Efficiency and reliability in biological neural network architectures
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: March 17, 2024
Abstract
Simplified
models
of
neural
networks
have
demonstrated
the
importance
establishing
a
reasonable
tradeoff
between
memory
capacity
and
fault-tolerance
in
cortical
coding
schemes.
The
intensity
is
mediated
by
level
neuronal
variability.
Indeed,
increased
redundancy
activity
enhances
robustness
code
at
cost
its
efficiency.
We
hypothesized
that
heterogeneous
architecture
biological
provides
substrate
to
regulate
this
tradeoff,
thereby
allowing
different
subpopulations
same
network
optimize
for
objectives.
To
distinguish
subpopulations,
we
developed
metric
based
on
mathematical
theory
simplicial
complexes
captures
complexity
their
connectivity,
contrasting
higher-order
structure
random
control.
confirm
relevance
our
analyzed
several
openly
available
connectomes,
revealing
they
all
exhibited
wider
distributions
across
than
relevant
controls.
Using
biologically
detailed
model
an
electron
microscopic
data
set
connectivity
with
co-registered
functional
data,
showed
low
exhibit
efficient
activity.
Conversely,
high
play
supporting
role
boosting
reliability
as
whole,
softening
robustness-efficiency
tradeoff.
Crucially,
found
both
types
can
do
coexist
within
single
connectome
networks,
due
heterogeneity
connectivity.
Our
work
thus
suggests
avenue
resolving
seemingly
paradoxical
previous
results
assume
homogeneous
Language: Английский
Modeling and Simulation of Neocortical Micro- and Mesocircuitry. Part I: Anatomy
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2022,
Volume and Issue:
unknown
Published: Aug. 15, 2022
Abstract
The
function
of
the
neocortex
is
fundamentally
determined
by
its
repeating
microcircuit
motif,
but
also
rich,
interregional
connectivity.
We
present
a
data-driven
computational
model
anatomy
non-barrel
primary
somatosensory
cortex
juvenile
rat,
integrating
whole-brain
scale
data
while
providing
cellular
and
subcellular
specificity.
consists
4.2
million
morphologically
detailed
neurons,
placed
in
digital
brain
atlas.
They
are
connected
14.2
billion
synapses,
comprising
local,
mid-range
extrinsic
delineated
limits
determining
connectivity
from
neuron
morphology
placement,
finding
that
it
reproduces
targeting
Sst+
requires
additional
specificity
to
reproduce
PV+
VIP+
interneurons.
Globally,
was
characterized
local
clusters
tied
together
through
hub
neurons
layer
5,
demonstrating
how
interegional
complicit,
inseparable
networks.
suitable
for
simulation-based
studies,
211,712
subvolume
made
openly
available
community.
Language: Английский
Assemblies, synapse clustering and network topology interact with plasticity to explain structure-function relationships of the cortical connectome
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Aug. 7, 2023
Synaptic
plasticity
underlies
the
brain's
ability
to
learn
and
adapt.
While
experiments
in
brain
slices
have
revealed
mechanisms
protocols
for
induction
of
between
pairs
neurons,
how
these
synaptic
changes
are
coordinated
biological
neuronal
networks
ensure
emergence
learning
remains
poorly
understood.
Simulation
modeling
emerged
as
important
tools
study
plastic
networks,
but
yet
achieve
a
scale
that
incorporates
realistic
network
structure,
active
dendrites,
multi-synapse
interactions,
key
determinants
plasticity.
To
rise
this
challenge,
we
endowed
an
existing
large-scale
cortical
model,
incorporating
data-constrained
dendritic
processing
multi-synaptic
connections,
with
calcium-based
model
functional
captures
diversity
excitatory
connections
extrapolated
vivo-like
conditions.
This
allowed
us
dendrites
structure
interact
shape
stimulus
representations
at
microcircuit
level.
In
our
exploratory
simulations,
acted
sparsely
specifically,
firing
rates
weight
distributions
remained
stable
without
additional
homeostatic
mechanisms.
At
circuit
level,
found
was
driven
by
co-firing
stimulus-evoked
assemblies,
spatial
clustering
synapses
on
topology
connectivity.
As
result
changes,
became
more
reliable
stimulus-specific
responses.
We
confirmed
testable
predictions
MICrONS
datasets,
openly
available
electron
microscopic
reconstruction
large
volume
tissue.
Our
results
quantify
architecture
higher-order
microcircuits
play
central
role
provide
foundation
elucidating
their
learning.
Language: Английский
Structured stabilization in recurrent neural circuits through inhibitory synaptic plasticity
Dylan Festa,
No information about this author
Claudia Cusseddu,
No information about this author
Julijana Gjorgjieva
No information about this author
et al.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: Oct. 12, 2024
Inhibitory
interneurons
play
a
dual
role
in
recurrently
connected
biological
circuits:
they
regulate
global
neural
activity
to
prevent
runaway
excitation,
and
contribute
complex
computations.
While
the
first
can
be
achieved
through
unstructured
connections
tuned
for
homeostatic
rate
stabilization,
computational
tasks
often
require
structured
excitatory-inhibitory
(E/I)
connectivity.
Here,
we
consider
broad
class
of
pairwise
inhibitory
spike-timing
dependent
plasticity
(iSTDP)
rules,
demonstrating
how
synapses
self-organize
both
stabilize
excitation
generate
functionally
relevant
connectivity
structures
—
process
call
“structured
stabilization”.
We
show
that
E/I
circuit
motifs
large
spiking
recurrent
networks
choice
iSTDP
rule
lead
either
mutually
pairs,
or
lateral
inhibition,
where
an
neuron
connects
excitatory
does
not
directly
connect
back
it.
In
one-dimensional
ring
network,
if
two
populations
follow
these
distinct
forms
iSTDP,
effective
within
population
self-organizes
into
Mexican-hat-like
profile
with
influence
center
away
from
center.
This
leads
emergent
dynamical
properties
such
as
surround
suppression
modular
spontaneous
activity.
Our
theoretical
work
introduces
family
rules
retains
applicability
simplicity
spike-timing-based
plasticity,
while
promoting
structured,
self-organized
stabilization.
These
findings
highlight
rich
interplay
between
structure,
neuronal
dynamics,
offering
framework
understanding
shapes
network
function.
Language: Английский