bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2022,
Volume and Issue:
unknown
Published: Dec. 23, 2022
Abstract
Successful
explicit
memory
encoding
is
associated
with
inferior
temporal
activations
and
medial
parietal
deactivations,
which
are
attenuated
in
aging.
Here
we
used
Dynamic
Causal
Modeling
(DCM)
of
functional
magnetic
resonance
imaging
data
to
elucidate
effective
connectivity
patterns
between
hippocampus,
parahippocampal
place
area
(PPA)
precuneus
during
novel
visual
scenes.
In
117
young
adults,
DCM
revealed
pronounced
activating
input
from
the
PPA
hippocampus
inhibitory
novelty
processing,
both
being
enhanced
successful
encoding.
This
pattern
could
be
replicated
two
cohorts
(N
=
141
148)
older
adults.
cohorts,
adults
selectively
exhibited
PPA-precuneus
connectivity,
correlated
negatively
performance.
Our
results
provide
insight
into
network
dynamics
underlying
suggest
that
age-related
differences
memory-related
activity
are,
at
least
partly,
attributable
altered
temporo-parietal
neocortical
connectivity.
Human Brain Mapping,
Journal Year:
2023,
Volume and Issue:
44(9), P. 3586 - 3609
Published: April 13, 2023
Abstract
The
default
mode
network
(DMN)
typically
exhibits
deactivations
during
demanding
tasks
compared
to
periods
of
relative
rest.
In
functional
magnetic
resonance
imaging
(fMRI)
studies
episodic
memory
encoding,
increased
activity
in
DMN
regions
even
predicts
later
forgetting
young
healthy
adults.
This
association
is
attenuated
older
adults
and,
some
instances,
remembering
rather
than
forgetting.
It
yet
unclear
whether
this
phenomenon
due
a
compensatory
mechanism,
such
as
self‐referential
or
schema‐dependent
it
reflects
overall
reduced
modulation
age.
We
approached
question
by
systematically
comparing
successful
encoding
and
tonic,
task‐independent,
at
rest
sample
106
(18–35
years)
111
(60–80
participants.
Using
voxel‐wise
multimodal
analyses,
we
assessed
the
age‐dependent
relationship
between
resting‐state
amplitude
(mean
percent
fluctuation,
mPerAF)
fMRI
signals
related
well
their
age‐related
hippocampal
volume
loss,
while
controlling
for
regional
grey
matter
volume.
Older
showed
lower
amplitudes
task‐related
deactivations.
However,
negative
mPerAF
subsequent
effect
within
precuneus
was
observed
only
young,
but
not
Hippocampal
volumes
no
with
mPerAF.
Lastly,
higher
tend
show
performance,
pointing
towards
importance
maintained
ability
modulate
old
Brain Communications,
Journal Year:
2024,
Volume and Issue:
6(6)
Published: Jan. 1, 2024
Neuronal
dysfunction
in
specific
brain
regions
or
across
distributed
networks
is
a
known
feature
of
Alzheimer's
disease.
An
often
reported
finding
the
early
stage
disease
presence
increased
functional
MRI
(fMRI)
blood
oxygenation
level-dependent
signal
under
task
conditions
relative
to
cognitively
normal
controls,
phenomenon
as
'hyperactivation'.
However,
research
past
decades
yielded
complex,
sometimes
conflicting
results.
The
magnitude
and
topology
fMRI
hyperactivation
patterns
have
been
found
vary
preclinical
clinical
spectrum
disease,
including
concomitant
'hypoactivation'
some
cases.
These
incongruences
are
likely
due
range
factors,
at
which
cohort
examined,
areas
studied
paradigm
utilized
evoke
these
abnormalities.
Additionally,
perennial
question
pertains
nature
context
Some
propose
it
reflects
compensatory
mechanisms
sustain
cognitive
performance,
while
others
suggest
linked
pathological
disruption
highly
regulated
homeostatic
cycle
that
contributes
to,
even
drives,
progression.
Providing
coherent
narrative
for
empirical
conceptual
discrepancies
paramount
develop
models,
understand
synergy
between
cascade
tailor
effective
interventions.
We
first
provide
comprehensive
overview
changes
spanning
course
from
ageing
then
highlight
evidence
supporting
close
relationship
Brain,
Journal Year:
2024,
Volume and Issue:
147(11), P. 3789 - 3803
Published: May 14, 2024
Abstract
Single-value
scores
reflecting
the
deviation
from
(FADE
score)
or
similarity
with
(SAME
prototypical
novelty-related
and
memory-related
functional
MRI
activation
patterns
in
young
adults
have
been
proposed
as
imaging
biomarkers
of
healthy
neurocognitive
ageing.
