Task-specific invariant representation in auditory cortex
eLife,
Год журнала:
2023,
Номер
12
Опубликована: Авг. 31, 2023
Categorical
sensory
representations
are
critical
for
many
behaviors,
including
speech
perception.
In
the
auditory
system,
categorical
information
is
thought
to
arise
hierarchically,
becoming
increasingly
prominent
in
higher-order
cortical
regions.
The
neural
mechanisms
that
support
this
robust
and
flexible
computation
remain
poorly
understood.
Here,
we
studied
sound
ferret
primary
non-primary
cortex
while
animals
engaged
a
challenging
discrimination
task.
Population-level
decoding
of
simultaneously
recorded
single
neurons
revealed
task
engagement
caused
emerge
cortex.
cortex,
general
enhancement
was
not
specific
task-relevant
categories.
These
findings
consistent
with
mixed
selectivity
models
disentanglement,
which
early
regions
build
an
overcomplete
representation
world
allow
downstream
brain
flexibly
selectively
read
out
behaviorally
relevant,
information.
Язык: Английский
Unexpected suppression of neural responses to natural foreground versus background sounds in auditory cortex
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Ноя. 21, 2023
Abstract
In
everyday
hearing,
listeners
encounter
complex
auditory
scenes
containing
overlapping
sounds
that
must
be
grouped
into
meaningful
sources,
or
streamed,
to
perceived
accurately.
A
common
example
of
this
problem
is
the
perception
a
behaviorally
relevant
foreground
stimulus
(speech,
vocalizations)
in
background
noise
(environmental,
machine
noise).
Studies
using
foreground/background
contrast
have
shown
high-order
areas
cortex
humans
pre-attentively
form
an
enhanced
representation
over
stimulus.
Achieving
invariant
requires
identifying
and
grouping
features
comprise
so
they
can
removed
from
foreground.
To
study
cortical
computations
underlying
concurrent
(BG)
(FG)
stimuli,
we
recorded
single
unit
responses
(AC)
ferrets
during
presentation
natural
sound
excerpts
these
two
categories.
primary
secondary
AC,
found
overall
suppression
when
BGs
FGs
were
presented
concurrently
relative
sum
same
stimuli
isolation.
Surprisingly,
percepts
emphasize
dynamic
FGs,
FG
suppressed
paired
BG
sound.
The
degree
could
explained
by
spectro-temporal
statistics
unique
each
Moreover,
systematic
degradation
decreased
as
categories
became
progressively
less
statistically
distinct.
strongly
units
AC
presence
reveals
novel
insight
how
acoustic
are
encoded
at
early
stages
processing.
Язык: Английский
Different state-dependence of population codes across cortex
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2024,
Номер
unknown
Опубликована: Май 26, 2024
During
perceptual
decision-making,
behavioral
performance
varies
with
changes
in
internal
states
such
as
arousal,
motivation,
and
strategy.
Yet
it
is
unknown
how
these
affect
information
coding
across
cortical
regions
involved
differing
aspects
of
sensory
perception
decision-making.
We
recorded
neural
activity
from
the
primary
auditory
cortex
(AC)
posterior
parietal
(PPC)
mice
performing
a
navigation-based
sound
localization
task.
then
modeled
transitions
strategies
used
during
task
performance.
Mice
transitioned
between
three
latent
decision-making
strategies:
an
'optimal'
state
two
'sub-optimal'
characterized
by
choice
bias
frequent
errors.
Performance
strongly
influenced
population
patterns
association
but
not
cortex.
Surprisingly,
individual
PPC
neurons
was
better
explained
external
inputs
variables
suboptimal
than
optimal
state.
Furthermore,
shared
variability
(coupling)
strongest
In
AC,
similarly
weak
all
states.
Together,
findings
indicate
that
more
linked
to
Язык: Английский
Convolutional neural network models describe the encoding subspace of local circuits in auditory cortex
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 8, 2024
Abstract
Auditory
cortex
encodes
information
about
nonlinear
combinations
of
spectro-temporal
sound
features.
Convolutional
neural
networks
(CNNs)
provide
an
architecture
for
generalizable
encoding
models
that
can
predict
time-varying
activity
evoked
by
natural
sounds
with
substantially
greater
accuracy
than
established
models.
However,
the
complexity
CNNs
makes
it
difficult
to
discern
computational
properties
support
their
improved
performance.
To
address
this
limitation,
we
developed
a
method
visualize
tuning
subspace
captured
CNN.
Single-unit
data
was
recorded
using
high
channel-count
microelectrode
arrays
from
primary
auditory
(A1)
awake,
passively
listening
ferrets
during
presentation
large
set.
A
CNN
fit
data,
replicating
approaches
previous
work.
measure
subspace,
dynamic
spectrotemporal
receptive
field
(dSTRF)
measured
as
locally
linear
filter
approximating
input-output
relationship
at
each
stimulus
timepoint.
Principal
component
analysis
then
used
reduce
very
set
filters
smaller
typically
requiring
2-10
account
90%
dSTRF
variance.
The
projected
into
neuron,
and
new
model
only
values.
able
spike
rate
nearly
accurately
full
Sensory
responses
could
be
plotted
in
providing
compact
visualization.
This
revealed
diversity
responses,
consistent
contrast
gain
control
emergent
invariance
modulation
phase.
Within
local
populations,
neurons
formed
sparse
representation
tiling
subspace.
Narrow
spiking,
putative
inhibitory
showed
distinct
patterns
may
reflect
position
cortical
circuit.
These
results
demonstrate
conceptual
link
between
establish
framework
interpretation
deep
learning-based
Significance
statement
mediates
discrimination
complex
Many
have
been
proposed
encoding,
varying
generality,
interpretability,
ease
fitting.
It
has
determine
if/what
different
functional
are
study
shows
two
families
models,
convolutional
same
properties,
important
analytical
accurate
easy
straightforward
interpret
(tuning
subspace).
Язык: Английский