bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Nov. 1, 2023
Abstract
In
the
absence
of
adaptation,
average
firing
rate
neurons
would
rise
or
drop
when
changes
in
environment
make
their
preferred
stimuli
more
less
prevalent.
However,
by
adjusting
responsiveness
neurons,
adaptation
can
yield
homeostasis
and
stabilise
rates
at
fixed
levels,
despite
stimulus
statistics.
sensory
cortex,
is
typically
also
specific,
that
reduce
to
over-represented
stimuli,
but
maintain
even
increase
far
from
ones.
Here,
we
present
a
normative
explanation
grounded
efficient
coding
principle,
showing
this
yields
an
optimal
trade-off
between
fidelity
metabolic
cost
neural
firing.
Unlike
previous
theories,
formulate
problem
computation-agnostic
manner,
enabling
our
framework
apply
periphery.
We
then
general
Distributed
Distributional
Codes,
specific
computational
theory
representations
serving
Bayesian
inference.
demonstrate
how
homeostatic
coding,
combined
with
such
representations,
provides
for
stimulus-specific
widely
observed
across
brain,
scheme
be
accomplished
divisive
normalisation
adaptive
weights.
Further,
develop
model
within
framework,
fitting
it
previously
published
experimental
data,
quantitatively
account
measures
adaption
primary
visual
cortex.
Proceedings of the National Academy of Sciences,
Journal Year:
2024,
Volume and Issue:
121(45)
Published: Nov. 1, 2024
The
relationship
between
neurons'
input
and
spiking
output
is
central
to
brain
computation.
Studies
in
vitro
anesthetized
animals
suggest
that
nonlinearities
emerge
cells'
input-output
(IO;
activation)
functions
as
network
activity
increases,
yet
how
neurons
transform
inputs
vivo
has
been
unclear.
Here,
we
characterize
cortical
principal
activation
awake
mice
using
two-photon
optogenetics.
We
deliver
fixed
at
the
soma
while
varies
with
sensory
stimuli.
find
responses
optogenetic
are
nearly
unchanged
excited,
reflecting
a
linear
response
regime
above
resting
point.
In
contrast,
dramatically
attenuated
by
suppression.
This
attenuation
powerful
means
filter
arriving
suppressed
cells,
privileging
other
excited
neurons.
These
results
have
two
major
implications.
First,
somatic
neural
accord
used
recent
machine
learning
systems.
Second,
IO
can
inputs-not
only
do
stimuli
change
outputs,
but
these
changes
also
affect
input,
attenuating
some
leaving
others
unchanged.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 9, 2025
The
process
by
which
neocortical
neurons
and
circuits
amplify
their
response
to
an
unexpected
change
in
stimulus,
often
referred
as
deviance
detection
(DD),
has
long
been
thought
be
the
product
of
specialized
cell
types
and/or
routing
between
mesoscopic
brain
areas.
Here,
we
explore
a
different
theory,
whereby
DD
emerges
from
local
network-level
interactions
within
column.
We
propose
that
deviance-driven
neural
dynamics
can
emerge
through
ensembles
have
fundamental
inhibitory
motif:
competitive
inhibition
reciprocally
connected
under
modulation
feed-forward
selective
(dis)inhibition.
Using
this
framework,
were
able
simulate
variety
phenomena
pertaining
experimentally
observed
shifts
tuning
across
neurons,
time,
stimulus
history.
Anchoring
our
approach
phenomena,
used
computation
modeling
two
networks
vastly
levels
biophysical
detail
test
hypotheses
on
emergent
robustness
underlying
connectivity
parameters.
With
number
corollary
predictions
tested
future
vivo
studies,
show
ensemble
priming
via
(dis)inhibition
acts
mechanism
for
sensory
context
storage
does
not
require
input
other
areas-a
novel
theoretical
paradigm
resolves
previously
confounding
aspects
encoding
predictive
processing
neocortex.
PRX Life,
Journal Year:
2025,
Volume and Issue:
3(2)
Published: May 20, 2025
Networks
of
excitatory
and
inhibitory
(EI)
neurons
form
a
canonical
circuit
in
the
brain.
Seminal
theoretical
results
on
dynamics
such
networks
are
based
assumption
that
synaptic
strengths
depend
type
they
connect,
but
otherwise
statistically
independent.