Here,
we
tested
utility
these
potential
diagnostic
prognostic
markers
Alzheimer’s
disease
(AD)
risk
states
like
mild
cognitive
impairment
(MCI)
subjective
decline
(SCD).
To
this
end,
analysed
subsequent
memory
data
individuals
SCD,
MCI
AD
dementia
well
controls
first-degree
relatives
patients
(AD-rel)
who
participated
multi-centre
DELCODE
study
(n
=
468).
Based
on
individual
participants’
whole-brain
novelty
responses,
calculated
FADE
SAME
assessed
their
association
stage,
neuropsychological
test
scores,
CSF
amyloid
positivity
APOE
genotype.
Memory-based
showed
a
considerably
larger
reference
sample
groups
compared
to
controls,
SCD
AD-rel.
In
addition,
novelty-based
significantly
differed
between
groups.
Across
entire
sample,
single-value
correlated
performance.
The
score
further
Aβ-positive
Aβ-negative
AD-rel,
ApoE
ɛ4
carriers
non-carriers
Hence,
are
associated
both
performance
factors
for
AD.
Their
warrants
exploration,
particularly
patients.
Nature Communications,
Journal Year:
2024,
Volume and Issue:
15(1)
Published: Nov. 13, 2024
The
cognitive
reserve
(CR)
hypothesis
posits
that
individuals
can
differ
in
how
their
brain
function
is
disrupted
by
pathology
associated
with
aging
and
neurodegeneration.
Here,
we
test
this
the
continuum
from
cognitively
normal
to
at-risk
stages
for
Alzheimer's
Disease
(AD)
AD
dementia
using
longitudinal
data
490
participants
of
DELCODE
multicentric
observational
study.
Brain
measured
task
fMRI
visual
memory
encoding.
Using
a
multivariate
moderation
analysis,
identify
CR-related
activity
pattern
underlying
successful
encoding
moderates
detrimental
effect
pathological
load
on
performance.
CR
mainly
represented
more
pronounced
expression
task-active
network
encompassing
deactivation
default
mode
(DMN)
activation
inferior
temporal
regions
including
fusiform
gyrus.
We
devise
personalized
fMRI-based
scores
moderate
impact
performance
are
positively
years
education.
Furthermore,
higher
attenuate
decline
over
time.
Our
findings
primarily
provide
evidence
maintenance
core
circuits
DMN
as
neural
basis
CR.
Individual
levels
these
areas
during
have
prognostic
value
future
decline.
iScience,
Journal Year:
2023,
Volume and Issue:
26(10), P. 107765 - 107765
Published: Aug. 29, 2023
Successful
explicit
memory
encoding
is
associated
with
inferior
temporal
activations
and
medial
parietal
deactivations,
which
are
attenuated
in
aging.
Here
we
used
dynamic
causal
modeling
(DCM)
of
functional
magnetic
resonance
imaging
data
to
elucidate
effective
connectivity
patterns
between
hippocampus,
parahippocampal
place
area
(PPA),
precuneus
during
novel
visual
scenes.
In
117
young
adults,
DCM
revealed
pronounced
activating
input
from
the
PPA
hippocampus
inhibitory
novelty
processing,
both
being
enhanced
successful
encoding.
This
pattern
could
be
replicated
two
cohorts
(N
=
141
148)
older
adults.
cohorts,
adults
selectively
exhibited
PPA-precuneus
connectivity,
correlated
negatively
performance.
Our
results
provide
insight
into
network
dynamics
underlying
suggest
that
age-related
differences
memory-related
activity
are,
at
least
partly,
attributable
altered
temporo-parietal
neocortical
connectivity.
Frontiers in Neuroscience,
Journal Year:
2025,
Volume and Issue:
18
Published: Jan. 23, 2025
Introduction
Researchers
have
shown
that
music-evoked
autobiographical
memories
(MEAMs)
can
stimulate
long-term
memory
mechanisms
while
requiring
little
retrieval
effort
and
may
therefore
be
used
in
promising
non-pharmacological
interventions
to
mitigate
deficits.
Despite
an
increasing
number
of
studies
on
MEAMs,
few
researchers
explored
how
MEAMs
are
bound
the
brain.
Methods
In
current
study
activation
indexed
by
fractional
amplitude
low
frequency
fluctuations
(fALFF)
during
familiar
unfamiliar
MEAM
was
compared
a
sample
24
healthy
older
adults.
