Journal of Neural Engineering,
Journal Year:
2024,
Volume and Issue:
21(6), P. 066001 - 066001
Published: Oct. 18, 2024
Abstract
Objective.
Current
intracortical
brain-computer
interfaces
(iBCIs)
rely
predominantly
on
threshold
crossings
(‘spikes’)
for
decoding
neural
activity
into
a
control
signal
an
external
device.
Spiking
data
can
yield
high
accuracy
online
during
complex
behaviors;
however,
its
dependence
high-sampling-rate
collection
pose
challenges.
An
alternative
iBCI
is
the
local
field
potential
(LFP),
continuous-valued
that
be
acquired
simultaneously
with
spiking
activity.
However,
LFPs
are
seldom
used
alone
as
their
performance
has
yet
to
achieve
parity
spikes.
Approach.
Here,
we
present
strategy
improve
of
LFP-based
decoders
by
first
training
dynamics
model
use
reconstruct
firing
rates
underlying
data,
and
then
from
estimated
rates.
We
test
these
models
previously-collected
macaque
center-out
random-target
reaching
tasks
well
collected
human
participant
attempted
speech.
Main
results.
In
all
cases,
enables
rate
reconstruction
comparable
spiking-based
models.
addition,
enable
exceeding
approaching
applications
except
speech,
also
facilitate
direct
Significance.
Because
operate
lower
bandwidth
sampling
than
models,
our
findings
indicate
devices
designed
power
requirements
dependent
recorded
activity,
without
sacrificing
high-accuracy
decoding.
Nature,
Journal Year:
2023,
Volume and Issue:
620(7976), P. 1031 - 1036
Published: Aug. 23, 2023
Speech
brain-computer
interfaces
(BCIs)
have
the
potential
to
restore
rapid
communication
people
with
paralysis
by
decoding
neural
activity
evoked
attempted
speech
into
text
Nature Medicine,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 20, 2025
Abstract
People
with
paralysis
express
unmet
needs
for
peer
support,
leisure
activities
and
sporting
activities.
Many
within
the
general
population
rely
on
social
media
massively
multiplayer
video
games
to
address
these
needs.
We
developed
a
high-performance,
finger-based
brain–computer-interface
system
allowing
continuous
control
of
three
independent
finger
groups,
which
thumb
can
be
controlled
in
two
dimensions,
yielding
total
four
degrees
freedom.
The
was
tested
human
research
participant
tetraplegia
due
spinal
cord
injury
over
sequential
trials
requiring
fingers
reach
hold
targets,
an
average
acquisition
rate
76
targets
per
minute
completion
time
1.58
±
0.06
seconds—comparing
favorably
prior
animal
studies
despite
twofold
increase
decoded
More
importantly,
positions
were
then
used
virtual
quadcopter—the
number-one
restorative
priority
participant—using
brain-to-finger-to-computer
interface
allow
dexterous
navigation
around
fixed-
random-ringed
obstacle
courses.
expressed
or
demonstrated
sense
enablement,
recreation
connectedness
that
addresses
many
people
paralysis.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Jan. 21, 2023
Abstract
Speech
brain-computer
interfaces
(BCIs)
have
the
potential
to
restore
rapid
communication
people
with
paralysis
by
decoding
neural
activity
evoked
attempted
speaking
movements
into
text
1,2
or
sound
3,4
.
Early
demonstrations,
while
promising,
not
yet
achieved
accuracies
high
enough
for
of
unconstrainted
sentences
from
a
large
vocabulary
1–7
Here,
we
demonstrate
first
speech-to-text
BCI
that
records
spiking
intracortical
microelectrode
arrays.
Enabled
these
high-resolution
recordings,
our
study
participant,
who
can
no
longer
speak
intelligibly
due
amyotrophic
lateral
sclerosis
(ALS),
9.1%
word
error
rate
on
50
(2.7
times
fewer
errors
than
prior
state
art
speech
2
)
and
23.8%
125,000
(the
successful
demonstration
large-vocabulary
decoding).
Our
decoded
at
62
words
per
minute,
which
is
3.4
faster
record
any
kind
8
begins
approach
speed
natural
conversation
(160
minute
9
).
