oxy-Hb Changes Research Articles

Cortical activation during the verbal fluency task for obstructive sleep apnea patients with depressive symptoms: A multi-channel fNIRS study.

The aim of our study was to elucidate differences in brain activity patterns among obstructive sleep apnea (OSA) patients, OSA patients with depressive symptoms, and healthy controls (HCs). We also investigated the relationship between brain function and depression in OSA patients. A total of 95 subjects were included in the study, including 34 OSA patients without depressive symptoms, 31 OSA patients with depressive symptoms, and 30 HCs. The 53-channel functional near-infrared spectroscopy (fNIRS) was used to monitor the concentration of oxy-hemoglobin (Oxy-Hb) in the brain, whereas the participants performed the verbal fluency task, and the degree of depression was scored using the 17-item Hamilton Rating Scale for Depression (HAMD-17). Hierarchical regression models were conducted to analyze the association of fNIRS features with depressive symptom. The Oxy-Hb changes of the three groups were significantly different in Channels 25 (H=9.878, p=.007) and 43 (H=6.957, p=.031). Inter-group comparisons showed that the Oxy-Hb change of Channel 25 (located in the dorsolateral prefrontal cortex [DLPFC]) in OSA group was less than that in HC group (p=.006), and the Oxy-Hb change of Channel 43 (located in the right frontal polar region) in OSA group with depression was less than that in OSA group (p=.025). Spearman's test showed that there was a significant negative correlation between HAMD-17 scores and mean Oxy-Hb changes in Channel 43 (r=-.319, p<.05) in the OSA patients. Using hierarchical regression, Oxy-Hb changes in Channel 43 accounted for a significant proportion of the variation in outcome variables, even when accounting for other polysomnography features. Changes in the hemodynamic response of DLPFC may be a potential mechanism of executive dysfunction in OSA patients. And the right frontal polar region may be significant in assessing depressive symptoms in patients with OSA.

Study on the Effects of Acupuncture with the "Yizhi Tiaoshen" Acupoint Formula on Blood Oxygen Metabolism and Neural Function in Key Brain Regions of AD Rats.

Exploring the effects of acupuncture at the "Yizhi Tiaoshen" acupoint on blood oxygen metabolism and neurological function changes in the brain regions of AD model rats. The AD model was replicated by intraperitoneal injection of D-galactose combined with bilateral hippocampal CA1 injection of Okadaic acid (OA). Thirty rats with successfully replicated model were selected through Morris water maze experiment and randomly divided into model group, donepezil hydrochloride group, and acupuncture group, with 10 rats in each group. After treatment, fNIRs were used to detect changes in Oxy Hb, Deoxy Hb, and Total Hb in the cerebral cortex of rats in each group, in order to evaluate the neurological function changes in key brain areas. The escape latency of the donepezil hydrochloride group and the acupuncture group was shortened, the number of crossings through the original platform increased, and the duration of stay in the quadrant where the original platform was located was prolonged. Based on fNIRs detection, the main differential channels of blood oxygen metabolism in AD rats were identified as 2-2 and 8-7, corresponding to the prefrontal and parietal lobes, respectively. The concentrations of Oxy Hb and Total Hb were significantly increased in both treatment groups, while the concentration of Deoxy Hb was significantly decreased. Acupuncture with the "Yizhi Tiaoshen" acupoint formula and donepezil hydrochloride can improve the learning and memory function of AD rats, and its mechanism may be related to improving blood oxygen metabolism in the prefrontal and parietal regions and protecting neuronal function.

Taste dysfunction after COVID-19: Analysis with functional near-infrared spectroscopy.

