Advances in application of EEG-fNIRS technology in researches on neuropsychiatric disorders / 中国医学物理学杂志

Currently,electroencephalogram(EEG),functional near-infrared spectroscopy(fNIRS),and functional magnetic resonance imaging have been widely studied and applied to neuropsychiatric disorders.In recent years,the devices which can realize the simultaneous acquisition of EEG and fNIRS has been developed and gradually applied in the studies on neuropsychiatric disorders.The review provides an introduction of the techniques of synchronized detection and data analysis for EEG-fNIRS,summarizes the analysis methods and new findings of the recent studies of stroke,epilepsy,and other neuropsychiatric disorders using EEG-fNIRS,and also discusses the future research directions.

Improving the lower limb functioning and walking ability of stroke survivors with robot-assisted dual-task training / 中华物理医学与康复杂志

Objective:To explore the effects of dual task training assisted by a lower limb rehabilitation robot on lower extremity mobility and the walking ability of stroke survivors.Methods:Sixty-one stroke survivors were randomly divided into a control group and an experimental group with 30 in the control group and 31 in the experimental group. In addition to routine exercise training and physical therapy, both groups were given cognitive-motor dual task training 5 times a week for 3 weeks. But only in the experimental group was the dual task training assisted by a lower limb rehabilitation robot. Both groups′ lower limb motor function, walking ability, cognition, balance and ability in the activities of daily living were evaluated before and after the experiment using the Fugl-Meyer lower extremity assessment (FMA-LE), functional ambulation categories (FAC), the digital span test (DST), the Berg Balance Scale (BBS) and the Modified Barthel Index (MBI). Additionally, 6 survivors of a right hemisphere stroke from the experimental group received cognitive-motor dual task training both with and without the robotic assistance alternately. Near-infrared functional brain imaging was applied before and after the intervention, and the functional network connectivity of the resting brains was analyzed.Results:After the intervention the average FMA-LE, FAC, BBS and MBI scores had improved in both groups, with the improvement in the experimental group significantly better than in the control group on average. In terms of cognition there was no significant difference in the DST forward and backward assessment results between the two groups. The analysis of brain network functional connectivity showed that the intensity of functional connectivity between the left prefrontal cortex (PFC) and the left premotor cortex and supplementary motor cortex (PMC/SMA) increased significantly more, on average, after training assisted by the robot.Conclusion:Dual task training with the assistance of a lower limb rehabilitation robot can effectively improve the lower limb motor function, walking, balance and ability in the activities of daily living of stroke survivors. Enhanced functional connection of the PFC and the PMC/SMA in the healthy hemisphere induced by the robot may be the cause.

The effects of repetitive transcranial magnetic stimulation on the upper limb motor function of stroke survivors as measured by functional near infrared spectroscopy / 中华物理医学与康复杂志

Objective:To explore any effect of repeated transcranial magnetic stimulation (rTMS) on the upper limb motor function and cerebral cortex activation of stroke survivors.Methods:Sixty stroke survivors were randomly divided into an intervention group and a control group, each of 30. In addition to routine rehabilitation training (including drug therapy, comprehensive hemiplegic limb training and physical factor therapy), the intervention group received 15 minutes of rTMS daily, five days a week for 4 weeks while the control group was given false rTMS. Upper limb motor function was evaluated before and after the treatment using the Fugl Meyer upper limb motor function rating scale (FMA-UE). Functional near-infrared spectroscopy was used to detect and compare the activation (β values) of the prefrontal cortex, the motor cortex and the primary somatosensory cortex in the 2 groups. The correlation between the FMA-UE scores and the β values was quantified.Results:①There was no significant difference in the average FMA-UE scores between the two groups before the treatment. Afterward, though both groups′ average scores had increased significantly, there was significantly greater improvement in the treatment group. ②There was also no significant difference in average β value between the two groups before the experiment, but afterward the average βs of channels 27 and 13 in the intervention group were significantly higher than in the control group. Moreover, in patients with lesion in the left brain, the β-values of CH27 and CH13 were also significantly higher than the control group ( P<0.05). ③The FMA-UE scores of the intervention group were moderately correlated with the CH27 and CH13 β values, but those of the control group were only weakly correlated with the β values of CH27. Conclusion:Transcranial magnetic stimulation activates a lesioned left brain region, improving upper limb motor function. The improvement is correlated with the activation of the left prefrontal cortex and the left primary somatosensory cortex.

