Proceedings of the Royal Society B Biological Sciences,
Год журнала:
2023,
Номер
290(2001)
Опубликована: Июнь 26, 2023
Ball-rolling
dung
beetles
are
known
to
integrate
multiple
cues
in
order
facilitate
their
straight-line
orientation
behaviour.
Recent
work
has
suggested
that
integrated
according
a
vector
sum,
is,
compass
represented
by
vectors
and
summed
give
combined
estimate.
Further,
cue
weight
(vector
magnitude)
appears
be
set
reliability.
This
is
consistent
with
the
popular
Bayesian
view
of
integration:
reduce
or
minimize
an
agent's
uncertainty
about
external
world.
Integration
believed
occur
at
input
insect
central
complex.
Here,
we
demonstrate
model
head
direction
circuit
complex,
including
plasticity
synapses,
can
act
as
substrate
for
integration
summation.
show
influence
not
necessarily
driven
Finally,
present
beetle
behavioural
experiment
which,
combination
simulation,
strongly
suggests
these
do
We
suggest
alternative
strategy
whereby
weighted
relative
contrast,
which
also
explain
previous
results.
Flexible
behaviors
over
long
timescales
are
thought
to
engage
recurrent
neural
networks
in
deep
brain
regions,
which
experimentally
challenging
study.
In
insects,
circuit
dynamics
a
region
called
the
central
complex
(CX)
enable
directed
locomotion,
sleep,
and
context-
experience-dependent
spatial
navigation.
We
describe
first
complete
electron
microscopy-based
connectome
of
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Июнь 27, 2023
Abstract
The
fruit
fly
Drosophila
melanogaster
combines
surprisingly
sophisticated
behaviour
with
a
highly
tractable
nervous
system.
A
large
part
of
the
fly’s
success
as
model
organism
in
modern
neuroscience
stems
from
concentration
collaboratively
generated
molecular
genetic
and
digital
resources.
As
presented
our
FlyWire
companion
paper
1
,
this
now
includes
first
full
brain
connectome
an
adult
animal.
Here
we
report
systematic
hierarchical
annotation
∼130,000-neuron
including
neuronal
classes,
cell
types
developmental
units
(hemilineages).
This
enables
any
researcher
to
navigate
huge
dataset
find
systems
neurons
interest,
linked
literature
through
Virtual
Fly
Brain
database
2
.
Crucially,
resource
4,552
types.
3,094
are
rigorous
consensus
validations
previously
proposed
“hemibrain”
3
In
addition,
propose
1,458
new
types,
arising
mostly
fact
that
spans
whole
brain,
whereas
hemibrain
derives
subvolume.
Comparison
showed
type
counts
strong
connections
were
largely
stable,
but
connection
weights
variable
within
across
animals.
Further
analysis
defined
simple
heuristics
for
interpretation:
stronger
than
10
unitary
synapses
or
providing
>1%
input
target
conserved.
Some
increased
variability
connectomes:
most
common
mushroom
body,
required
learning
memory,
is
almost
twice
numerous
hemibrain.
We
evidence
functional
homeostasis
adjustments
absolute
amount
excitatory
while
maintaining
excitation-inhibition
ratio.
Finally,
surprisingly,
about
one
third
could
not
yet
be
reliably
identified
connectome.
therefore
suggest
should
robust
inter-individual
variation,
namely
groups
cells
quantitatively
more
similar
different
other
same
brain.
Joint
connectomes
demonstrates
viability
utility
definition.
Our
work
defines
atlas
provides
both
intellectual
framework
open
source
toolchain
brain-scale
comparative
connectomics.
Neuron,
Год журнала:
2024,
Номер
112(15), С. 2581 - 2599.e23
Опубликована: Май 24, 2024
Anchoring
goals
to
spatial
representations
enables
flexible
navigation
but
is
challenging
in
novel
environments
when
both
must
be
acquired
simultaneously.
We
propose
a
framework
for
how
Drosophila
uses
internal
of
head
direction
(HD)
build
goal
upon
selective
thermal
reinforcement.
show
that
flies
use
stochastically
generated
fixations
and
directed
saccades
express
heading
preferences
an
operant
visual
learning
paradigm
HD
neurons
are
required
modify
these
based
on
used
symmetric
setting
expose
flies'
co-evolve
the
reliability
interacting
impacts
behavior.