Finally,
highlight
two
aspects
code
are
encouraging
BCIs:
spatially
intermixed
tuning
articulators
makes
accurate
possible
only
small
region
cortex,
detailed
articulatory
representation
phonemes
persists
years
after
paralysis.
These
results
show
feasible
path
forward
using
BCIs
speak.
Existing
intracortical
brain
computer
interfaces
(iBCIs)
transform
neural
activity
into
control
signals
capable
of
restoring
movement
to
persons
with
paralysis.
However,
the
accuracy
'decoder'
at
heart
iBCI
typically
degrades
over
time
due
turnover
recorded
neurons.
To
compensate,
decoders
can
be
recalibrated,
but
this
requires
user
spend
extra
and
effort
provide
necessary
data,
then
learn
new
dynamics.
As
neurons
change,
one
think
underlying
intent
signal
being
expressed
in
changing
coordinates.
If
a
mapping
computed
between
different
coordinate
systems,
it
may
possible
stabilize
original
decoder's
from
behavior
without
recalibration.
We
previously
proposed
method
based
on
Generalized
Adversarial
Networks
(GANs),
called
'Adversarial
Domain
Adaptation
Network'
(ADAN),
which
aligns
distributions
latent
within
low-dimensional
manifolds.
we
tested
ADAN
only
very
limited
dataset.
Here
propose
Cycle-Consistent
(Cycle-GAN),
full-dimensional
recordings.
both
Cycle-GAN
data
multiple
monkeys
behaviors
compared
them
third,
quite
Procrustes
alignment
axes
provided
by
Factor
Analysis.
All
three
methods
are
unsupervised
require
little
making
practical
real
life.
Overall,
had
best
performance
was
easier
train
more
robust
than
ADAN,
ideal
for
stabilizing
systems
time.
Nature Neuroscience,
Journal Year:
2023,
Volume and Issue:
27(1), P. 196 - 207
Published: Nov. 30, 2023
Brain-machine
interfaces
(BMIs)
enable
people
living
with
chronic
paralysis
to
control
computers,
robots
and
more
nothing
but
thought.
Existing
BMIs
have
trade-offs
across
invasiveness,
performance,
spatial
coverage
spatiotemporal
resolution.
Functional
ultrasound
(fUS)
neuroimaging
is
an
emerging
technology
that
balances
these
attributes
may
complement
existing
BMI
recording
technologies.
In
this
study,
we
use
fUS
demonstrate
a
successful
implementation
of
closed-loop
ultrasonic
BMI.
We
streamed
data
from
the
posterior
parietal
cortex
two
rhesus
macaque
monkeys
while
they
performed
eye
hand
movements.
After
training,
controlled
up
eight
movement
directions
using
also
developed
method
for
pretraining
previous
sessions.
This
enabled
immediate
on
subsequent
days,
even
those
occurred
months
apart,
without
requiring
extensive
recalibration.
These
findings
establish
feasibility
BMIs,
paving
way
new
class
less-invasive
(epidural)
generalize
extended
time
periods
promise
restore
function
neurological
impairments.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: Feb. 8, 2024
People
with
paralysis
express
unmet
needs
for
peer
support,
leisure
activities,
and
sporting
activities.
Many
within
the
general
population
rely
on
social
media
massively
multiplayer
video
games
to
address
these
needs.
We
developed
a
high-performance
finger
brain-computer-interface
system
allowing
continuous
control
of
3
independent
groups
2D
thumb
movements.
The
was
tested
in
human
research
participant
over
sequential
trials
requiring
fingers
reach
hold
targets,
an
average
acquisition
rate
76
targets/minute
completion
time
1.58
±
0.06
seconds.
Performance
compared
favorably
previous
animal
studies,
despite
2-fold
increase
decoded
degrees-of-freedom
(DOF).
Finger
positions
were
then
used
4-DOF
velocity
virtual
quadcopter,
demonstrating
functionality
both
fixed
random
obstacle
courses.