Study on the Evolution Principles of Traditional Chinese Medicine syndromes and fNIRS Cerebral Hemodynamic Characteristics in Patients with Alzheimer's Disease / 中医杂志

ObjectiveTo explore the evolution principles of symptoms including deficiency， phlegm and blood stasis， and of the functional near-infrared spectroscopy （fNIRS） cerebral hemodynamic characteristics at various stages in patients of Alzheimer's disease. MethodsA total of 497 patients with complaint of memory loss were included， and were divided into subjective cognitive decline （SCD） group （198 participants）， mild cognitive impairment （MCI） group （228 participants） and dementia （AD） group （71 participants）. Neuropsychological evaluation， traditional Chinese medicine （TCM） syndrome investigation， and fNIRS data collection of prefrontal cortex were performed in each group. Descriptive statistics were used to analyze the distribution of TCM syndromes and the difference of TCM syndrome scores in each group； logistic regression was used to analyze the influence of TCM syndromes on the incidence of the patients； association rules were used to analyze the TCM syndromes of the patients； the hemodynamic characteristics of fNIRS in the prefrontal cortex of each group were compared. ResultsKidney essence deficiency syndrome was the dominant syndrome in all stages of AD. There were statistically significant differences in the distribution frequency of kidney essence deficiency， phlegm turbidity obstructing orifices， blood stasis obstructing collaterals， qi and blood deficiency， heat toxin in the interior， and fu-organ stagnation and turbidity retention syndromes among the three groups （P＜0.01）， and the scores of kidney essence deficiency syndrome among the three groups were statistically significant （P＜0.01）. Logistic regression analysis showed that kidney essence deficiency， and qi and blood deficiency syndromes were the main risk factors for the SCD group （P＜0.05）， phlegm turbidity obstructing orifices syndrome was the main risk factor for the MCI group （P＜0.05）， and heat toxin in the interior， and fu-organ stagnation and turbidity retention syndromes were the main risk factors for the AD group （P＜0.05）. The association rule analysis showed that the combination of kidney essence deficiency plus phlegm turbidity obstructing orifices had the highest support （33.33%） in the SCD group， and the combination of kidney essence deficiency plus blood stasis obstructing collaterals had the highest support （32.90% and 52.13%） in both the MCI and AD group. The prefrontal fNIRS results showed that the mean ∆HbO2 concentration in the left dorsolateral prefrontal cortex （LDLPFC） decreased sequentially among the three groups （P＜0.05）， and the mean ∆HbO2 concentration in the LDLPFC was negatively correlated with the MoCA score among the three groups （r = -0.142， P＜0.05）. Further analysis showed that the mean ∆HbO2 concentration in the LDLPFC of patients with kidney essence deficiency syndrome were statistically significant differences among the three groups （P＜0.05）. ConclusionKidney deficiency is the basis of the pathogenesis of AD， and the key brain area damaged is the LDLPFC. Turbid pathogens such as phlegm and blood stasis are the pathological factors that aggravate the disease， and the syndromes of AD show the evolution law of deficiency and excess as “kidney deficiency→phlegm turbidity→blood stasis→turbid toxin”. The changes in prefrontal hemodynamics based on fNIRS are consistent with the changes in the characteristics of symptoms， which can be used to assess the degree of cognitive impairment in AD patients.

Research progress on brain functional near-infrared spectroscopy technology in the field of neonates / 中国当代儿科杂志

Functional near infrared spectroscopy (fNIRS) is an emerging neuroimaging tool that reflects the activity and function of brain neurons by monitoring changes in brain oxygen metabolism based on the neurovascular coupling mechanism. It is non-invasive and convenient, especially suitable for monitoring neonatal brain function. This article provides a comprehensive review of research related to the developmental patterns of brain networks concerning language, music, and emotions in neonates using fNIRS. It also covers brain network imaging in neonatal care, resting-state brain network connectivity patterns, and characteristics of brain functional imaging in disease states of neonates using fNIRS.