Additionally,
we
aimed
investigate
impact
age-related
gray
matter
volume
(GMV)
reduction
key
regions
associated
with
MEAM-related
activation.
addition
T1
structural
scan,
neuroimaging
data
were
collected
participants
listened
music
(MEAM
retrieval)
versus
music.
Results
When
listening
music,
greater
fALFF
patterns
observed
right
parahippocampal
gyrus,
controlling
for
age
GMV.
The
findings
(MEAM)
condition
implications
cognitive
aging
as
persons
experiencing
decline
particularly
susceptible
volumetric
cortex.
Post-hoc
analyses
explore
correlations
between
brain
activity
content
performed
using
text
analysis
program
Linguistic
Inquiry
Word
Count.
Discussion
Our
suggest
cortex
is
evident
normative
However,
it
yet
determined
whether
such
states
attainable
adult
populations
diagnosed
mild
impairment
and/or
prodromal
Alzheimer’s
disease.
PLoS ONE,
Journal Year:
2024,
Volume and Issue:
19(5), P. e0299939 - e0299939
Published: May 2, 2024
Participation
in
multimodal
leisure
activities,
such
as
playing
a
musical
instrument,
may
be
protective
against
brain
aging
and
dementia
older
adults
(OA).
Potential
neuroprotective
correlates
underlying
activity
remain
unclear.
eNeuro,
Journal Year:
2022,
Volume and Issue:
9(6), P. ENEURO.0212 - 22.2022
Published: Nov. 1, 2022
Abstract
Human
cognitive
abilities
decline
with
increasing
chronological
age,
decreased
explicit
memory
performance
being
most
strongly
affected.
However,
some
older
adults
show
“successful
aging,”
that
is,
relatively
preserved
ability
in
old
age.
One
explanation
for
this
could
be
higher
brain-structural
integrity
these
individuals.
Alternatively,
the
brain
might
recruit
existing
resources
more
efficiently
or
employ
compensatory
strategies.
Here,
we
approached
question
by
testing
multiple
candidate
variables
from
structural
and
functional
neuroimaging
their
to
predict
age
performance,
respectively.
Prediction
was
performed
using
support
vector
machine
(SVM)
classification
regression
across
within
two
samples
of
young
(
N
=
106)
153)
adults.
The
were
(1)
behavioral
response
frequencies
an
episodic
test;
(2)
recently
described
magnetic
resonance
imaging
(fMRI)
scores
reflecting
preservation
networks;
(3)
whole-brain
fMRI
contrasts
novelty
processing
subsequent
memory;
(4)
resting-state
maps
quantifying
voxel-wise
signal
fluctuation;
(5)
gray
matter
volume
estimated
MRIs.
While
group
reliably
decoded
all
variables,
subjects
best
predicted
volume.
In
contrast,
task-based
particularly
single-value
scores,
whereas
has
no
predictive
power
respect
healthy
Our
results
suggest
superior
is
better
explained
efficient
recruitment
networks
rather
than
structure.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: July 22, 2024
Abstract
The
precuneus
is
an
early
site
of
amyloid-beta
(Aβ)
accumulation.
Previous
cross-sectional
studies
reported
increased
fMRI
activity
in
older
adults
with
mild
cognitive
deficits
or
elevated
Aβ.
However,
longitudinal
Alzheimer’s
disease
(AD)
risk
stages
are
lacking
and
the
interaction
Apolipoprotein-E
(
APOE
)
genotype
unclear.
In
PREVENT-AD
cohort,
we
assessed
how
during
successful
memory
retrieval
at
baseline
over
time
relates
to
future
Aβ
tau
burden
change
performance.
We
further
studied
moderation
by
APOE4
genotype.
included
165
(age:
62.8±4.4
years;
113
female;
66
carriers)
who
were
cognitively
normal
had
a
family
history
AD.
All
participants
performed
task-fMRI
underwent
18
F-flortaucipir-PET
F-NAV4694-Aβ-PET
on
average
5
years
later.
found
that
higher
greater
associated
subsequent
4
carriers
but
not
non-carriers.
There
no
effects
burden.
Finally,
non-carriers
low
exhibited
better
performance
independent
test
compared
high
carriers.
Our
findings
suggest
task-related
results
indicate
absence
hyperactivation
allele
related
best
outcome
for
Significance
Statement
brain
region
involved
episodic
function
Alterations
occur
ageing
as
well
pathology
even
symptoms;
however,
their
course
implications
understood.
demonstrate
its
after
Apolipoprotein-E4
APOE4)
Lower
activation
was
provide
novel
evidence
posterior
midline
regions
linked
AD
dependence