Finally,
we
describe
rapid
new
headings
may
rest
behavioral
policy
whose
parameters
form
genetically
encoded
circuit
architecture.
Such
evolutionarily
structured
architectures,
which
enable
rapidly
adaptive
behavior
driven
by
representations,
relevant
across
species.
Many
insects
use
patterns
of
polarized
light
in
the
sky
to
orient
and
navigate.
Here,
we
functionally
characterize
neural
circuitry
fruit
fly,
Drosophila
melanogaster
,
that
conveys
signals
from
eye
central
complex,
a
brain
region
essential
for
fly’s
sense
direction.
Neurons
tuned
angle
polarization
ultraviolet
are
found
throughout
anterior
visual
pathway,
connecting
optic
lobes
with
complex
via
tubercle
bulb,
homologous
organization
‘sky
compass’
pathways
described
other
insects.
We
detail
how
consistent,
map-like
tunings
peripheral
system
is
transformed
into
reduced
representation
suited
flexible
processing
brain.
This
study
identifies
computational
motifs
transformation,
enabling
mechanistic
comparisons
multisensory
integration
navigation
brains
Color
and
polarization
provide
complementary
information
about
the
world
are
detected
by
specialized
photoreceptors.
However,
downstream
neural
circuits
that
process
these
distinct
modalities
incompletely
understood
in
any
animal.
Using
electron
microscopy,
we
have
systematically
reconstructed
synaptic
targets
of
photoreceptors
to
detect
color
skylight
Drosophila,
used
light
microscopy
confirm
many
our
findings.
We
identified
known
novel
selective
for
different
wavelengths
or
polarized
light,
followed
their
projections
other
areas
optic
lobes
central
brain.
Our
results
revealed
synapses
along
photoreceptor
axons
between
brain
regions,
new
pathways
lobes,
spatially
segregated
regions.
Strikingly,
polarization-sensitive
dorsal
rim
area
target
fewer
cell
types,
lack
strong
connections
lobula,
a
neuropil
involved
processing.
reconstruction
identifies
shared
wiring
modality-specific
specializations
vision,
provides
comprehensive
view
first
steps
processing
inputs.
Current Opinion in Insect Science,
Год журнала:
2022,
Номер
54, С. 100968 - 100968
Опубликована: Сен. 13, 2022
Methods
to
acquire
and
process
synaptic-resolution
electron-microscopy
datasets
have
progressed
very
rapidly,
allowing
production
annotation
of
larger,
more
complete
connectomes.
More
accurate
neuronal
matching
techniques
are
enriching
cell
type
data
with
gene
expression,
neuron
activity,
behaviour
developmental
information,
providing
ways
test
hypotheses
circuit
function.
In
a
variety
behaviours
such
as
learned
innate
olfaction,
navigation
sexual
behaviour,
connectomics
has
already
revealed
interconnected
modules
hierarchical
structure,
recurrence
integration
sensory
streams.
Comparing
individual
connectomes
determine
which
features
robust
variable
is
one
key
research
area;
new
work
in
comparative
across
development,
experience,
sex
species
will
establish
strong
links
between
connectivity
brain
Abstract
Originally
a
genetic
model
organism,
the
experimental
use
of
Drosophila
melanogaster
has
grown
to
include
quantitative
behavioral
analyses,
sophisticated
perturbations
neuronal
function,
and
detailed
sensory
physiology.
A
highlight
these
developments
can
be
seen
in
context
vision,
where
pioneering
studies
have
uncovered
fundamental
generalizable
principles
processing.
Here
we
begin
with
an
overview
vision-guided
behaviors
common
methods
for
probing
visual
circuits.
We
then
outline
anatomy
physiology
brain
regions
involved
processing,
beginning
at
periphery
ending
descending
motor
control.
Areas
focus
contrast
motion
detection
optic
lobe,
circuits
feature
selectivity,
computations
support
spatial
navigation,
contextual
associative
learning.
Finally,
look
future
fly
neuroscience
discuss
promising
topics
further
study.