Recent advance in functional near-infrared spectroscopy in post-stroke depression and cognitive impairment / 中华神经医学杂志

In recent years, post-stroke depression (PSD) and post-stroke cognitive impairment (PSCI) have gradually attracted the attention of scholars as common stroke-related non-motor symptoms. As an emerging non-invasive neuroimaging tool, functional near-infrared spectroscopy (fNIRS) has been widely used in the study of neurological diseases, which can evaluate the functional status and recovery of these patients by monitoring changes in cerebral blood circulation and oxygenation signals; fNIRS is now being increasingly used in PSD and PSCI studies. This review mainly focuses on the research progress of fNIRS in identifying PSD and PSCI, exploring their neural mechanisms, and evaluating treatment effects, as well as advantages, disadvantages and future development prospects of fNIRS in clinical application, so as to provide some references for research on rehabilitation of affective disorders and cognitive disorders in stroke patients.

Characteristics of cerebral cortex activation in different swallowing periods based on near-infrared spectroscopy / 中国康复理论与实践

ObjectiveTo explore the cerebral cortex activation in different swallowing periods using functional near-infrared spectroscopy (fNIRS). MethodsFrom October to December 2023, a total of 18 healthy adults were recruited to perform four tasks of visual stimulation, chewing, tongue tip sliding and repeated swallowing during fNIRS acquisition, to calculate the cortical activation β values covering a total of 41 channels in frontal, parietal and occipital lobes. ResultsDuring the preoral period, the bilateral pre-motor and supplementary motor cortex (PSMC), bilateral inferior prefrontal gyrus, right visual association cortex (AVC), and left primary motor cortex (PMC) were significantly activated (P < 0.05). During oral preparation, the right pars triangularis (PTG), right frontal polar area (FPA), right dorsolateral prefrontal cortex (DPC), left primary somatosensory cortex (PSC), left PSMC and left PMC were significantly activated (P < 0.05). During the transition between oral and pharyngeal phases, bilateral PSMC and bilateral PMC were significantly activated (P < 0.05). Bilateral PSC, bilateral PTG, bilateral FPA, bilateral orbitofrontal area, bilateral PSMC, bilateral DPC and bilateral PMC were significantly activated during two consecutive periods of oral and pharyngeal phases (P < 0.05). ConclusionThe swallowing movement requires the coordination of the frontal, parietal and occipital cortex. The main activated brain areas are different in different swallowing stages, and the PSMC and PMC are involved in most swallowing stages.

Application of functional near-infrared spectroscopy in stroke: a visualized analysis / 中国康复理论与实践

ObjectiveTo explore the current status and frontier hotspots of functional near-infrared spectroscopy (fNIRS) in the field of stroke. MethodsRelevant literature on stroke and fNIRS from the Web of Science Core Collection (WoSCC) database was searched from its inception to July, 2023. VOSviewer, CiteSpace and Scimago were utilized for analysis of publication output, countries (regions) and institutions, international collaboration, co-cited references, co-occurring keywords and burst keywords. ResultsA total of 379 articles were included. The research activity in this field showed an overall upward trend with slight fluctuations in the early stage. Among the top five institutions by publication output, four were from China. Co-occurrence analysis revealed that Beihang University and Boston Children's Hospital were central in collaboration networks. This study involved 1 787 authors, with 120 core authors, in which the top five most cited authors were Li Zengyong, Li Wenhao, Huo Congcong, Dou Zulin and Song Ying. The publications in this field were primarily concentrated in disciplines such as neurology, psychiatry, ophthalmology and clinical medicine. Overlay visualization of journal co-citation networks demonstrated associations between medical, clinical, and neurology disciplines with psychology, education, and sociology. Co-occurrence and clustering analysis of keywords indicated research emphasis on stroke rehabilitation, integration of multiple technical modalities, and exploration of innovative training strategies and brain activation connectivity. The research evolution of fNIRS in the stroke domain revealed initial use of photodiode devices for cerebral ischemia reperfusion monitoring. Subsequent studies refined cortical activation through improved laser sources, avalanche photodiodes, single-task experimental designs and transcranial direct current stimulation. Later, research extended to whole-brain detection, multimodal stimulation and the combination of virtual reality technology with audiovisual stimulation, resulting in significantly enhanced brain activation. The application of brain-computer interface technology further facilitated direct restoration of motor function. ConclusionResearches in the field of stroke using fNIRS technology overall demonstrat a continuous upward trend. The researches focuse on post-stroke rehabilitation, integrating multimodal fusion, brain-computer interfaces, virtual reality, and sensory stimulation for real-time monitoring and personalized neurorehabilitation training strategies. It emphasizes interdisciplinary collaboration, expanding innovative research and the application of new technologies.