Recent
physiology
datasets,
however,
highlight
prominence
specific
connectivity
patterns
go
well
beyond
what
is
expected
from
independent
connections.
While
decades
influential
research
have
demonstrated
strong
role
basic
EI
cell
structure,
extent
to
which
additional
features
influence
remains
be
fully
determined.
Here
we
examine
effects
pairwise
motifs
linear
excitatory-inhibitory
using
an
analytical
framework
approximates
terms
low-rank
structures.
This
approximation
mathematical
derivation
dominant
eigenvalues
matrix,
it
predicts
impact
responses
external
inputs
their
interactions
with
cell-type
structure.
Our
reveal
particular
pattern
connectivity,
namely
chain
motifs,
much
stronger
eigenmodes
than
other
motifs.
In
particular,
over-representation
induces
positive
eigenvalue
inhibition-dominated
networks,
generates
potential
instability
requires
revisiting
classical
excitation-inhibition
balance
criteria.
Examining
inputs,
show
can
own
induce
paradoxical
responses,
where
increased
input
leads
decrease
activity
due
recurrent
feedback.
These
findings
direct
implications
for
interpretation
experiments
optogenetic
perturbations
measured
used
infer
dynamical
regime
cortical
circuits.
Published
by
American
Physical
Society
2025
In
the
absence
of
adaptation,
average
firing
rate
neurons
would
rise
or
drop
when
changes
in
environment
make
their
preferred
stimuli
more
less
prevalent.
However,
by
adjusting
responsiveness
neurons,
adaptation
can
yield
homeostasis
and
stabilise
rates
at
fixed
levels,
despite
stimulus
statistics.
sensory
cortex,
is
typically
also
specific,
that
reduce
to
over-represented
stimuli,
but
maintain
even
increase
far
from
ones.
Here,
we
present
a
normative
explanation
grounded
efficient
coding
principle,
showing
this
yields
an
optimal
trade-off
between
fidelity
metabolic
cost
neural
firing.
Unlike
previous
theories,
formulate
problem
computation-agnostic
manner,
enabling
our
framework
apply
periphery.
We
then
general
Distributed
Distributional
Codes,
specific
computational
theory
representations
serving
Bayesian
inference.
demonstrate
how
homeostatic
coding,
combined
with
such
representations,
provides
for
stimulus-specific
widely
observed
across
brain,
scheme
be
accomplished
divisive
normalisation
adaptive
weights.
Further,
develop
model
within
framework,
fitting
it
previously
published
experimental
data,
quantitatively
account
measures
adaption
primary
visual
cortex.
In
the
absence
of
adaptation,
average
firing
rate
neurons
would
rise
or
drop
when
changes
in
environment
make
their
preferred
stimuli
more
less
prevalent.
However,
by
adjusting
responsiveness
neurons,
adaptation
can
yield
homeostasis
and
stabilise
rates
at
fixed
levels,
despite
stimulus
statistics.
sensory
cortex,
is
typically
also
specific,
that
reduce
to
over-represented
stimuli,
but
maintain
even
increase
far
from
ones.
Here,
we
present
a
normative
explanation
grounded
efficient
coding
principle,
showing
this
yields
an
optimal
trade-off
between
fidelity
metabolic
cost
neural
firing.
Unlike
previous
theories,
formulate
problem
computation-agnostic
manner,
enabling
our
framework
apply
periphery.
We
then
general
Distributed
Distributional
Codes,
specific
computational
theory
representations
serving
Bayesian
inference.
demonstrate
how
homeostatic
coding,
combined
with
such
representations,
provides
for
stimulus-specific
widely
observed
across
brain,
scheme
be
accomplished
divisive
normalisation
adaptive
weights.
Further,
develop
model
within
framework,
fitting
it
previously
published
experimental
data,
quantitatively
account
measures
adaption
primary
visual
cortex.
Current Research in Neurobiology,
Journal Year:
2023,
Volume and Issue:
5, P. 100101 - 100101
Published: Jan. 1, 2023
Optogenetics
has
been
a
promising
and
developing
technology
in
systems
neuroscience
throughout
the
past
decade.
It
difficult
though
to
reliably
establish
potential
behavioral
effects
of
optogenetic
perturbation
neural
activity
nonhuman
primates.
This
poses
challenge
on
future
optogenetics
humans
as
concepts
need
be
developed
primates
first.