&lt;br&gt;&lt;b&gt;Introduction:&lt;/b&gt; According to official data, COVID-19 emerged in China in December 2019 and has spread worldwide since then.&lt;/br&gt; &lt;br&gt;&lt;b&gt;Aim:&lt;/b&gt; The aim of this study was to investigate differences in functional near-infrared spectroscopy (fNIRS) recordings between convalescent COVID-19 patients and a healthy control group, which could help to clarify the pathomechanism of dysgeusia in COVID-19.&lt;/br&gt; &lt;br&gt;&lt;b&gt;Material and methods:&lt;/b&gt; The study included 16 participants, comprised of 8 convalescent COVID-19 patients and 8 healthy controls. All participants were examined with fNIRS. The amplitude of changes in oxyhemoglobin (oxyHb) concentration in the cerebral cortex was analyzed statistically (for the test and control groups after stimulation with a taste stimulus - citric acid solution).&lt;/br&gt; &lt;br&gt;&lt;b&gt;Results:&lt;/b&gt; The differences in the amplitude of changes in oxyHb concentration in the cerebral cortex were not statistically significant between the groups. Discussion: Using fNIRS, a strong stimulation of the visual cortex was discovered in response to the taste stimulus, consisting of large, repetitive changes in oxyHb concentration occurring in parallel with stimulation of areas of the taste cortex. This phenomenon has not, to our knowledge, been described previously in the scientific literature. The exact location of the primary taste cortex is controversial, but to date the occipital cortex has not been considered to be involved.&lt;/br&gt; &lt;br&gt;&lt;b&gt;Conclusions: No difference was observed in the dynamics of changes in oxyHb in the examined areas of the cerebral cortex between convalescent COVID-19 patients and healthy controls. However, the determination of the role of the occipital cortex in the perception of taste requires further research.&lt;/br&gt.

The abnormal brain activation pattern of adolescents with major depressive disorder based on working memory tasks: A fNIRS study

ObjectiveAlthough studies have confirmed that working memory (WM) is impaired among adults with major depressive disorder (MDD), generalizing these neurocognitive impairments to adolescents with MDD would be tenuous. Therefore, separate studies for adolescents with MDD are needed. Relatively little is known about the neural processes associated with WM dysfunction in adolescents with MDD. Thus, we examined whether adolescents with MDD have abnormal brain activation patterns compared to healthy controls (HC) during WM tasks and whether it was possible to distinguish adolescents with MDD and HC based on mean oxy-hemoglobin (Oxy-Hb) changes. MethodA total of 87 adolescents with MDD and 63 HC were recruited. Functional near-infrared spectroscopy (fNIRS) was performed to monitor the concentrations of Oxy-Hb in the frontotemporal lobe while participants performed three WM tasks in order to examine WM impairments in adolescents with depression. ResultsThe mean changes in Oxy-Hb concentrations in the left prefrontal cortex and right prefrontal cortex were higher among HC than among patients during the encoding and maintenance phase under each WM-load task. Machine learning was used to distinguish adolescents with MDD and HC based on Oxy-Hb changes, with a moderate area under the curve of 0.84. ConclusionsThis study revealed WM defects in adolescents with MDD compared to HC based on mean Oxy-Hb changes, which can be valuable for distinguishing adolescents with MDD from HC.

Acute hypoxia elicits prefrontal oxygenation asymmetry in young adults.

Cerebrovascular reactivity can be evaluated by prefrontal cortex (PFC) hemodynamic responses and oxygenation changes secondary to hypoxia using near-infrared spectroscopy (NIRS). However, whether there are hemispheric differences in these NIRS-determined PFC hemodynamic responses and oxygenation changes remains unknown. This study was performed to determine whether there are differences in the PFC hemodynamic responses and oxygenation changes secondary to hypoxia between the left and right frontal poles (FPL and FPR, respectively). Fifteen young men participated in the study. During conduction of an isocapnic hypoxia protocol with a 10-min hypoxic phase at partial pressure of end-tidal oxygen () of 45Torr, hemodynamic and oxygenation indices comprising oxygenated hemoglobin (oxy-Hb), deoxygenated Hb (deoxy-Hb), total Hb (total-Hb), and tissue oxygen saturation () over FPL and FPR were measured by NIRS. The heart rate (HR) was evaluated by electrocardiography. In response to hypoxia, the HR increased, oxy-Hb decreased, deoxy-Hb increased, total-Hb increased above baseline, and decreased. There was no difference in the change in total-Hb between FPL and FPR. However, there were greater changes in oxy-Hb, deoxy-Hb, and over FPL than over FPR, indicating that PFC oxygenation asymmetry occurs in response to hypoxia. Moreover, the change in total-Hb over FPL was associated with the increase in HR. NIRS-determined hemodynamic responses and oxygenation changes secondary to hypoxia might not simply reflect the direct effect of hypoxia on cerebral vessels. Although there is no hemispheric difference in the PFC hemodynamic responses to hypoxia as in total-Hb, PFC oxygenation asymmetry occurs in young adults.

