Manual
sleep
stage
classification
relies
on
visual
inspection
of
30-second
windows
comprising
multi-sensor
measurements
The
ability
neural
networks
to
model
complex
relations
has
made
them
a
popular,
faster,
alternative.
However,
it
often
remains
unclear
which
parts
the
data
predominantly
contributed
model's
decision.
This
is
especially
ambiguous
in
staging,
where
coarse
labeling
per
may
assign
mixtures
class-specific
features
single
class.
To
boost
transparency
deep
classifiers,
we
propose
dynamic
discrete
attention
module
that
actively
selects
subset
input
space
aligned
with
class
label.
can
be
combined
typical
network,
and
additionally
serve
as
data-driven
tool
discover
specific
polysomnography
data.
We
validate
method
synthetic
patient
observe
only
small
from
window
required
retain
accurate
classification,
mechanism
boosts
performance.
Analysis
masks,
moreover,
shows
clear
adaptive
channel
selection.
Frontiers in Physiology,
Год журнала:
2024,
Номер
14
Опубликована: Янв. 5, 2024
Introduction:
Automated
sleep
staging
using
deep
learning
models
typically
requires
training
on
hundreds
of
recordings,
and
pre-training
public
databases
is
therefore
common
practice.
However,
suboptimal
stage
performance
may
occur
from
mismatches
between
source
target
datasets,
such
as
differences
in
population
characteristics
(e.g.,
an
unrepresented
disorder)
or
sensors
alternative
channel
locations
for
wearable
EEG).
Methods:
We
investigated
three
strategies
automated
single-channel
EEG
stager:
(i.e.,
the
original
dataset),
training-from-scratch
new
fine-tuning
dataset,
dataset).
As
we
used
F3-M2
healthy
subjects
(N
=
94).
Performance
different
was
evaluated
Cohen’s
Kappa
(
κ
)
eight
smaller
datasets
consisting
60),
patients
with
obstructive
apnea
(OSA,
N
insomnia
REM
behavioral
disorder
(RBD,
22),
combined
two
channels,
F3-F4.
Results:
No
observed
age-matched
average
across
.83
healthy,
.77
insomnia,
.74
OSA
subjects.
RBD
set,
where
data
availability
limited,
preferred
method
.67),
increase
.15
to
training-from-scratch.
In
presence
mismatches,
targeted
required,
either
through
fine-tuning,
increasing
.17
average.
Discussion:
found
that,
when
and/or
cause
performance,
a
approach
can
yield
similar
superior
compared
building
model
scratch,
while
requiring
sample
size.
contrast
OSA,
contains
characteristics,
inherent
pathology
age-related,
which
apparently
demand
training.
Journal of Sleep Research,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 12, 2025
ABSTRACT
Rapid‐eye‐movement
(REM)
sleep
behaviour
disorder
(RBD)
is
a
primary
strongly
associated
with
Parkinson's
disease.
Assessing
structure
in
RBD
important
for
understanding
the
underlying
pathophysiology
and
developing
diagnostic
methods.
However,
performance
of
automated
stage
classification
(ASSC)
models
considered
suboptimal
RBD,
both
utilising
neurological
signals
(“ExG”:
EEG,
EOG,
chin
EMG)
heart
rate
variability
combined
body
movements
(HRVm).
Here,
we
explore
this
underperformance
through
categorical
representation
macrostructure
(i.e.,
hypnogram)
that
leverages
probability
distribution
ASSCs
hypnodensity).
By
comparing
population
(
n
=
36)
to
sex‐
age‐matched
group
OSA
patients
chosen
their
anticipated
similarly
decreased
stability,
confirm
lower
4‐stage
ExG‐based
ASSC
(RBD:
κ
0.74,
OSA:
0.80)
HRVm‐based
0.50,
0.63).
Stages
showing
agreement
namely,
N1
+
N2
REM
sleep,
exhibited
elevated
ambiguity
hypnodensity,
indicating
more
ambiguous
distributions.
Limited
differences
bout
durations
between
suggested
instability
not
necessarily
driving
RBD.
transitions
showed
abrupt
changes
distribution,
while
had
continuous
profile,
possibly
complicating
classification.
Although
staging
remain
challenging,
hypnodensity
analysis
informative
characterisation
can
capture
potential
drivers
disagreement.
Applied Sciences,
Год журнала:
2025,
Номер
15(7), С. 3422 - 3422
Опубликована: Март 21, 2025
We
provide
new
insights
into
the
performance
of
camera-based
heart
and
respiration
rate
extraction
evaluate
its
usability
for
replacing
spot
checks
conducted
in
general
ward.
A
study
was
performed
comprising
36
ICU
patients
recorded
a
total
time
699
h.
The
5
beats/minute
agreement
between
camera
ECG-based
measurements
81.5%,
with
coverage
81.9%,
where
largest
gap
239
min.
challenges
encountered
monitoring
were
limited
visibility
patient’s
face
irregular
rates,
which
led
to
poor
camera-
measurements.