Brain network during balance in older adults: a functional near-infrared spectroscopy study / 中国康复理论与实践

ObjectiveTo study the brain network during balance control tasks in older adults. MethodsFrom January to April, 2022, 22 healthy young adults and 20 healthy older adults were recruited from the Fifth Affiliated Hospital of Guangzhou Medical University and communities. They were asked to finish standing tasks on the plantar pressure plate with eyes opening and closing, while the functional connectivities (FC) of prefrontal cortex (PFC) and primary motor cortex (PMC) were measured with functional near-infrared spectroscopy. ResultsCompared with the young adults, the area of the ellipse (Z = -2.884, P < 0.01) and the maximum swing (Z = -2.481, P < 0.05) increased in the older adults as eyes closing. During the standing task, the intra-FC of left (t = 2.978, P < 0.01) and right (Z = -3.123, P < 0.01) PFC decreased in the older adults, and the inter-FC of right PMC to left PFC (t = 2.087, P < 0.05) and right PFC to left PFC (t = 3.471, P < 0.001) decreased, too. ConclusionThe FC of PFC decreased in healthy older adults during balance control tasks, which may be a indicator for aging brain.

Cerebral hemodynamic signals as healthy people swallow hot and cold water: An infrared spectroscopy study / 中华物理医学与康复杂志

Objective:To explore the change in cerebral blood flow when healthy subjects swallow hot and ice water, and to verify the sensitivity of functional near-infrared spectroscopy (fNIRS) in identifying liquid temperatures while swallowing as a basis for applying it in diagnosis and intervention.Methods:Sixteen healthy subjects swallowed hot and ice water in randomized order while the process was recorded using fNIRS. The activation at rest and when swallowing hot and ice water was compared pairwise.Results:Compared with the resting state, 19 channels were activated during the swallowing of the hot and ice water. The common activated areas were S1, M1, PMC, SMA, Wernicke′s area, the somatosensory association cortex, the visual association cortex and the frontal eye field. However, the dorsal lateral prefrontal cortex was activated only when swallowing hot water, and the subcentral area was activated only when swallowing ice water. The SMA and PMC were significantly more activated when swallowing hot water than ice water.Conclusions:Multiple brain regions are activated and participate in regulating swallowing. The PMC and SMA areas can distinguish hot water from ice water swallowing.

Functional connectivity and regional spontaneous brain activity in a minimally-conscious state / 中华物理医学与康复杂志

Objective:To explore the characteristics of functional connectivity (FC) and regional spontaneous brain activity in patients in a minimally-conscious state (MCS).Methods:Resting-state functional near-infrared spectroscopy (rs-fNIRS) was used. Ten minimally-conscious patients were studied along with 12 healthy counterparts as healthy controls (HC). Five minutes of rs-fNIRS data were recorded from each subject and FC and the fractional amplitude of low-frequency fluctuations (fALFFs) of 53 channels were computed using the NIRS-KIT toolbox. The results were compared between the two groups.Results:Compared with the HC group, a significant decrease was observed in the average FC strength of seventeen channel pairs after false discovery rate (FDR) correction. Most were in the right and left frontal pole, as well as the dorsolateral prefrontal lobe. Compared with the HC group, the average fALFF values of Broca′s area (channel 2), the premotor cortex and the supplementary motor cortex (channels 4, 10, and 40), the dorsolateral prefrontal lobe (channels 6, 11, 25, 39), the eye motor area of the frontal lobe (channel 12) and the frontal pole (channels 23, 27, 36) were significantly greater in the MCS group. The fluctuations of the frontal pole (channel 19) were significantly less (after FDR correction).Conclusion:In an MCS spontaneous neural activity is over-active in the prefrontal lobe and some speech- and motor-related brain regions, and coordination of the internal prefrontal functional network is disordered.