A study on the functional near-infrared spectroscopy on impaired prefrontal activation and impulsivity during cognitive task in patients with major depressive disorder

BackgroundThis study aimed to examine the association between prefrontal activation during a verbal fluency task (VFT) and impulsivity among patients with major depressive disorder (MDD), using functional near-infrared spectroscopy (fNIRS). MethodsWe enrolled a total of 119 participants, 60 with MDD patients and 59 with healthy controls (HCs), aged 18 to 34 years. The Barratt Impulsiveness Scale–11 (BIS-11) was used to assess impulsivity after completing baseline demographic, clinical, and physical assessments. A VFT was used to examine prefrontal activation during cognitive executions while fNIRS was monitored. The changing values of oxygenated hemoglobin (oxy-Hb) and their associations with the BIS-11 score were analyzed. ResultsThe data analysis comprised 109 participants in total (54 MDD; 55 HCs). Spearman's correlation analysis of the MDD group showed a negative correlation between changes in oxy-Hb and BIS-11 values in the right prefrontal cortex, notably the right frontopolar cortex (FPC) and ventromedial prefrontal cortex (VMPFC). After adjusting for sex, age, years of education, and Hamilton Depression Rating Scale (HAMD), significance was maintained in the right FPC [ρ = −0.317, p = 0.027], and the right VMPFC [ρ = −0.327, p = 0.022]. Furthermore, multivariate linear regression suggested a significant association in the right prefrontal cortex with BIS-11 score [β = −1.904, SE = 0.799, p = 0.0214]. ConclusionsImpaired prefrontal activation during a verbal fluency task, led to higher impulsivity in patients with MDD.

Mild exercise improves executive function with increasing neural efficiency in the prefrontal cortex of older adults

This study examined whether a 3-month mild-exercise intervention could improve executive function in healthy middle-aged and older adults in a randomized control trial. Ultimately, a total of 81 middle-aged and older adults were randomly assigned to either an exercise group or a control group. The exercise group received 3 months of mild cycle exercise intervention (3 sessions/week, 30–50 min/session). The control group was asked to behave as usual for the intervention period. Before and after the intervention, participants did color-word matching Stroop tasks (CWST), and Stroop interference (SI)-related reaction time (RT) was assessed as an indicator of executive function. During the CWST, prefrontal activation was monitored using functional near-infrared spectroscopy (fNIRS). SI-related oxy-Hb changes and SI-related neural efficiency (NE) scores were assessed to examine the underlying neural mechanism of the exercise intervention. Although the mild-exercise intervention significantly decreased SI-related RT, there were no significant effects of exercise intervention on SI-related oxy-Hb changes or SI-related NE scores in prefrontal subregions. Lastly, changes in the effects of mild exercise on NE with advancing age were examined. The 81 participants were divided into two subgroups (younger-aged subgroup [YA], older-aged subgroup [OA], based on median age [68 years.]). Interestingly, SI-related RT significantly decreased, and SI-related NE scores in all ROIs of the prefrontal cortex significantly increased only in the OA subgroup. These results reveal that a long-term intervention of very light-intensity exercise has a positive effect on executive function especially in older adults, possibly by increasing neural efficiency in the prefrontal cortex.

Prefrontal oxygenation is quantified with time-resolved near-infrared spectroscopy: Effect of sex on baseline oxygenation and the response during exercise.

Using time-resolved near-infrared spectroscopy that enables quantitative analysis of optical properties and oxygenation in cerebral tissues and thereby subject-to-subject comparisons in the variables, this study examined the influence of sex on baseline optical properties and oxygenation in the prefrontal cortex (PFC) and the responses during cycling exercise. Absolute levels of oxygenated- and deoxygenated-hemoglobin concentration (Oxy-Hb and Deoxy-Hb) in bilateral PFC were measured at rest and during unilateral cycling at low- and moderate-intensity in young participants (8 women and 10 men). Unilateral cycling was utilized to evaluate no lateralization of the prefrontal oxygenation responses during exercise. Baseline optical properties of bilateral PFC, defined optical pathlength and reduced scattering coefficient, and their responses during cycling were not different between the sexes. Baseline absolute Oxy-Hb of bilateral PFC was significantly lower in women (37 ± 3 μM) than in men (47 ± 7 μM), whereas absolute Deoxy-Hb revealed no sex-related difference. The absolute Oxy-Hb levels in bilateral PFC during low- and moderate-intensity cycling were also lower in women. However, no sex difference was observed when using changes against the baseline levels to normalize baseline differences. No laterality-related differences were observed in the changes in prefrontal Oxy-Hb and Deoxy-Hb during unilateral cycling. Ascertaining no sex-related difference in optical properties of the PFC, the current findings suggest that baseline absolute level of oxygenation in the PFC is lower in women than in men, likely due to lower oxygen supply rather than higher oxygen utilization, and that prefrontal oxygenation responds similarly during exercise independently of sex.

