with
systems
consolidation
and
computational
theories
memory,
from
model
organisms
suggests
that
cornu
ammonis
3
(CA3)
hippocampal
subfield
supports
recent,
not
remote,
retrieval.
this
study,
we
demonstrated
recent
were
susceptible
to
a
loss
detail
in
human
participants
focal
bilateral
damage
CA3.
Graph
theoretic
analyses
7.0-Tesla
resting-state
fMRI
data
revealed
CA3
disrupted
functional
integration
across
medial
temporal
lobe
(MTL)
subsystem
default
network.
The
MTL
regions
was
predictive
autobiographical
retrieval
performance.
We
conclude
necessary
for
long
after
their
initial
acquisition
network
important
memory
Nature Communications,
Год журнала:
2022,
Номер
13(1)
Опубликована: Июль 22, 2022
Abstract
When
we
remember
events,
often
do
not
only
recall
individual
but
also
the
connections
between
them.
However,
extant
research
has
focused
on
how
humans
segment
and
discrete
events
from
continuous
input,
with
far
less
attention
given
to
structure
of
impacts
memory.
Here
conduct
a
functional
magnetic
resonance
imaging
study
in
which
participants
watch
series
realistic
audiovisual
narratives.
By
transforming
narratives
into
networks
demonstrate
that
more
central
events—those
stronger
semantic
or
causal
other
events—are
better
remembered.
During
encoding,
evoke
larger
hippocampal
event
boundary
responses
associated
memory
formation.
recall,
high
centrality
is
activation
cortical
areas
involved
episodic
recollection,
similar
neural
representations
across
individuals.
Together,
these
results
suggest
when
encode
retrieve
complex
real-world
experiences,
reliability
accessibility
shaped
by
their
location
within
network
events.
Nature Communications,
Год журнала:
2022,
Номер
13(1)
Опубликована: Фев. 2, 2022
In
memory,
our
continuous
experiences
are
broken
up
into
discrete
events.
Boundaries
between
events
known
to
influence
the
temporal
organization
of
memory.
However,
how
and
through
which
mechanism
event
boundaries
shape
order
memory
(TOM)
remains
unknown.
Across
four
experiments,
we
show
that
exert
a
dual
role:
improving
TOM
for
items
within
an
impairing
across
Decreasing
length
in
list
enhances
TOM,
but
only
at
earlier
local
positions,
effect
term
primacy
effect.
A
computational
model,
associated
context
signal
drifts
over
time
resets
captures
all
behavioural
results.
Our
findings
provide
unified
algorithmic
understanding
why
affect
reconciling
long-standing
paradox
both
contextual
similarity
dissimilarity
promote
TOM.
Proceedings of the National Academy of Sciences,
Год журнала:
2022,
Номер
119(43)
Опубликована: Окт. 17, 2022
How
infants
experience
the
world
is
fundamental
to
understanding
their
cognition
and
development.
A
key
principle
of
adult
that,
despite
receiving
continuous
sensory
input,
we
perceive
this
input
as
discrete
events.
Here
investigate
such
event
segmentation
in
how
it
differs
from
adults.
Research
on
often
uses
simplified
tasks
which
(adult)
experimenters
help
solve
problem
for
by
defining
boundaries
or
presenting
actions/vignettes.
This
presupposes
events
are
experienced
leaves
open
questions
about
principles
governing
infant
segmentation.
We
take
a
different,
data-driven
approach
studying
input.
collected
whole-brain
functional
MRI
(fMRI)
data
awake
(and
adults,
comparison)
watching
cartoon
used
hidden
Markov
model
identify
states
brain.
quantified
existence,
timescale,
organization
multiple-event
representations
across
brain
regions.
The
exhibited
known
hierarchical
gradient
timescales,
shorter
early
visual
regions
longer
later
associative
In
contrast,
represented
only
events,
even
regions,
with
no
timescale
hierarchy.
these
partially
overlapped
defined
activity
behavioral
judgments.
These
findings
suggest
that
organized
differently
infants,
timescales
more
stable
neural
patterns,
may
indicate
greater
temporal
integration
reduced
precision
during
dynamic,
naturalistic
perception.
