Nature,
Journal Year:
2022,
Volume and Issue:
609(7926), P. 327 - 334
Published: Aug. 24, 2022
Abstract
In
the
hippocampus,
spatial
maps
are
formed
by
place
cells
while
contextual
memories
thought
to
be
encoded
as
engrams
1–6
.
Engrams
typically
identified
expression
of
immediate
early
gene
Fos
,
but
little
is
known
about
neural
activity
patterns
that
drive,
and
shaped
by,
in
behaving
animals
7–10
Thus,
it
unclear
whether
Fos-expressing
hippocampal
neurons
also
encode
correlates
with
affects
specific
features
code
11
Here
we
measured
CA1
calcium
imaging
monitoring
induction
mice
performing
a
hippocampus-dependent
learning
task
virtual
reality.
We
find
high
form
ensembles
highly
correlated
activity,
exhibit
reliable
fields
evenly
tile
environment
have
more
stable
tuning
across
days
than
nearby
non-Fos-induced
cells.
Comparing
neighbouring
without
function
using
sparse
genetic
loss-of-function
approach,
disrupted
less
decreased
selectivity
lower
across-day
stability.
Our
results
demonstrate
Fos-induced
contribute
codes
encoding
accurate,
spatially
uniform
itself
has
causal
role
shaping
these
codes.
may
therefore
link
two
key
aspects
function:
for
underlie
cognitive
maps.
Cell,
Journal Year:
2020,
Volume and Issue:
183(6), P. 1586 - 1599.e10
Published: Nov. 6, 2020
The
hippocampus
is
crucial
for
spatial
navigation
and
episodic
memory
formation.
Hippocampal
place
cells
exhibit
spatially
selective
activity
within
an
environment
have
been
proposed
to
form
the
neural
basis
of
a
cognitive
map
space
that
supports
these
mnemonic
functions.
However,
direct
influence
cell
on
behavior
has
not
yet
demonstrated.
Using
'all-optical'
combination
simultaneous
two-photon
calcium
imaging
optogenetics,
we
identified
selectively
activated
encoded
behaviorally
relevant
locations
in
virtual
reality
environment.
Targeted
stimulation
small
number
was
sufficient
bias
animals
during
task,
providing
causal
evidence
hippocampal
actively
support
memory.
Nature Communications,
Journal Year:
2020,
Volume and Issue:
11(1)
Published: Sept. 2, 2020
Abstract
The
formation
and
maintenance
of
spatial
representations
within
hippocampal
cell
assemblies
is
strongly
dictated
by
patterns
inhibition
from
diverse
interneuron
populations.
Although
it
known
that
inhibitory
synaptic
strength
malleable,
induction
long-term
plasticity
at
distinct
synapses
its
regulation
network
activity
not
well
understood.
Here,
we
show
parvalbumin
somatostatin
expressing
interneurons
undergo
depression
potentiation
respectively
(PV-iLTD
SST-iLTP)
during
physiological
patterns.
Both
forms
rely
on
T-type
calcium
channel
activation
to
confer
synapse
specificity
but
otherwise
employ
mechanisms.
Since
preferentially
target
perisomatic
distal
dendritic
regions
CA1
pyramidal
cells,
PV-iLTD
SST-iLTP
coordinate
a
reprioritisation
excitatory
inputs
entorhinal
cortex
CA3.
Furthermore,
circuit-level
modelling
reveals
cooperate
stabilise
place
cells
while
facilitating
representation
multiple
unique
environments
the
network.