Abnormal Prefrontal Brain Activation During a Verbal Fluency Task in Treatment-Resistant Depression Using Near-Infrared Spectroscopy.

The study investigated cognitive performance and brain function between treatment-resistant depression (TRD) and non- TRD patients to find potential neurobiological markers associated with refractoriness in depression patients. Fourteen TRD patients, 26 non-TRD patients and 23 healthy controls (HC) were included in the present study. The neural function of prefrontal cortex (PFC) and cognitive performance among the three group were examined using near-infrared spectroscopy (NIRS) during verbal fluency task (VFT). Both TRD and non-TRD groups exhibited significantly worse VFT performance and lower activation of oxygenated hemoglobin (oxy-Hb) changes in the bilateral dorsolateral PFC (DLPFC) compared to the HC group. Within the TRD and non-TRD groups, VFT performance was no significant difference, but activation of oxy-Hb changes in dorsomedial PFC (DMPFC) in TRD patients was significantly lower than non-TRD patients. In addition, activation of oxy-Hb changes in right DLPFC were negatively correlated with the severity of depressive symptoms in depression patients. Both TRD patients and non-TRD patients exhibited lower oxy-Hb activation in DLPFC. TRD patients exhibit lower oxy- Hb activation in DMPFC than non-TRD patients. fNIRS maybe a useful tool for predict depressive patients with or without treatment resistant.

Upper limb intelligent feedback robot training significantly activates the cerebral cortex and promotes the functional connectivity of the cerebral cortex in patients with stroke: A functional near-infrared spectroscopy study.

Upper limb intelligence robots are widely used to improve the upper limb function of patients with stroke, but the treatment mechanism is still not clear. In this study, functional near-infrared spectroscopy (fNIRS) was used to evaluate the concentration changes of oxygenated hemoglobin (oxy-Hb) and deoxyhemoglobin (deoxy-Hb) in different brain regions and functional connectivity (FC) of the cerebral cortex in patients with stroke. Twenty post-stroke patients with upper limb dysfunction were included in the study. They all received three different types of shoulder joint training, namely, active intelligent feedback robot training (ACT), upper limb suspension training (SUS), and passive intelligent feedback robot training (PAS). During the training, activation of the cerebral cortex was detected by fNIRS to obtain the concentration changes of hemoglobin and FC of the cerebral cortex. The fNIRS signals were recorded over eight ROIs: bilateral prefrontal cortices (PFC), bilateral primary motor cortices (M1), bilateral primary somatosensory cortices (S1), and bilateral premotor and supplementary motor cortices (PM). For easy comparison, we defined the right hemisphere as the ipsilesional hemisphere and flipped the lesional right hemisphere in the Nirspark. Compared with the other two groups, stronger cerebral cortex activation was observed during ACT. One-way repeated measures ANOVA revealed significant differences in mean oxy-Hb changes among conditions in the four ROIs: contralesional PFC [F(2, 48) = 6,798, p < 0.01], ipsilesional M1 [F(2, 48) = 6.733, p < 0.01], ipsilesional S1 [F(2, 48) = 4,392, p < 0.05], and ipsilesional PM [F(2, 48) = 3.658, p < 0.05]. Oxy-Hb responses in the contralesional PFC region were stronger during ACT than during SUS (p < 0.01) and PAS (p < 0.05). Cortical activation in the ipsilesional M1 was significantly greater during ACT than during SUS (p < 0.01) and PAS (p < 0.05). Oxy-Hb responses in the ipsilesional S1 (p < 0.05) and ipsilesional PM (p < 0.05) were significantly higher during ACT than during PAS, and there is no significant difference in mean deoxy-Hb changes among conditions. Compared with SUS, the FC increased during ACT, which was characterized by the enhanced function of the ipsilesional cortex (p < 0.05), and there was no significant difference in FC between the ACT and PAS. The study found that cortical activation during ACT was higher in the contralesional PFC, and ipsilesional M1 than during SUS, and showed tighter cortical FC between the cortices. The activation of the cerebral cortex of ACT was significantly higher than that of PAS, but there was no significant difference in FC. Our research helps to understand the difference in cerebral cortex activation between upper limb intelligent feedback robot rehabilitation and other rehabilitation training and provides an objective basis for the further application of upper limb intelligent feedback robots in the field of stroke rehabilitation.

Neural and behavioral alterations of a real-time interpersonal distance (IPD) development process in differing social status interactions.

