bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: June 23, 2024
Abstract
Olfactory-driven
behaviors
are
essential
for
animal
survival,
but
mechanisms
decoding
olfactory
inputs
remain
poorly
understood.
We
have
used
whole-network
Ca
++
imaging
to
study
coding
in
Caenorhabditis
elegans.
show
that
the
odorant
1-octanol
is
encoded
combinatorially
periphery
as
both
an
attractant
and
a
repellant.
These
integrated
centrally,
their
relative
strengths
determine
sensitivity
valence
of
behavioral
response
through
modulation
locomotory
reversals
speed.
The
balance
these
pathways
also
dictates
activity
command
interneurons,
which
control
reversals.
This
serves
regulatory
node
modulation,
allowing
C.
elegans
weigh
opportunities
hazards
its
environment
when
formulating
responses.
Thus,
can
be
simultaneously
opposite
valence,
focusing
attention
on
integration
determining
perception,
response,
plasticity.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: April 27, 2023
Abstract
The
human
brain
is
a
highly
connected
network
with
complex
patterns
of
correlated
and
anticorrelated
activity.
Analyzing
functional
connectivity
matrices
derived
from
neuroimaging
data
can
provide
insights
into
the
organization
networks
their
association
cognitive
processes
or
disorders.
Common
approaches,
such
as
thresholding
binarization,
often
disregard
negative
connections,
which
may
result
in
loss
critical
information.
This
study
introduces
an
adaptive
signed
random
walk
(ASRW)
model
for
analyzing
correlation-
based
that
incorporates
both
positive
connections.
calculates
transition
probabilities
between
regions
function
activities
connection
strengths,
dynamically
updating
on
differences
node
activity
strengths
at
each
time
step.
Results
show
classical
approach,
only
considers
absolute
value
underestimates
mean
first
passage
(MFPT)
compared
to
proposed
ASRW
model.
Our
captures
wide
range
interactions
dynamics
within
network,
providing
more
comprehensive
understanding
its
structure
function.
suggests
considering
has
potential
offer
valuable
interregional
coordination
underlying
various
behaviors.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: March 18, 2024
Background:
Functional
connectivity
in
the
context
of
functional
magnetic
resonance
imaging
is
typically
quantified
by
Pearson
or
partial
correlation
between
regional
time
series
blood
oxygenation
level
dependent
signal.
However,
a
recent
interdisciplinary
methodological
work
proposes
more
than
230
different
metrics
to
measure
similarity
types
series.
Objective:
Hence,
we
systematically
evaluated
how
results
typical
research
approaches
neuroimaging
vary
depending
on
metric
choice.
We
further
explored
which
most
accurately
detect
neural
decline
induced
age
and
malignant
brain
tumors,
aiming
initiate
debate
best
assessing
research.
Methods:
addressed
both
questions
using
four
independent
datasets,
comprising
multimodal
data
from
total
1187
individuals.
analyzed
resting-state
sequences
calculate
20
representative
distinct
mathematical
domains.
used
T1-
T2-weighted
images
compute
volumes,
diffusion-weighted
build
structural
connectomes,
pseudo-continuous
arterial
spin
labeling
perfusion.
Results:
First,
our
demonstrate
that
differ
fundamentally
Second,
show
correlational
distance
are
appropriate
cover
age.
In
this
context,
performs
worse
other
metrics.
Third,
findings
suggest
FC
choice
depends
utilized
scanning
parameters,
regions
interest,
individual
investigated.
Lastly,
beyond
major
objective
study,
provide
evidence
favor
perfusion
measured
via
as
robust
entity
mirroring
age-related
cognitive
decline.
Conclusion:
Our
empirical
evaluation
supports
theoretical
framework.
Future
studies
need
comprehensively
define
study-specific
property
assess
property,
confounding
may
bias
conclusions.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: June 23, 2024
Abstract
Olfactory-driven
behaviors
are
essential
for
animal
survival,
but
mechanisms
decoding
olfactory
inputs
remain
poorly
understood.
We
have
used
whole-network
Ca
++
imaging
to
study
coding
in
Caenorhabditis
elegans.
show
that
the
odorant
1-octanol
is
encoded
combinatorially
periphery
as
both
an
attractant
and
a
repellant.
These
integrated
centrally,
their
relative
strengths
determine
sensitivity
valence
of
behavioral
response
through
modulation
locomotory
reversals
speed.
The
balance
these
pathways
also
dictates
activity
command
interneurons,
which
control
reversals.
This
serves
regulatory
node
modulation,
allowing
C.
elegans
weigh
opportunities
hazards
its
environment
when
formulating
responses.
Thus,
can
be
simultaneously
opposite
valence,
focusing
attention
on
integration
determining
perception,
response,
plasticity.