The
processing
of
visual
information
by
retinal
starburst
amacrine
cells
(SACs)
involves
transforming
excitatory
input
from
bipolar
(BCs)
into
directional
calcium
output.
While
previous
studies
have
suggested
that
an
asymmetry
in
the
kinetic
properties
along
soma-dendritic
axes
postsynaptic
cell
could
enhance
tuning
at
level
individual
branches,
it
remains
unclear
whether
biologically
relevant
presynaptic
kinetics
contribute
to
direction
selectivity
when
stimulation
engages
entire
dendritic
tree.
To
address
this
question,
we
built
multicompartmental
models
bipolar–SAC
circuit
and
trained
them
boost
tuning.
We
report
despite
significant
crosstalk
dissimilar
preferences
dendrites
occur
during
whole-cell
stimulation,
rules
guide
BC
leading
optimal
are
similar
single-dendrite
condition.
correlate
model
predictions
empirical
findings,
utilized
two-photon
glutamate
imaging
study
dynamics
release
onto
ON-
OFF-starburst
murine
retina.
reveal
diverse
response
motion
both
populations;
algorithms
on
experimental
data
differences
temporal
likely
correspond
heterogeneous
receptive
field
(RF)
among
different
types,
including
spatial
extent
center
surround
components.
In
addition,
demonstrate
architecture
composed
units
with
experimentally
recorded
drive
but
not
levels
replicate
suggesting
other
DS
mechanisms
required
explain
SAC
function.
Our
provides
new
insights
complex
underlying
highlights
potential
contribution
computation
cells.
2022 IEEE/CVF Conference on Computer Vision and Pattern Recognition Workshops (CVPRW),
Год журнала:
2023,
Номер
unknown, С. 3054 - 3063
Опубликована: Июнь 1, 2023
Detecting
tiny/small
objects
(e.g.,
drone
targets)
in
videos
is
highly
desired
many
realistic
scenarios.
Nevertheless,
current
object
detection
algorithms
can
hardly
recognize
tiny
targets
against
extremely
complex
backgrounds.
To
address
this
problem,
we
propose
a
motion-guided
video
tiny-object
method
(MG-VTOD),
which
the
spatial-temporal
motion
strength
maps
play
an
important
role
searching
and
locating.
Inspired
by
biological
retinal
structure,
compute
using
sequential
frame
cube
that
has
been
aligned
registered.
Subsequently,
are
employed
to
enhance
potential
areas
of
moving
targets,
thereby
facilitating
target
procedure.
Experimental
results
obtained
on
Anti-UAV-2021
dataset
validate
proposed
MG-VTOD
significantly
outperforms
competing
methods.
Changes
in
synaptic
strength
across
timescales
are
integral
to
algorithmic
operations
of
neural
circuits.
However,
pinpointing
loci
that
undergo
plasticity
intact
brain
circuits
and
delineating
contributions
circuit
function
remain
challenging.
The
whole-mount
retina
preparation
provides
an
accessible
platform
for
measuring
at
specific
synapses
while
monitoring
circuit-level
behaviors
during
visual
processing
ex
vivo.
In
this
review,
we
discuss
insights
gained
from
studies
into
the
versatile
roles
short-term
context-dependent
functions.
Plasticity
single
synapse
level
greatly
expands
algorithms
common
microcircuit
motifs
contributes
diverse
such
as
gain
modulation,
selective
gating,
stimulus-dependent
excitatory/inhibitory
balance.
Examples
retinal
circuitry
offer
unequivocal
support
increases
computational
capacity
hardwired
circuitry.
Frontiers in Neuroanatomy,
Год журнала:
2022,
Номер
15
Опубликована: Янв. 13, 2022
In
the
retina,
evolutionary
changes
can
be
traced
in
topography
of
photoreceptors.
The
shape
visual
streak
depends
on
height
animal
and
its
habitat,
namely,
woods,
prairies,
or
mountains.
Also,
distribution
distinct
wavelength-sensitive
cones
is
unique
to
each
animal.
For
example,
UV
green
reside
ventral
dorsal
regions
mouse
respectively,
whereas
rat
retina
these
are
homogeneously
distributed.
contrast
with
abundant
investigation
photoreceptors
third-order
neurons,
bipolar
cells
has
not
been
well
understood.