Schematic
prior
knowledge
can
scaffold
the
construction
of
event
memories
during
perception
and
also
provide
structured
cues
to
guide
memory
search
retrieval.
We
measured
activation
story-specific
schematic
representations
using
fMRI
while
participants
were
presented
with
16
stories
then
recalled
each
narratives,
related
these
activations
for
specific
story
details.
predicted
that
schema
in
medial
prefrontal
cortex
(mPFC)
would
be
correlated
successful
recall
In
keeping
this
prediction,
an
anterior
mPFC
region
showed
a
significant
correlation
between
at
encoding
subsequent
behavioral
performance;
however,
was
not
implicated
representation
More
generally,
our
analyses
revealed
largely
distinct
brain
networks
retrieval
which
recall.
These
results
new
insight
into
when
where
support
narrative
memory.
A
fundamental
aspect
of
human
experience
is
that
it
segmented
into
discrete
events.
This
may
be
underpinned
by
transitions
between
distinct
neural
states.
Using
an
innovative
data-driven
state
segmentation
method,
we
investigate
how
states
are
organized
across
the
cortical
hierarchy
and
where
in
cortex
boundaries
perceived
event
overlap.
Our
results
show
a
temporal
hierarchy,
with
short
primary
sensory
regions,
long
lateral
medial
prefrontal
cortex.
State
shared
within
groups
brain
regions
resemble
well-known
functional
networks.
Perceived
overlap
large
parts
particularly
when
those
demarcate
strong
transition
or
regions.
Taken
together,
these
findings
suggest
partially
nested
forms
basis
segmentation.
Cognition
and
attention
arise
from
the
adaptive
coordination
of
neural
systems
in
response
to
external
internal
demands.
The
low-dimensional
latent
subspace
that
underlies
large-scale
dynamics
relationships
these
cognitive
attentional
states,
however,
are
unknown.
We
conducted
functional
magnetic
resonance
imaging
as
human
participants
performed
tasks,
watched
comedy
sitcom
episodes
an
educational
documentary,
rested.
Whole-brain
traversed
a
common
set
states
spanned
canonical
gradients
brain
organization,
with
global
desynchronization
among
networks
modulating
state
transitions.
Neural
were
synchronized
across
people
during
engaging
movie
watching
aligned
narrative
event
structures.
reflected
fluctuations
such
different
indicated
engaged
task
naturalistic
contexts,
whereas
lapses
both
contexts.
Together,
results
demonstrate
traversals
along
organization
reflect
dynamics.
Cell Reports,
Год журнала:
2023,
Номер
42(4), С. 112331 - 112331
Опубликована: Апрель 1, 2023
New
memories
are
not
quarantined
from
each
other
when
first
encoded;
rather,
they
interlinked
with
that
were
encoded
in
temporal
proximity
or
share
semantic
features.
By
selectively
biasing
memory
processing
during
sleep,
here
we
test
whether
context
influences
sleep
consolidation.
Participants
formed
18
idiosyncratic
narratives,
linking
four
objects
together.
Before
also
memorized
an
on-screen
position
for
object.
During
12
object-specific
sounds
unobtrusively
presented,
thereby
cuing
the
corresponding
spatial
and
impacting
recall
as
a
function
of
initial
strength.
As
hypothesized,
find
non-cued
contextually
linked
cued
changed.
Post-cue
electrophysiological
responses
suggest
activity
sigma
band
supports
reinstatement
predicts
context-related
benefits.
Concurrently,
context-specific
patterns
emerge
sleep.
We
conclude
reactivation
individual
evokes
their
context,
consolidation
associated
knowledge.
Psychological Science,
Год журнала:
2023,
Номер
34(3), С. 326 - 344
Опубликована: Янв. 3, 2023
When
recalling
memories,
we
often
scan
information-rich
continuous
episodes,
for
example,
to
find
our
keys.
How
does
brain
access
and
search
through
those
memories?
We
suggest
that
high-level
structure,
marked
by
event
boundaries,
guides
us
this
process:
In
computational
model,
memory
scanning
is
sped
up
skipping
ahead
the
next
boundary
upon
reaching
a
decision
threshold.
adult
Mechanical
Turk
workers
from
United
States,
used
movie
(normed
boundaries;
Study
1,