BackgroundEvidence showed neural changes in interpersonal distance (IPD) interaction, and neural activities are affected by relationships (such as friends or strangers). Behavior studies proved that social status strongly affects IPD between two persons. However, how the differing social status impacts neural alterations in the IPD interactions remains unknown.ObjectivesThe teacher-student relationship is a typical representation of the difference in social status. The present study aims to investigate the IPD performance and brain processes underlying real-time differing social status during the development process from teacher-student interactions.Materials and methodsWe designed three within-subject experiments corresponding to the inclusion, control, and affection stages of IPD. Altogether, 38 valid healthy participants participated in three experiments with a teacher (differing social status condition, DS condition) and a peer student (peer social status condition, PS condition) separately. This study employed functional near-infrared spectroscopy (fNIRS) and modified real-time stop-distance paradigms to record IPD performance and neural processes.ResultsFor IPD performance, significantly larger IPD gaps were shown in the DS condition than in the PS condition, and IPD feedback affected IPD performance. For neural alterations, activated frontopolar area (FPA, BA10), dorsolateral prefrontal cortex (DLPFC, BA9/BA46), and Broca’s area (BA45) were observed across the IPD stages. Importantly, brain activation shifts with the development of IPD. In addition, results showed that differences in Oxy-Hb changes were located in the FPA (BA10), DLPFC (BA9/BA46), and Broca’s area (BA45) between the DS and PS conditions across IPD stages. Additionally, negative correlations were found between Oxy-Hb changes and IPD performance.ConclusionWe propose prefrontal cortex (PFC) and Broca’s area involvement in IPD interactions, initially focusing on evaluation and action periods, and later on IPD-evaluation processes after feedback. In addition, a difference in Oxy-Hb activities implies the complexity of relationships and social status in IPD interactions.

The impact of visual cross-modal conflict with semantic and nonsemantic distractors on working memory task: A functional near-infrared spectroscopy study.

Cross-modal conflicts arise when information from multisensory modalities is incongruent. Most previous studies investigating audiovisual cross-modal conflicts have focused on visual targets with auditory distractors, and only a few studies have focused on auditory targets with visual distractors. Moreover, no study has investigated the differences in the impact of visual cross-modal conflict with semantic and nonsemantic competition and its neural basis. This cross-sectional study aimed to characterize the impact of 2 types of visual cross-modal conflicts with semantic and nonsemantic distractors through a working memory task and associated brain activities. The participants were 33 healthy, right-handed, young male adults. The paced auditory serial addition test was performed under 3 conditions: no-distractor and 2 types of visual distractor conditions (nonsemantic and semantic distractor conditions). Symbols and numbers were used as nonsemantic and semantic distractors, respectively. The oxygenated hemoglobin (Oxy-Hb) concentration in the frontoparietal regions, bilateral ventrolateral prefrontal cortex (VLPFC), dorsolateral prefrontal cortex, and inferior parietal cortex (IPC) were measured during the task under each condition. The results showed significantly lower paced auditory serial addition test performances in both distractor conditions than in the no-distractor condition, but no significant difference between the 2 distractor conditions. For brain activity, a significantly increased Oxy-Hb concentration in the right VLPFC was only observed in the nonsemantic distractor condition (corrected P = .015; Cohen d = .46). The changes in Oxy-Hb in the bilateral IPC were positively correlated with changes in task performance for both types of visual cross-modal distractor conditions. Visual cross-modal conflict significantly impairs auditory working memory task performance, regardless of the presence of semantic or nonsemantic distractors. The right VLPFC may be a crucial region to inhibit visual nonsemantic information in cross-modal conflict situations, and bilateral IPC may be closely linked with the inhibition of visual cross-modal distractor, regardless of the presence of semantic or nonsemantic distractors.

Cognitive Function Mainly Shaped by Socioeconomic Status Rather Than Chronic Hypoxia in Adolescents at High Altitude.