A near-infrared spectroscopy study of brain resting state functional connectivity features of frontotemporal lobes in children with autism spectrum disorder / 中国神经精神疾病杂志

Objective To explore the features of frontotemporal lobes'resting-state functional connectivity(rsFC)in preschool children with autism spectrum disorders(ASD)based on functional near-infrared spectroscopy(fNIRS)and to explore the possible neurological markers for early identification of ASD.Methods Sixty-three preschool ASD children and 72 typical development(TD)children were enrolled.Selected bilateral dorsolateral prefrontal cortex(DLPFC),bilateral premotor cortex(PMC),and bilateral temporal lobe(TL)cortex as the regions of interest(ROI).Changes of Oxyhemoglobin in the 6 ROIs in resting-state were measured by using functional near-infrared spectroscopy(fNIRS).Compared the frontotemporal rsFC strength and calculate the laterality index(LI)between two groups.Results Compared with the TD group,rsFC strength was significantly lower in the ASD group(P<0.05),and the differences existed mainly within the left ROIs(0.21±0.11 vs.0.32±0.18),right ROIs(0.16±0.16 vs.0.30±0.14),bilateral DLPFCs(0.20±0.14 vs.0.39±0.17;0.15±0.13 vs.0.36±0.13),bilateral TLs(0.15±0.14 vs.0.28±0.17;0.14±0.15 vs.0.31±0.17),and between the 10 groups of ROIs-ROIs(including right DLPFC-left DLPFC,right DLPFC-right PMC,right DLPFC-left PMC,right DLPFC-right TL,right DLPFC-left TL,left DLPFC-right PMC,left DLPFC-left PMC,left DLPFC-right TL,left DLPFC-left TL,right TL-left TL).There were a significant differences in the rsFC's laterality index of DLPFC and whole-brain between the two groups(t=2.002,P=0.047;t=3.003,P=0.003),and the ASD group showed left-lateralized connectivity.Conclusion Frontotemporal lobe's resting-state functional connectivity is abnormal in preschool children with ASD,characterized by low short-range functional connectivity of bilateral DLPFCs and TLs,low long-range functional connectivity associated with DLPFCs,and left-lateralized connectivity.

Prefrontal cortex activation in women with perimenopausal depression: a functional near-infrared spectroscopy study / 中华行为医学与脑科学杂志

Objective:To explore the relative concentration changes of oxygenated hemoglobin (Oxy Hb) in the prefrontal cortex (PFC) and brain region activation during emotional face recognition tasks in women with perimenopausal depression.Methods:From February to April 2023, forty perimenopausal women were recruited, including 20 women with perimenopausal depression (experimental group) and 20 women with non-perimenopausal depression (control group). All participants were evaluated by the modified Kupperman score, 24-item Hamilton depression scale (HAMD-24), and patient health questionnaire (PHQ-9). Functional near-infrared spectroscopy (fNIRS) equipment was used to measure the relative concentration of Oxy-Hb in the PFC in two groups under the emotional face recognition task. Statistical analysis was performed by SPSS 26.0 software. Data were analyzed by a t-test, rank sum test, and Pearson correlation. Results:There were statistically significant differences in the results of the modified Kupperman score((23.20±3.66), (18.10±1.28)), HAMD-24((15.95±5.47), (3.35±1.84)), and PHQ-9(7.00(5.00, 10.75), 1.50(1.00, 3.00)) scales between the the experimental group and control group ( P<0.05). There was a positive correlation between the modified Kupperman score and the HAMD-24 score in the experimental group ( r=0.685, P=0.01). The reaction time of the experimental group in identifying negative and neutral emotional faces was statistically significant compared to the control group( t=4.01, 4.80, both P<0.05). Compared with identifying neutral emotions, PFC activation was stronger in the experimental group and control group when identifying negative emotions ( P<0.05). The PFC activation in the experimental group was stronger than that in the control group when identifying negative emotions ( P<0.05). There was no statistically significant difference in the activation level between the two groups when identifying neutral emotions ( P>0.05). Conclusion:Women with perimenopausal depression exhibit specificity in emotional processing, with increased PFC activation when identifying negative emotions, impaired emotional processing function of PFC, and dysfunction of aerobic metabolism.

