Functional NIRS to detect covert consciousness in neurocritical patients

Bicciato, Giulio; Narula, Gagan; Brandi, Giovanna; Eisele, Amanda; Schulthess, Sven; Friedl, Susanne; Willms, Jan; Westphal, Laura P; Keller, Emanuela

doi:10.1016/j.clinph.2022.10.002

Cited by 7 publications

(2 citation statements)

References 54 publications

(60 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The oxy-hemoglobin (HbO) signal was estimated from optical density, which was measured by the fNIRS system using the NIRS-SPM toolbox 28 in MATLAB. A band-pass filter (0.01 to 2 Hz) was used as the preprocessing of the raw HbO signals to maintain the low-frequency oscillation, respiration, and cardiac information in fNIRS signals 46 , 47 . Inter-brain neuronal synchrony was estimated using the PLV.…”

Section: Methodsmentioning

confidence: 99%

“…A band-pass filter (0.01 to 2 Hz) was used as the preprocessing of the raw HbO signals to maintain the low-frequency oscillation, respiration, and cardiac information in fNIRS signals. 46 , 47 Inter-brain neuronal synchrony was estimated using the PLV. It can detect synchrony in a precise frequency range between two recording sites, uses responses to a repeated stimulus, and searches for latencies at which the phase difference between the signals varies minimally across trials.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

HyperOptoNet: a MATLAB-based toolbox for inter-brain neuronal synchrony analysis using fNIRS hyperscanning

Lee

Shin

et al. 2023

Neurophoton.

View full text Add to dashboard Cite

Significance: We developed a MATLAB-based toolbox for the analysis of inter-brain synchrony (IBS) and performed an experimental study to confirm its performance. To the best of our knowledge, this is the first toolbox for IBS based on functional near-infrared spectroscopy (fNIRS) hyperscanning data that visually shows the results on two three-dimensional (3D) head models.Aim: Research on IBS using fNIRS hyperscanning is a nascent but expanding field. Although various analysis toolboxes for fNIRS exist, none can show inter-brain neuronal synchrony on a 3D head model. In 2019 and 2020, we released two MATLAB toolboxes named OptoNet I and II, which have helped researchers to analyze functional brain networks using fNIRS. We developed a MATLAB-based toolbox named HyperOptoNet to overcome the limitation of the previous OptoNet series. Approach:The developed HyperOptoNet can easily analyze inter-brain cortical connectivity using fNIRS hyperscanning signals simultaneously measured from two people at the same time. The connectivity results can be easily recognized by representing inter-brain neuronal synchrony with colored lines that are visually expressed on two standard head models.Results: To evaluate the performance of the developed toolbox, we conducted an fNIRS hyperscanning study of 32 healthy adults. The fNIRS hyperscanning data were measured while the subjects performed traditional, paper-and-pencil-based, cognitive tasks or interactive, computerassisted, cognitive tasks (ICT). The results visualized different inter-brain synchronization patterns according to the interactive nature of the given tasks; a more extensive inter-brain network was seen with the ICT. Conclusions:The developed toolbox has good performance of IBS analysis and helps even unskilled researchers to easily analyze fNIRS hyperscanning data.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

HyperOptoNet: a MATLAB-based toolbox for inter-brain neuronal synchrony analysis using fNIRS hyperscanning

Lee

Shin

et al. 2023

Neurophoton.

View full text Add to dashboard Cite

show abstract

Naturalistic auditory stimuli with fNIRS prefrontal cortex imaging: A potential paradigm for disorder of consciousness diagnostics (a study with healthy participants)

Mizrahi

2023

Neuropsychologia

View full text Add to dashboard Cite

Low frequency oscillations reflect neurovascular coupling and disappear after cerebral death

Schulthess,

Friedl,

Narula

et al. 2024

Sci Rep

View full text Add to dashboard Cite

Spectrum power analysis in the low frequency oscillations (LFO) region of functional near infrared spectroscopy (fNIRS) is a promising method to deliver information about brain activation and therefore might be used for prognostication in patients with disorders of consciousness in the neurocritical care unit alongside with established methods. In this study, we measure the cortical hemodynamic response measured by fNIRS in the LFO region following auditory and somatosensory stimulation in healthy subjects. The significant hemodynamic reaction in the contralateral hemisphere correlation with the physiologic electric response suggests neurovascular coupling. In addition, we investigate power spectrum changes in steady state measurements of cerebral death patients and healthy subjects in the LFO region, the frequency of the heartbeat and respiration. The spectral power within the LFO region was lower in the patients with cerebral death compared to the healthy subjects, whereas there were no differences in spectral power for physiological activities such as heartbeat and respiration rate. This finding indicates the cerebral origin of our low frequency measurements. Therefore, LFO measurements are a potential method to detect brain activation in patients with disorders of consciousness and cerebral death. However, further studies in patients are needed to investigate its potential clinical use.

show abstract

Functional NIRS to detect covert consciousness in neurocritical patients

Cited by 7 publications

References 54 publications

HyperOptoNet: a MATLAB-based toolbox for inter-brain neuronal synchrony analysis using fNIRS hyperscanning

HyperOptoNet: a MATLAB-based toolbox for inter-brain neuronal synchrony analysis using fNIRS hyperscanning

Naturalistic auditory stimuli with fNIRS prefrontal cortex imaging: A potential paradigm for disorder of consciousness diagnostics (a study with healthy participants)

Low frequency oscillations reflect neurovascular coupling and disappear after cerebral death

Contact Info

Product

Resources

About