We
utilized
two
enhanced
fluorescent
protein
(EGFP)
lines,
Lhx4-EGFP
(Lhx4)
6030405A18Rik-EGFP
(Rik),
examine
topographic
distributions
retina.
First,
we
characterized
their
GFP-expressing
using
type-specific
markers.
found
that
GFP
was
expressed
by
type
2,
3a,
6
Rik
mice
3b,
4,
5
Lhx4
mice.
All
types
achromatic.
Then,
examined
four
cardinal
directions
three
different
eccentricities
retinal
tissue.
mice,
were
more
highly
observed
nasal
region
than
those
temporal
number
along
ventral-dorsal
axis.
contrast,
occurred
at
a
higher
density
However,
no
difference
nasal-temporal
Furthermore,
which
contributed
asymmetric
3a
region,
denser
region.
asymmetricity
shaped
uneven
conclusion,
subset
achromatic
asymmetrically
distributed
suggesting
roles
processing.
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Апрель 17, 2023
SUMMARY
Visual
processing
depends
on
sensitive
and
balanced
synaptic
neurotransmission.
Extracellular
matrix
proteins
in
the
environment
of
cells
are
key
modulators
synaptogenesis
plasticity.
In
present
study,
we
provide
evidence
that
combined
loss
four
extracellular
components
brevican,
neurocan,
tenascin-C
tenascin-R
quadruple
knockout
mice
leads
to
severe
retinal
dysfunction
diminished
visual
motion
vivo
.
Remarkably,
impaired
was
accompanied
by
a
developmental
cholinergic
direction-selective
starburst
amacrine
cells.
Additionally,
noted
imbalance
inhibitory
excitatory
signaling
retina.
Collectively,
study
offers
novel
insights
into
functional
importance
for
function,
integrity.
Graphical
Abstract
brief
their
Reinhard
et
al.
show
dysfunction,
processing,
Highlights
Combined
molecules
causes
Impaired
quadruple,
Loss
retina
The
matrisome
influences
balance
Frontiers in Ophthalmology,
Год журнала:
2023,
Номер
3
Опубликована: Июль 24, 2023
The
role
of
acetylcholine
(ACh)
in
visual
processing
the
mammalian
retina
has
been
focus
research
for
many
decades.
Pioneering
work
on
localization
ACh
discovered
that
neurotransmitter
is
synthesized
and
stored
a
distinct
subpopulation
amacrine
(starburst)
cells.
It
shown
release
regulated
to
low
resting
"tonic"
level,
much
like
what
observed
at
neuromuscular
junction
(NMJ).
If
there
were
dysfunction
tonic
ACh,
might
post-synaptic
changes
render
targets
[i.e.,
retinal
ganglion
cells
(RGCs)]
vulnerable
disease?
During
my
time
Pharmacia
&
Upjohn
(PNU),
selective
nicotinic
receptor
(nAChR)
agonists
(e.g.,
PNU-282987)
developed
as
possible
therapy
central
nervous
system
(CNS)
diseases.
As
RGCs
are
main
neurodegeneration
glaucoma,
could
activation
this
target
provide
neuroprotection?
In
response
question,
experiments
identify
alpha7
nAChRs
(i.e.,
ID
studies)
followed
by
"proof-of-concept"
conducted.
Target
studies
included
binding
with
homogenates,
[
The
processing
of
visual
information
by
retinal
starburst
amacrine
cells
(SACs)
involves
transforming
excitatory
input
from
bipolar
(BCs)
into
directional
calcium
output.
While
previous
studies
have
suggested
that
an
asymmetry
in
the
kinetic
properties
along
soma-dendritic
axes
postsynaptic
cell
could
enhance
tuning
at
level
individual
branches,
it
remains
unclear
whether
biologically
relevant
presynaptic
kinetics
contribute
to
direction
selectivity
when
stimulation
engages
entire
dendritic
tree.
To
address
this
question,
we
built
multicompartmental
models
bipolar–SAC
circuit
and
trained
them
boost
tuning.
We
report
despite
significant
crosstalk
dissimilar
preferences
dendrites
occur
during
whole-cell
stimulation,
rules
guide
BC
leading
optimal
are
similar
single-dendrite
condition.
correlate
model
predictions
empirical
findings,
utilized
two-photon
glutamate
imaging
study
dynamics
release
onto
ON-
OFF-starburst
murine
retina.
reveal
diverse
response
motion
both
populations;
algorithms
on
experimental
data
differences
temporal
likely
correspond
heterogeneous
receptive
field
(RF)
among
different
types,
including
spatial
extent
center
surround
components.