Here,
I
briefly
summarize
viable
approaches
taken
improve
primate
optogenetics,
then
focus
one
approach:
improvements
measurement
behavior.
bring
examples
from
visual
behavior
show
how
choice
method
might
conceal
large
effects.
will
discuss
"cortical
detection"
task
detail
an
example
sensitive
that
can
record
cortical
stimulation
with
high
fidelity.
Finally,
encouraged
by
rich
scientific
landscape
ahead
invite
developers
chronically
implantable
devices
designed
for
simultaneous
recording
intervention
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Sept. 14, 2023
Abstract
The
relationship
between
neurons’
input
and
spiking
output
is
central
to
brain
computation.
Studies
in
vitro
anesthetized
animals
suggest
nonlinearities
emerge
cells’
input-output
(activation)
functions
as
network
activity
increases,
yet
how
neurons
transform
inputs
vivo
has
been
unclear.
Here,
we
characterize
cortical
principal
activation
awake
mice
using
two-photon
optogenetics.
We
deliver
fixed
at
the
soma
while
varies
with
sensory
stimuli.
find
responses
optogenetic
are
nearly
unchanged
excited,
reflecting
a
linear
response
regime
above
resting
point.
In
contrast,
dramatically
attenuated
by
suppression.
This
attenuation
powerful
means
filter
arriving
suppressed
cells,
privileging
other
excited
neurons.
These
results
have
two
major
implications.
First,
somatic
neural
accord
used
recent
machine
learning
systems.
Second,
IO
can
—
not
only
do
stimuli
change
outputs,
but
these
changes
also
affect
input,
attenuating
some
leaving
others
unchanged.
Significance
statement
How
their
into
outputs
fundamental
building
block
of
Past
studies
measured
(IO)
or
states.
measure
intact
brain,
where
ongoing
influence
input.
Using
state-of-the-art
methods
precise
near
cell
body,
soma,
discover
supralinear-to-linear
function,
contrary
previous
findings
threshold-linear,
strongly
saturating,
power
law
functions.
function
shape
allows
decrease
to,
filter,
they
below
firing
rates,
computation
term
attenuation-by-suppression.
Cell Reports,
Journal Year:
2023,
Volume and Issue:
42(10), P. 113185 - 113185
Published: Sept. 28, 2023
The
spontaneous
firing
of
neurons
is
modulated
by
brain
state.
Here,
we
examine
how
such
modulation
impacts
the
overall
distribution
rates
in
neuronal
populations
neocortical,
hippocampal,
and
thalamic
areas
across
natural
pharmacologically
driven
state
transitions.
We
report
that
all
examined
combinations
area
transition
category,
structure
rate
similar,
with
almost
fast-firing
experiencing
proportionally
weak
modulation,
while
slow-firing
exhibit
high
inter-neuron
variability
magnitude,
leading
to
a
stronger
on
average.
further
demonstrate
this
linked
left-skewed
logarithmic
scale
recapitulated
bivariate
log-gamma,
but
not
Gaussian,
distributions.
Our
findings
indicate
preconfigured
log-rate
rigid
long
left
tail
malleable
generic
property
forebrain
circuits.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 28, 2024
What
are
the
principles
that
govern
responses
of
cortical
networks
to
their
inputs
and
emergence
these
from
recurrent
connectivity?
Recent
experiments
have
probed
questions
by
measuring
two-photon
optogenetic
perturbations
single
cells
in
mouse
primary
visual
cortex.
A
robust
theoretical
framework
is
needed
determine
implications
for
recurrence.
Here
we
propose
a
novel
analytical
approach:
formulation
dependence
cell-type-specific
connectivity
on
spatial
distance
yields
an
exact
solution
linear
perturbation
response
model
with
multiple
cell
types
space-
feature-dependent
connectivity.
Importantly
unlike
previous
approaches,
valid
regimes
strong
as
well
weak
intra-cortical
coupling.
Analysis
reveals
structure
implied
various
features
single-cell
responses,
such
surprisingly
narrow
radius
nearby
excitation
beyond
which
inhibition
dominates,
number
transitions
between
mean
thereafter,
feature
preferences.
Comparison
results
existing
data
constraints
connection
strengths
tuning
dependence.
Finally,
provide
experimental
predictions
regarding
inhibitory
neurons
modulation
neuronal
gain;
latter
can
explain
observed
differences
feature-tuning
presence
vs.
absence
stimuli.