This
approach
shows
promise
controlling
multiple-DOF
end-effectors,
such
as
robotic
or
digital
interfaces
work,
entertainment,
socialization.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: March 20, 2024
Task
errors
are
used
to
learn
and
refine
motor
skills.
We
investigated
how
task
assistance
influences
learned
neural
representations
using
Brain-Computer
Interfaces
(BCIs),
which
map
activity
into
movement
via
a
decoder.
analyzed
cortex
as
monkeys
practiced
BCI
with
decoder
that
adapted
improve
or
maintain
performance
over
days.
The
dimensionality
of
the
population
neurons
controlling
remained
constant
increased
learning,
counter
expected
trends
from
learning.
Yet,
time,
information
was
contained
in
smaller
subset
modes.
Moreover,
ultimately
stored
modes
occupied
small
fraction
variance.
An
artificial
network
model
suggests
adaptive
decoders
contribute
forming
these
compact
representations.
Our
findings
show
assistive
manipulate
error
for
long-term
learning
computations,
like
credit
assignment,
informs
our
understanding
has
implications
designing
real-world
BCIs.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Feb. 4, 2023
Abstract
Intracortical
brain-computer
interfaces
(iBCIs)
require
frequent
recalibration
to
maintain
robust
performance
due
changes
in
neural
activity
that
accumulate
over
time.
Compensating
for
this
nonstationarity
would
enable
consistently
high
without
the
need
supervised
periods,
where
users
cannot
engage
free
use
of
their
device.
Here
we
introduce
a
hidden
Markov
model
(HMM)
infer
what
targets
are
moving
toward
during
iBCI
use.
We
then
retrain
system
using
these
inferred
targets,
enabling
unsupervised
adaptation
changing
activity.
Our
approach
outperforms
state
art
large-scale,
closed-loop
simulations
two
months
and
with
human
user
one
month.
Leveraging
an
offline
dataset
spanning
five
years
recordings,
further
show
how
recently
proposed
data
distribution-matching
approaches
fail
long
time
scales;
only
target-inference
methods
appear
capable
long-term
recalibration.
results
demonstrate
task
structure
can
be
used
bootstrap
noisy
decoder
into
highly-performant
one,
thereby
overcoming
major
barriers
clinically
translating
BCIs.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 3, 2025
Abstract
Individuals
with
severe
neurological
injuries
often
rely
on
assistive
technologies,
but
current
methods
have
limitations
in
accurately
decoding
multi-degree-of-freedom
(DoF)
movements.
Intracortical
brain-machine
interfaces
(iBMIs)
use
neural
signals
to
provide
a
more
natural
control
method,
currently
struggle
higher-DoF
movements—something
the
brain
handles
effortlessly.
It
has
been
theorized
that
simplifies
high-DoF
movement
through
muscle
synergies,
which
link
multiple
muscles
function
as
single
unit.
These
synergies
studied
using
dimensionality
reduction
techniques
like
principal
component
analysis
(PCA),
non-negative
matrix
factorization
(NMF),
and
demixed
PCA
(dPCA)
successfully
used
reduce
noise
improve
offline
decoder
stability
non-invasive
applications.
However,
their
effectiveness
improving
generalizability
for
implanted
recordings
across
varied
tasks
is
unclear.
Here,
we
evaluated
if
can
enhance
iBMI
performance
non-human
primates
performing
two-DoF
finger
task.
Specifically,
tested
PCA,
dPCA,
NMF
could
compress
denoise
data
generalization
tasks.
Our
results
showed
while
all
effectively
compressed
minimal
loss
accuracy,
none
improved
denoising.
Additionally,
of
enhanced
findings
suggest
aid
compression,
alone
it
may
not
reveal
“true”
space
needed
or
generalizability.
Further
research
required
determine
whether
are
optimal
framework
alternative
approaches
robustness
Significance
Statement
Many
researchers
believe
represent
fundamental
strategy
interface
(BMI)
performance.
extracted
techniques,
thought
simplify
complex
data,
efficiency
accuracy
BMI
systems.
In
our
study,
dexterous
We
found
these
high-dimensional
they
did
denoising
generalize
well
different
contexts.
Instead,
highest
was
achieved
when
available
suggesting
although
useful
adaptability