To
prevent
non-breathing
motion
from
causing
error
extraction,
we
developed
metric
used
detect
motion.
3
breaths/minute
contact-based
91.1%,
59.1%,
114
Encountered
morphology
signal
breathing.
While
few
need
be
overcome,
results
show
promise
as
replacement
these
vital
parameters
Sensors,
Год журнала:
2025,
Номер
25(8), С. 2596 - 2596
Опубликована: Апрель 20, 2025
Radars
are
promising
tools
for
contactless
vital
sign
monitoring.
As
a
screening
device,
radars
could
supplement
polysomnography,
the
gold
standard
in
sleep
medicine.
When
radar
is
placed
lateral
to
person,
signs
can
be
extracted
simultaneously
from
multiple
body
parts.
Here,
we
present
method
select
every
available
breathing
and
heartbeat
signal,
instead
of
selecting
only
one
optimal
signal.
Using
concurrent
signals
enhance
rate
robustness
accuracy.
We
built
an
algorithm
based
on
persistence
diagrams,
modern
tool
time
series
analysis
field
topological
data
analysis.
Multiple
criteria
were
evaluated
diagrams
detect
signals.
tested
feasibility
simultaneous
overnight
polysomnography
recordings
six
healthy
participants.
Compared
against
single
bin
selection,
selection
lead
improved
accuracy
both
(mean
absolute
error:
0.29
vs.
0.20
breaths
per
minute)
heart
1.97
0.66
beats
minute).
Additionally,
fewer
artifactual
segments
selected.
Furthermore,
distribution
chosen
along
aligned
with
basic
physiological
assumptions.
In
conclusion,
monitoring
benefit
achieved
by
selection.
The
provide
additional
information
Scientific Reports,
Год журнала:
2023,
Номер
13(1)
Опубликована: Июнь 6, 2023
This
study
describes
a
computationally
efficient
algorithm
for
4-class
sleep
staging
based
on
cardiac
activity
and
body
movements.
Using
an
accelerometer
to
calculate
gross
movements
reflective
photoplethysmographic
(PPG)
sensor
determine
interbeat
intervals
corresponding
instantaneous
heart
rate
signal,
neural
network
was
trained
classify
between
wake,
combined
N1
N2,
N3
REM
in
epochs
of
30
s.
The
classifier
validated
hold-out
set
by
comparing
the
output
against
manually
scored
stages
polysomnography
(PSG).
In
addition,
execution
time
compared
with
that
previously
developed
variability
(HRV)
feature-based
algorithm.
With
median
epoch-per-epoch
κ
0.638
accuracy
77.8%
achieved
equivalent
performance
when
HRV-based
approach,
but
50-times
faster
time.
shows
how
network,
without
leveraging
any
priori
knowledge
domain,
can
automatically
"discover"
suitable
mapping
movements,
stages,
even
patients
different
pathologies.
addition
high
performance,
reduced
complexity
makes
practical
implementation
feasible,
opening
up
new
avenues
diagnostics.
2022 44th Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC),
Год журнала:
2023,
Номер
unknown, С. 1 - 5
Опубликована: Июль 24, 2023
Camera-based
sleep
monitoring
is
an
emergent
research
topic
in
medicine.
The
feasibility
of
using
both
the
physiological
features
and
motion
measured
by
a
video
camera
for
staging
was
not
thoroughly
investigated.
In
this
paper,
we
built
camera-based
non-contact
setup
Institute
Respiratory
Diseases,
Shenzhen
People's
Hospital,
created
clinical
dataset
(nocturnal
data
11
adults)
including
expert-corrected
PSG
references
synchronized
with
video.
measurements
have
shown
high
correlations
PSG.
It
obtains
overall
Mean
Absolute
Error
(MAE)
1.5
bpm
heart-rate
(HR),
0.7
breathing-rate
(BR),
13.9
ms
variability
(HRV),
accuracy
93.5%
leg
detection.
statistical
analysis
indicates
that
averaged
HR
variations
BR
are
distinct
annotating
four
stages
(awake,
REM,
light
sleep,
deep
sleep).
HRV
parameter
(SDNN)
can
clearly
differentiate
rapid-eye-movement
(REM)
non-REM,
while
movement
distinctive
feature
separating
awake
sleep.
trial
demonstrated
joint
staging,
provides
insights
sleep-related
selection.
2022 IEEE/CVF Conference on Computer Vision and Pattern Recognition Workshops (CVPRW),
Год журнала:
2023,
Номер
unknown
Опубликована: Июнь 1, 2023
Conventional
sleep
monitoring
is
time-consuming,
expensive
and
uncomfortable,
requiring
a
large
number
of
contact
sensors
to
be
attached
the
patient.
Video
data
commonly
recorded
as
part
laboratory
assessment.