Recent advance in functional near infrared spectroscopy in evaluating disorder of consciousness / 中华神经医学杂志

At present, neuroimaging and neuroelectrophysiology are the main objective detection techniques of brain consciousness; and neuroimaging includes functional magnetic resonance imaging (fMRI) and functional near-infrared spectroscopy (fNIRS). As a new non-invasive optical neuroimaging technology, fNIRS has more application prospects than fMRI: it can clear the cerebral cortex activation in resting state or different task states, such as real movement, motor imagination, or mental arithmetic; it can not only assess the consciousness horizontally, but also evaluate the effect of rehabilitation therapy vertically. In this paper, the application status of fNIRS in assessing consciousness of disorder is reviewed to explore new technical evaluation means for disorder of consciousness.

Brain function connectivity of patients with non-fluent aphasia after subacute stroke based on functional near infrared spectroscopy / 中华神经医学杂志

Objective:To explore the neural mechanism of language dysfunction in patients with subacute stroke using functional near-infrared spectroscopy (fNIRS).Methods:Sixteen patients with non-fluent aphasia after subacute stroke (aphasia group), 16 patients with non-aphasia after stroke (non-aphasia group), and 16 healthy middle-aged and elderly subjects (control group) were enrolled into our study. The 6-min resting-state data of fNIRS were collected. Four language-related regions, Broca area, Wernicke area, dorso lateral prefrontal cortex (DLPFC), and supplementary motor area (SMA), were selected as regions of interest (ROIs), and the whole brain functional connection strength and functional connection strength in ROIs and between each two ROIs were analyzed by NirSpark software.Results:Compared with the control group (0.53±0.15) and non-aphasia group (0.47±0.12), the aphasia group had significantly decreased whole brain functional connection strength (0.29±0.14, P<0.05). Compared with the control group and non-aphasia group, the aphasia group had significantly decreased functional connection strength in the left Wernicke area, right Wernicke area, left Broca area, left SMA area, right SMA area and left DLPFC area ( P<0.05, FDR). Compared with the control group and non-aphasia group, the aphasia group had significantly decreased functional connection strength in the right Wernicke-left Wernicke area, right Wernicke-right Broca area, right Wernicke-left Broca area, right Wernicke-right DLPFC area, right Wernicke-left DLPFC area, right Wernicke-right SMA area, right Wernicke-left SMA area, left Wernicke-right Broca area, left Wernicke-left Broca area, left Wernicke-right DLPFC area, left Wernicke-left DLPFC, left Wernicke-right SMA area, left Wernicke-left SMA area, right Broca-left Broca area, right Broca-left DLPFC area, right Broca-right SMA area, right Broca-left SMA area, left Broca-right DLPFC area, left Broca-left DLPFC area, left Broca-right SMA area, left Broca-left SMA area, right DLPFC-left DLPFC area, right DLPFC-right SMA area, right DLPFC-left SMA area, left DLPFC-right SMA area, left DLPFC-left SMA area, and right SMA-left SMA area ( P<0.05, FDR). Conclusion:Abnormal functional connectivity strength of the whole brain and language-related key brain areas might be the neural mechanism of language dysfunction in patients with non-fluent aphasia after subacute stroke.

