Motor-commands decoding using peripheral nerve signals: a review

Hong, Keum‐Shik; Aziz, Nida; Ghafoor, Usman

doi:10.1088/1741-2552/aab383

Cited by 50 publications

(30 citation statements)

References 157 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Transcranial direct current stimulation (tDCS) is a technique used to deliver small amounts of electric current to modulate the excitability of neural populations in different regions of the brain [16]. This noninvasive stimulation technique has been increasingly applied to various brain regions of healthy as well as diseased subjects [17], because it is well tolerated, safe, and inexpensive compared to other techniques involving invasive stimulation [18][19][20][21] which is based on nerve signal information [22]. Several studies have used tDCS to investigate the polarity-specific effects that are not limited to the stimulated site [23][24][25][26][27].…”

Section: Introductionmentioning

confidence: 99%

Effects of HD‐tDCS on Resting‐State Functional Connectivity in the Prefrontal Cortex: An fNIRS Study

2018

Self Cite

View full text Add to dashboard Cite

Functional connectivity is linked to several degenerative brain diseases prevalent in our aging society. Electrical stimulation is used for the clinical treatment and rehabilitation of patients with many cognitive disorders. In this study, the effects of high-definition transcranial direct current stimulation (HD-tDCS) on resting-state brain networks in the human prefrontal cortex were investigated by using functional near-infrared spectroscopy (fNIRS). The intrahemispheric as well as interhemispheric connectivity changes induced by 1 mA HD-tDCS were examined in 15 healthy subjects. Pearson correlation coefficient-based correlation matrices were generated from filtered time series oxyhemoglobin (ΔHbO) signals and converted into binary matrices. Common graph theory metrics were computed to evaluate the network changes. Systematic interhemispheric, intrahemispheric, and intraregional connectivity analyses demonstrated that the stimulation positively affected the resting-state connectivity in the prefrontal cortex. The poststimulation connectivity was increased throughout the prefrontal region, while focal HD-tDCS effects induced an increased rate of connectivity in the stimulated hemisphere. The graph theory metrics clearly distinguished the prestimulation and poststimulation networks for a range of thresholds. The results of this study suggest that HD-tDCS can be used to increase functional connectivity in the prefrontal cortex. The increase in functional connectivity can be explored clinically for neurorehabilitation of patients with degenerative brain diseases.

show abstract

Section: Introductionmentioning

confidence: 99%

Effects of HD‐tDCS on Resting‐State Functional Connectivity in the Prefrontal Cortex: An fNIRS Study

2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…These neuroimaging modalities can also be used to provide patients a means of communication with the real world through a brain–computer interface (BCI). The main role of the BCI is to translate brain signals and generate reliable commands with high accuracy to control external devices like a robotic arm/leg or a wheelchair in a real environment for patients ( Mcfarland and Wolpaw, 2010 , 2011 ; Nicolas-Alonso and Gomez-Gil, 2012 ; Ortiz-Rosario and Adeli, 2013 ; Muller-Putz et al, 2015 ; Hong et al, 2018a ). Among all HR-based modalities, fMRI and fNIRS can be used for non-invasive BCI applications ( Naito et al, 2007 ; Matthews et al, 2008 ; Sitaram et al, 2009 ; Sokunbi et al, 2014 ).…”

Section: Introductionmentioning

confidence: 99%

Existence of Initial Dip for BCI: An Illusion or Reality

Hong

Zafar

2018

Front. Neurorobot.

Self Cite

View full text Add to dashboard Cite

A tight coupling between the neuronal activity and the cerebral blood flow (CBF) is the motivation of many hemodynamic response (HR)-based neuroimaging modalities. The increase in neuronal activity causes the increase in CBF that is indirectly measured by HR modalities. Upon functional stimulation, the HR is mainly categorized in three durations: (i) initial dip, (ii) conventional HR (i.e., positive increase in HR caused by an increase in the CBF), and (iii) undershoot. The initial dip is a change in oxygenation prior to any subsequent increase in CBF and spatially more specific to the site of neuronal activity. Despite additional evidence from various HR modalities on the presence of initial dip in human and animal species (i.e., cat, rat, and monkey); the existence/occurrence of an initial dip in HR is still under debate. This article reviews the existence and elusive nature of the initial dip duration of HR in intrinsic signal optical imaging (ISOI), functional magnetic resonance imaging (fMRI), and functional near-infrared spectroscopy (fNIRS). The advent of initial dip and its elusiveness factors in ISOI and fMRI studies are briefly discussed. Furthermore, the detection of initial dip and its role in brain-computer interface using fNIRS is examined in detail. The best possible application for the initial dip utilization and its future implications using fNIRS are provided.

show abstract

“…Moreover, the use of q-step-head prediction with improved fitting can help in the hybridization of fNIRS with other rapid modalities such as EEG. Nevertheless, further research is still required to improve the fitting of the predicted fNIRS signals with an accuracy more than 90% using advanced signal processing (Ghafoor et al, 2017;Chen et al, 2018;Hong et al, 2018a) and adaptive algorithms (Iqbal et al, 2018;Nguyen Q. C. et al, 2018). In the future, other types of kernels should also be investigated for further improvement of the predicted fNIRS signals.…”

Section: Discussionmentioning

confidence: 99%

Reduction of Onset Delay in Functional Near-Infrared Spectroscopy: Prediction of HbO/HbR Signals

Zafar

Hong

2020

Front. Neurorobot.

Self Cite

View full text Add to dashboard Cite

An intrinsic problem when using hemodynamic responses for the brain-machine interface is the slow nature of the physiological process. In this paper, a novel method that estimates the oxyhemoglobin changes caused by neuronal activations is proposed and validated. In monitoring the time responses of blood-oxygen-level-dependent signals with functional near-infrared spectroscopy (fNIRS), the early trajectories of both oxy-and deoxy-hemoglobins in their phase space are scrutinized. Furthermore, to reduce the detection time, a prediction method based upon a kernel-based recursive least squares (KRLS) algorithm is implemented. In validating the proposed approach, the fNIRS signals of finger tapping tasks measured from the left motor cortex are examined. The results show that the KRLS algorithm using the Gaussian kernel yields the best fitting for both HbO (i.e., 87.5%) and HbR (i.e., 85.2%) at q = 15 steps ahead (i.e., 1.63 s ahead at a sampling frequency of 9.19 Hz). This concludes that a neuronal activation can be concluded in about 0.1 s with fNIRS using prediction, which enables an almost real-time practice if combined with EEG.

show abstract

Motor-commands decoding using peripheral nerve signals: a review

Cited by 50 publications

References 157 publications

Effects of HD‐tDCS on Resting‐State Functional Connectivity in the Prefrontal Cortex: An fNIRS Study

Effects of HD‐tDCS on Resting‐State Functional Connectivity in the Prefrontal Cortex: An fNIRS Study

Existence of Initial Dip for BCI: An Illusion or Reality

Reduction of Onset Delay in Functional Near-Infrared Spectroscopy: Prediction of HbO/HbR Signals

Contact Info

Product

Resources

About