If
accurate
staging
could
achieved
solely
from
video,
this
would
overcome
many
problems
traditional
methods.
In
work
we
use
heart
rate,
breathing
rate
activity
measures,
all
derived
near-infrared
video
camera,
perform
stage
classification.
We
deep
transfer
learning
approach
scarcity,
by
using
an
existing
contact-sensor
dataset
learn
effective
representations
time
series.
Using
50
healthy
volunteers,
achieve
accuracy
73.4%
Cohen's
kappa
0.61
in
four-class
classification,
establishing
new
state-of-the-art
for
video-based
staging.
Scientific Reports,
Год журнала:
2023,
Номер
13(1)
Опубликована: Ноя. 30, 2023
Due
to
the
association
between
dysfunctional
maternal
autonomic
regulation
and
pregnancy
complications,
tracking
non-invasive
features
of
derived
from
wrist-worn
photoplethysmography
(PPG)
measurements
may
allow
for
early
detection
deteriorations
in
health.
However,
even
though
a
plethora
these
features-specifically,
describing
heart
rate
variability
(HRV)
morphology
PPG
waveform
(morphological
features)-exist
literature,
it
is
unclear
which
be
valuable
As
an
initial
step
towards
clarity,
we
compute
comprehensive
sets
HRV
morphological
nighttime
measurements.
From
these,
using
logistic
regression
stepwise
forward
feature
elimination,
identify
that
best
differentiate
healthy
pregnant
women
non-pregnant
women,
since
likely
capture
physiological
adaptations
necessary
sustaining
pregnancy.
Overall,
were
more
discriminating
than
(area
under
receiver
operating
characteristics
curve
0.825
0.74,
respectively),
with
systolic
pulse
wave
deterioration
being
most
single
feature,
followed
by
mean
(HR).
Additionally,
stratified
analysis
sleep
stages
found
calculated
only
periods
deep
enhanced
differences
two
groups.
In
conclusion,
postulate
addition
features,
also
useful
health
suggest
specific
included
future
research
concerning
Journal of Sleep Research,
Год журнала:
2023,
Номер
33(3)
Опубликована: Дек. 9, 2023
Summary
Non‐rapid
eye
movement
parasomnia
disorders,
also
called
disorders
of
arousal,
are
characterized
by
abnormal
nocturnal
behaviours,
such
as
confusional
arousals
or
sleep
walking.
Their
pathophysiology
is
not
yet
fully
understood,
and
objective
diagnostic
criteria
lacking.
It
known,
however,
that
behavioural
episodes
occur
mostly
in
the
beginning
night,
after
an
increase
slow‐wave
activity
during
sleep.
A
better
understanding
prospect
may
lead
to
new
insights
underlying
mechanisms
eventually
facilitate
diagnosis.
We
investigated
temporal
dynamics
transitions
from
52
patients
79
controls.
Within
patient
group,
non‐behavioural
N3
awakenings
were
distinguished.
Patients
showed
a
higher
probability
wake
up
bout
ended
than
controls,
this
increased
with
duration.
Bouts
longer
15
min
resulted
awakening
73%
34%
time
respectively.
Behavioural
reduced
over
cycles
due
reduction
reducing
ratio
between
awakenings.
In
first
two
cycles,
bouts
prior
significantly
shorter
advancing
patients,
Our
findings
provide
timing
both
N3,
which
result
prediction
potentially
prevention
episodes.
This
work,
moreover,
leads
more
complete
characterization
prototypical
hypnogram
parasomnias,
could
Hypnograms
contain
a
wealth
of
information
and
play
an
important
role
in
sleep
medicine.
However,
interpretation
the
hypnogram
is
difficult
task
requires
domain
knowledge
"clinical
intuition."
This
study
aimed
to
uncover
which
features
drive
by
physicians.
In
other
words,
make
explicit
physicians
implicitly
look
for
hypnograms.
Three
experts
evaluated
up
612
hypnograms,
indicating
normal
or
abnormal
structure
suspicion
disorders.
ElasticNet
convolutional
neural
network
classification
models
were
trained
predict
collected
expert
evaluations
using
stages
as
input.
The
several
measures,
including
accuracy,
Cohen's
kappa,
Matthew's
correlation
coefficient,
confusion
matrices.
Finally,
model
coefficients
visual
analytics
techniques
used
interpret
associate
with
evaluation.
Agreement
between
(Kappa
0.47
0.52)
similar
agreement
0.38
0.50).
Sleep
fragmentation,
measured
transitions
per
hour,
stage
distribution
identified
predictors
interpretation.
By
comparing
hypnograms
not
solely
on
epoch-by-epoch
basis,
but
also
these
more
specific
that
are
relevant
evaluation
experts,
performance
assessment
(automatic)
sleep-staging
surrogate
trackers
may
be
improved.
particular,
fragmentation
feature
deserves
attention
it
often
included
PSG
report,
existing
(wearable)
have
shown
relatively
poor
this
aspect.