Application of functional near-infrared spectroscopy in rehabilitation: a visualized analysis / 中国康复理论与实践

ObjectiveTo summarize the current situation, hot spots and frontiers of the application of functional near-infrared spectroscopy (fNIRS) in rehabilitation in recent ten years. MethodsLiterature related to the application of fNIRS in rehabilitation was retrieved from the core collection of Web of Science from January, 2003 to December, 2022, and the visualized analysis was performed by CiteSpace 6.1.R6 software. ResultsA total of 828 literatures were included. The annual publication volume was on the rise. The most prolific author was LI Zengyong. The most published country was the United States. And the most published institution was Karolinska Institute. Hot keywords included children, stroke, activation, quality of life, cerebral palsy, etc. The hot keywords of bursting intensity included early intervention, speech perception, cerebral palsy, plasticity, spinal cord injury, physical therapy, visual feedback, Parkinson's disease, etc. Cluster analysis suggested that in the past decade, the application of fNIRS in rehabilitation involved physical therapy, speech therapy, occupational therapy, pre-rehabilitation and early rehabilitation of surgery, mainly focusing on six themes: the rehabilitation of motor dysfunction after stroke, cognitive impairment, hearing and speech dysfunction, children with cerebral palsy, cardiopulmonary function monitoring in severe diseases and long-term nursing of chronic diseases. Among them, the application of fNIRS in neurological rehabilitation of stroke patients occupied a large proportion, which might be the current research hot spot and trend. ConclusionThe application of fNIRS in rehabilitation is on the rise. In the future, more attention should be paid to the application of fNIRS in the study of the injury and recovery mechanism of neurological disorders, especially the effects of various rehabilitation interventions on cortical plasticity and the etiology of neurological disorders.

Characteristics of cortical activation in older adults under cognition-balance dual tasks / 中国康复理论与实践

ObjectiveTo explore the characteristics of balance and cortical activation in older adults when performing cognition-balance dual tasks. MethodsFrom January to April, 2023, 20 healthy older adults were non-targeted recruited. They completed six tasks of close eyes & fixed platform (CF), close eyes & fixed platform & cognitive task (CFc), open eyes & sway-referenced platform (OS), open eyes & sway-referenced platform & cognitive task (OSc), close eyes & sway-referenced platform (CS), and close eyes & sway-referenced platform & cognitive task (CSc) on the Balance SD, wearing functional near-infrared spectroscopy caps. The overal stability index (OSI) was measured with Balance SD. The premotor cortex (PMC), sensorimotor cortex (SMC) and prefrontal cortex (PFC) were as regions of interest (ROIs), and the β values were calculated. ResultsThe OSI was more as CFc than as CF (Z = -2.014, P < 0.05), and was less as CSc than as CS (Z = -2.063, P < 0.05). The β values of bilateral ROIs were all more as CFc than as CF (|Z| > 2.464, |t| > 3.733, P < 0.05), and as OSc than as OS (|t| > 2.308, P < 0.05); the β value of the right SMC was more as CSc than as CS (t = -2.912, P < 0.05). The number of correct counts was less as CSc than as CFc and OSc (|Z| > 3.643, P < 0.001). ConclusionBalance has been impaired under dual tasks for older adults, while activation of cerebral cortex increases. However, for more difficult balance task, older adults would preferentially maintain postural balance under dual tasks, while cognitive performance decreases, which may be the results from no more activation of cerebral cortex under dual tasks.

Brain and muscle activation under mirror neuron-based training strategies: a near-infrared spectroscopy and surface electromyography study / 中国康复理论与实践