In
addition,
demonstrate
architecture
composed
units
with
experimentally
recorded
drive
but
not
levels
replicate
suggesting
other
DS
mechanisms
required
explain
SAC
function.
Our
provides
new
insights
complex
underlying
highlights
potential
contribution
computation
cells.
The
processing
of
visual
information
by
retinal
starburst
amacrine
cells
(SACs)
involves
transforming
excitatory
input
from
bipolar
(BCs)
into
directional
calcium
output.
While
previous
studies
have
suggested
that
an
asymmetry
in
the
kinetic
properties
BCs
along
soma-dendritic
axes
postsynaptic
cell
could
enhance
tuning
at
level
individual
branches,
it
remains
unclear
whether
biologically
relevant
presynaptic
kinetics
contribute
to
direction
selectivity
(DS)
when
stimulation
engages
entire
dendritic
tree.
To
address
this
question,
we
built
multicompartmental
models
bipolar-SAC
circuit
and
trained
them
boost
tuning.
We
report
despite
significant
crosstalk
dissimilar
preferences
dendrites
occur
during
whole-cell
stimulation,
rules
guide
BC
leading
optimal
DS
are
similar
single-dendrite
condition.
correlate
model
predictions
empirical
findings,
utilized
two-photon
glutamate
imaging
study
dynamics
release
onto
ON-
OFF-starburst
murine
retina.
reveal
diverse
response
motion
both
populations;
algorithms
on
experimental
data
differences
temporal
likely
correspond
heterogeneous
receptive
field
among
different
types,
including
spatial
extent
center
surround
components.
In
addition,
demonstrate
architecture
composed
units
with
experimentally
recorded
drive
but
not
levels
replicate
suggesting
other
mechanisms
required
explain
SAC
function.
Our
provides
new
insights
complex
underlying
highlights
potential
contribution
computation
SACs.
PLoS Biology,
Год журнала:
2023,
Номер
21(9), С. e3002301 - e3002301
Опубликована: Сен. 18, 2023
Motion
is
an
important
aspect
of
visual
information.
The
directions
motion
are
encoded
in
the
retina
by
direction-selective
ganglion
cells
(DSGCs).
ON-OFF
DSGCs
and
ON
co-stratify
with
starburst
amacrine
(SACs)
inner
plexiform
layer
depend
on
SACs
for
their
direction
selectivity.
J-type
retinal
(J-RGCs),
a
type
OFF
mouse
retina,
other
hand,
do
not
SACs,
how
selectivity
J-RGCs
emerges
has
been
understood.
Here,
we
report
that
both
excitatory
inhibitory
synaptic
inputs
to
(DS),
playing
more
role
DS
come
from
functional
connections
between
spatially
asymmetric.
Thus,
form
functionally
contacts
even
though
dendritic
arbors
show
little
overlap.
These
findings
underscore
need
look
beyond
neurons’
stratification
patterns
circuit
studies.
Our
results
also
highlight
critical
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Ноя. 15, 2023
Abstract
Spontaneous
retinal
waves
are
a
critical
driving
force
for
the
self-organization
of
mouse
visual
system
prior
to
eye-opening.
Classically
characterized
as
taking
place
in
three
distinct
stages
defined
by
their
primary
excitatory
drive,
Stage
II
during
first
postnatal
week
propagated
through
volume
transmission
acetylcholine
while
III
second
depend
on
glutamatergic
from
bipolar
cells.
However,
both
late
and
early
share
defining
propagation
bias
toward
temporal-to-nasal
direction
despite
developmental
changes
underlying
cholinergic
networks.
Here,
we
leverage
genetic
pharmacological
manipulations
investigate
relationship
between
neurotransmission
transition
vivo.
We
find
that
network
continues
play
vital
role
after
mode
glutamate.
In
absence
waves,
compensatory
activity
persists
but
lacks
typically
observed
waves.
gap
junction-mediated
associated
with
I
throughout
window
which
usually
emerge
spatiotemporal
profile
normal
including
bias.
Finally,
show
signaling
β2
subunit-containing
nicotinic
receptors,
essential
wave
propagation,
is
also
directionality.