Yu, Linyang, Jinqing Feng, Chen Zhou, Xiaohan Zhu, Xiaobin Lou, Jian Yang, Haiying Qi, and Jia Li. Cognitive function mainly shaped by socioeconomic status rather than chronic hypoxia in adolescents at high altitude. High Alt Med Biol. 23:223-231, 2022. Background: The study evaluated cognitive function in relation to the changes in brain tissue oxygenation in three groups of high school students from different socioeconomic regions including Tibetans in Jiuzhi and Lhasa (both at 3,600 m), and Han in Beijing (44 m). Methods: Jiuzhi, Lhasa, and Beijing Group included 21 Tibetans, 24 Tibetans, and 23 Han, respectively. Wechsler Intelligence Scale was used for cognitive evaluation. Functional near infrared spectroscopy was used to measure the changes of oxygenated hemoglobin (oxy-Hb) during the cognitive assessment. Gross domestic product (GDP) was used to indicate the socioeconomic status. Results: All the cognitive scores were significantly lower in the two high altitude groups compared with the Beijing Group (p < 0.001). The scores in Jiuzhi Group were significantly lower compared with the Lhasa Group (p < 0.001). The changes in oxy-Hb in channels 6 and 15 in both high-altitude groups were significantly greater compared with the Beijing Group (p < 0.05), without significant difference between the two high-altitude groups. GDP was significantly correlated with all the scores (p < 0.001), but not altitude. Conclusions: Cognitive impairment occurs in adolescents at high altitude, being severer in Jiuzhi Group compared with the Lhasa Group. The lower performance in both high-altitude groups require greater brain activity over-compensated by cerebral oxygen delivery as indicated by the changes in oxy-Hb. The cognitive scores were significantly correlated with GDP rather than altitude. Cognitive function in adolescents at high altitude is not limited by chronic hypoxia, but mainly shaped by socioeconomic determinants.

Effect of Audiovisual Cross-Modal Conflict during Working Memory Tasks: A Near-Infrared Spectroscopy Study.

Cognitive conflict effects are well characterized within unimodality. However, little is known about cross-modal conflicts and their neural bases. This study characterizes the two types of visual and auditory cross-modal conflicts through working memory tasks and brain activities. The participants consisted of 31 healthy, right-handed, young male adults. The Paced Auditory Serial Addition Test (PASAT) and the Paced Visual Serial Addition Test (PVSAT) were performed under distractor and no distractor conditions. Distractor conditions comprised two conditions in which either the PASAT or PVSAT was the target task, and the other was used as a distractor stimulus. Additionally, oxygenated hemoglobin (Oxy-Hb) concentration changes in the frontoparietal regions were measured during tasks. The results showed significantly lower PASAT performance under distractor conditions than under no distractor conditions, but not in the PVSAT. Oxy-Hb changes in the bilateral ventrolateral prefrontal cortex (VLPFC) and inferior parietal cortex (IPC) significantly increased in the PASAT with distractor compared with no distractor conditions, but not in the PVSAT. Furthermore, there were significant positive correlations between Δtask performance accuracy and ΔOxy-Hb in the bilateral IPC only in the PASAT. Visual cross-modal conflict significantly impairs auditory task performance, and bilateral VLPFC and IPC are key regions in inhibiting visual cross-modal distractors.

Cortical activation and functional connectivity during the verbal fluency task for adolescent-onset depression: A multi-channel NIRS study

ObjectiveDepression disorder is accompanied by cognitive impairments. However, there is limited research focused on cognitive impairments and their neurological mechanism in adolescents with depression. The purpose of the current study is to illustrate the differences in brain activity patterns between depressed adolescents and healthy controls (HCs). MethodA total of 72 adolescents with depression, as well as 74 HCs, were recruited. We utilized functional near-infrared spectroscopy (fNIRS) to monitor the concentrations of oxyhemoglobin (Oxy-Hb) in the brains of participants while they performed the verbal fluency task (VFT) to examine cognitive impairment in adolescents with depression. ResultsOur study demonstrated that adolescents with depression had significantly less cortical activation in the hemodynamic responses of Oxy-Hb at channels mainly located in the prefrontal cortex (PFC) than HCs during the 60-s task period (false discovery rate (FDR)-corrected p < 0.05). The mean channel-to-channel connectivity was 0.400 for HCs (SD = 0.149) and 0.303 (SD = 0.138) for adolescents with depression, and the HC group had a higher mean channel-to-channel connectivity strength than the depression group (t = −15.586, p < 0.001). For the patient group, we found significant negative correlations between HAMD scores and mean Oxy-Hb changes in Channel 38 (r = −0.33, p < 0.01), Channel 39 (r = −0.34, p < 0.01), Channel 41 (r = −0.25, p < 0.05), Channel 42 (r = −0.28, p < 0.05), and Channel 44 (r = −0.27, p < 0.05), and these channels were mainly located in areas with little difference between groups. ConclusionsOur study provides neurological evidence about the executive function (EF) in depressed adolescents. Adolescents with depression exhibited an abnormal activation pattern and decreased task-related functional connectivity compared to HCs. The changed Oxy-Hb concentration of PFC during VFT was not sensitive to depression symptoms.