ObjectiveTo explore the neuromuscular control mechanism of training strategies based on mirror neuron system (MNS): action observation (AO), action execution (AE) and action imitation (AO+AE) using functional Near Infrared Spectroscopy (fNIRS) and surface electromyography (sEMG). MethodsFrom July, 2022 to February, 2023, 64 healthy adults were asked to finish four tasks: watching landscape video (control), watching landscape video and acting right wrist and hand extension (AE), watching right wrist and hand extension video (AO), and watching right wrist and hand extension video and acting right wrist and hand extension (AO+AE). A block design was adopted, five times a task in a block, eight cycles, random orders in videos and tasks. The activation of each channel and regions of interest (ROI, namely BA40, BA44, BA45, BA46, BA6 and BA7) in left MNS regions was detected with fNIRS synchronously, as well as the average electromyography (AEMG) of extensor digitorum and extensor carpi radialis with sEMG. ResultsCompared with the control condition, MNS activated in AO, AE and AO+AE conditions, and the intensities mildly increased in turn. Compared with the control condition, 15 channels activated in AO condition, 15 channels activated in AE condition, and all 20 channels activated in AO+AE condition; and the activation intensities of most channels were AO+AE > AE > AO. Four ROI, BA40, BA46, BA6 and BA7, activated in AO condition, all the six ROI activated in AE and AO+AE conditions, and the activation intensities of most ROI were AO+AE > AE > AO. The standardized AEMG of extensor digitorum and extensor carpi radialis were higher in AO+AE condition than in AE condition (|t| > 4.24, P < 0.001). ConclusionMNS has been activated during action observation, execution and imitation, and the ranges and intensities of activation increase in turn. The target muscles activate more during imitation than during execution. Synchronous application of fNIRS and sEMG is feasible in the study of neural mechanism of rehabilitation strategies based on mirror neuron theory.

Effect of upper limb robot-assisted therapy on upper limb function in stroke patients: based on functional near-infrared spectroscopy / 中国康复理论与实践

ObjectiveTo study the effect of upper limb robot-assisted therapy on upper limb function and cerebral cortex activation in stroke patients using functional near-infrared spectroscopy (fNIRS). MethodsFrom January, 2022 to January, 2023, 32 stroke patients in Zhejiang Rehabilitation Medical Center were randomly divided into control group (n = 16) and experimental group (n = 16). Both groups received routine neurological medication and routine rehabilitation. The control group received routine upper limb exercises, the experimental group received upper limb robot-assisted therapy. They were assessed with Fugl-Meyer Assessment-Upper Extremities (FMA-UE) and fNIRS (oxyhemoglobin, deoxyhemoglobin, and total hemoglobin) before and four weeks after treatment. NIRS_SPM was used for activation analysis, Homer2 was used for blood oxygen concentration analysis. ResultsAfter treatment, the score of FMA-UE increased in both groups (|t| > 5.910, P < 0.001), and was higher in the experimental group than in the control group (t = -2.348, P < 0.05). fNIRS activation results showed that, the activation increased in the experimental group after treatment in channel 17 (F = 9.354, P < 0.01), and it was more than that in the control group (F = 5.217, P < 0.05). fNIRS blood oxygen concentration results showed that, the blood oxygen concentration increased in the experimental group after treatment in channel 17 (F = 12.179, P < 0.01), and it was more than that in the control group (F = 4.883, P < 0.05). ConclusionThe upper limb robot-assisted therapy can improve the upper limb motor function and cerebral cortex activation of stroke patients.

Application of functional near-infrared spectroscopy in Parkinson disease / 中华行为医学与脑科学杂志

Parkinson disease (PD) is a common neurodegenerative disease with motor and non-motor symptoms that seriously affect the quality of life and social function of patients. The current non-invasive techniques in PD brain function studies mainly include functional magnetic resonance imaging and electroencephalography, which made it difficult to assess brain function under motor state or magnetoelectric treatment. As an emerging functional neuroimaging technique, functional near-infrared spectroscopy (fNIRS) can monitor the real movement-related cortical responses of PD patients in real time, providing a safe and non-invasive method with high ecological validity for direct monitoring of brain activity. This article presented a review of recent advances in the application of fNIRS technology in PD research, intending to provide new ideas for functional neuroimaging studies in PD. The results suggested that PD gait and balance deficits were closely associated with abnormal activation of the cerebral cortex, particularly the prefrontal cortex, involving a compensatory strategy of cortical cognitive resources for basal ganglia dysfunction. Drugs, deep brain stimulation, and other interventions could be applied to fNIRS techniques to evaluate neurorehabilitation effects and reveal the neural basis of intervention effects. This area of research is currently in its infancy, but the evidence provided supports for the translation of fNIRS into clinical practice. Future research should develop multimodal imaging techniques and in-depth studies of broad areas of the cerebral cortex to obtain more valuable findings for clinical practice.