Motor Imagery and Frontal Head Oxygenation: An fNIRS Study.

Motor imagery (MI) is a manifestation of mental movements, but it cannot be identified visually. Therefore, to a large extent, MI assessment has not yet been established. The present study aimed to investigate whether frontal oxy-Hb changes and cardiac autonomic nervous system activity during MI are associated with the psychometric scale assessment of MI and clarify the utility of each index in MI assessment. Thirty-one healthy men and women were included in this study, and Pocket NIRS Duo was used to assess frontal oxygenated hemoglobin levels during walking MI. Simultaneously, heart rate and sympathetic index (low and high frequency (LF/HF) during MI were evaluated using Chiryou Meijin, a heart rate frequency analyser. In addition, a psychometric scale evaluation was carried out in MC and VAS, and its correlation with oxy-Hb levels, heart rate (HR), and LF/HF was investigated. HRs and LF/HF during MI were significantly increased compared with those at rest. However, oxy-Hb levels during MI were not increased. There was a significant correlation between right oxy-Hb levels and mental chronometry (MC) during MI (r=-0.3, p<0.05). HR and LF/HF were not correlated with MC. VAS was not correlated with oxy-Hb levels, HR, or LF/HF. The results of this study confirm an association between MI performance and frontal oxy-Hb changes and that brain activity is not necessarily elevated during MI. HR were significantly increased but did not show any association with MC.

Clinical efficacy of motor imagery therapy based on fNIRs technology in rehabilitation of upper limb function after acute cerebral infarction.

Objective:To investigate the efficacy of motor imagery therapy (MIT) based on functional near-infrared spectroscopy (fNIRs) technology in rehabilitation of upper limb function after cerebral infarction, so as to provide guidance for clinical practice.Methods:A total of 84 patients with upper limb dysfunction after acute cerebral infarction admitted to Wuhan Puren Hospital from January 2020 to January 2021 were included in this study and randomly divided into two groups based on random number table method: experimental group and control group, with 42 cases in each group. Both groups were given active symptomatic treatment. The control group received conventional exercise rehabilitation, while the experimental group also received MIT based on fNIRs technology in addition to the treatment method adopted by the control group, lasting for eight weeks. The simplified Fugl-Meyer scale was utilized to evaluate the recovery of upper limb function, and the changes of Oxy-Hb and Deoxy-Hb concentrations in the frontal area of brain tissue were measured to evaluate the total effective rate of clinical rehabilitation.Results:At four and eight weeks of treatment, the Fugl-Meyer scores of the two groups were significantly higher than those before treatment (P<0.05), and those in experimental group were significantly higher than those in control group (P<0.05), with no significant difference before treatment (P>0.05). After treatment, Oxy-Hb concentration in the experimental group was higher than that in the control group (P<0.05), while Deoxy-Hb concentration was lower than that in the control group, with a statistical significance (P<0.05). The total effective rate of rehabilitation in the experimental group was 88.10%, which was significantly higher than 73.81% in the control group (P<0.05).Conclusion:Motor imagery therapy (MIT) Based on fNIRs technology has important clinical value in rehabilitation of upper limb function after cerebral infarction and is superior to conventional exercise rehabilitation alone, boasting a variety of effects, such as improving the curative effect, ameliorating blood oxygen in brain tissue, and promoting the rehabilitation of upper limb function of patients.

Frequent, Short Physical Activity Breaks Reduce Prefrontal Cortex Activation but Preserve Working Memory in Middle-Aged Adults: ABBaH Study.

Prolonged sitting is increasingly common and may possibly be unfavorable for cognitive function and mood. In this randomized crossover study, the effects of frequent, short physical activity breaks during prolonged sitting on cognitive task-related activation of the prefrontal cortex were investigated. The effects on working memory, psychological factors, and blood glucose were also examined, and whether arterial stiffness moderated prefrontal cortex activation. Thirteen subjects (mean age 50.5 years; eight men) underwent three 3-h sitting conditions, interrupted every 30-min by a different 3-min break on separate, randomized-ordered days: seated social interactions (SOCIAL), walking (WALK), or simple resistance activities (SRA). Arterial stiffness was assessed at baseline. Before and after each 3-h condition, psychological factors (stress, mood, sleepiness, and alertness) were assessed through questionnaires and functional near-infrared spectroscopy (fNIRS) was used to measure changes in prefrontal oxygenated hemoglobin (Oxy-Hb), indicative of cortical activation, while performing working memory tasks [1- (baseline), 2-, and 3-back]. Blood glucose levels were continuously measured throughout the conditions. Results revealed no significant changes in Oxy-Hb during the 2-back compared with the 1-back test in any condition, and no time-by-condition interactions. During the 3-back test, there was a significant decrease in Oxy-Hb compared with the 1-back after the WALK condition in the right prefrontal cortex, but there were no time-by-condition interactions, although 3-back reaction time improved only in the WALK condition. Mood and alertness improved after the WALK condition, which was significantly different from the SOCIAL condition. Arterial stiffness moderated the effects, such that changes in Oxy-Hb were significantly different between WALK and SOCIAL conditions only among those with low arterial stiffness. Blood glucose during the interventions did not differ between conditions. Thus, breaking up prolonged sitting with frequent, short physical activity breaks may reduce right prefrontal cortex activation, with improvements in some aspects of working memory, mood, and alertness.Clinical Trial Registration:www.ClinicalTrials.gov, identifier NCT04137211.

Unchanged Cognitive Performance and Concurrent Prefrontal Blood Oxygenation After Accelerated Intermittent Theta-Burst Stimulation in Depression: A Sham-Controlled Study.

Aim: Intermittent theta-burst stimulation (iTBS) delivered over the dorsomedial prefrontal cortex (DMPFC) has shown promise as a treatment for anhedonia and amotivation in patients with depression. Here, we investigated whether this protocol modulates cognitive performance and concurrent prefrontal blood oxygenation. We also examined whether depressed patients exhibit cognitive dysfunction and prefrontal hypoactivity at baseline compared to healthy controls.Methods: This sham-controlled study comprises 52 patients randomized to either active or sham accelerated iTBS over the DMPFC (applied twice daily) for 10 consecutive treatment days, and 55 healthy controls. Cognitive performance was assessed at baseline and once again 4 weeks later using a cognitive test battery targeting attention, inhibitory control, and numerical, verbal, and visual working memory. Concurrent prefrontal oxygenated hemoglobin (oxy-Hb) was captured with functional near-infrared spectroscopy.Results: Active iTBS over DMPFC did not affect cognitive performance or concurrent oxy-Hb change compared to sham iTBS in patients with depression. Compared to controls, patients at baseline showed impaired performance in the Trail Making Test, the Rey Auditory Verbal Learning Test, the Animal Naming Test, and the Digit Symbol Substitution Test, however no difference in prefrontal oxy-Hb was observed.Conclusion: Patients with treatment-resistant depression displayed cognitive deficits, however without prefrontal hypoactivity, compared to healthy controls at baseline. iTBS treatment did not alter cognitive performance, nor concurrent prefrontal blood oxygenation, in patients. Taken together, iTBS can likely be considered a cognitively safe treatment option in this sample of patients.

β-Lactolin, a Whey-Derived Gly-Thr-Trp-Tyr Lactopeptide, Promotes Cerebral Blood Flow During Cognitive Tasks: A Randomized Controlled Trial

ObjectivesDue to the rapid aging of society, the prevention of age-related cognitive decline and dementia has gained increasing attention. Recent epidemiological investigations have shown that the consumption of dairy products reduces the risk of dementia in older adults. β-lactolin, a whey-derived Gly-Thr-Trp-Tyr lactopeptide, activates the dopaminergic system, improves memory impairment, and prevents Alzheimer’s pathologies in a rodent model. We have demonstrated that β-lactolin supplementation improves memory retrieval and selective attention in randomized trials. On the other hand, the mechanisms underlying the effects of β-lactolin on human brain activity have not been investigated. MethodsWe examined the effects of β-lactolin on cerebral blood flow (CBF) using near-infrared spectroscopy (NIRS) in a placebo-controlled randomized double-blind study. Fifty healthy participants (45–60 years old) were randomly allocated to the β-lactolin and placebo groups and supplemented for 6 weeks. At 0 and 6 weeks of the intervention, oxyhemoglobin (Hb) was measured using 34-channel (CH) NIRS during the working memory tasks. ResultsThe changes in oxy-Hb in CH23 located at the left dorsolateral prefrontal cortex (DLPFC) during the spatial working memory task showed a higher statistical significance (false discovery rate (q) = 0.045) in the β-lactolin than in the placebo group. The CBF changes in CH23 were correlated with the reaction time for the working memory task. A recent trial using a 2-CH NIRS also showed a significant CBF increase in the DLPFC area after β-lactolin supplementation. Conclusionsβ-lactolin supplementation increases CBF in the DLPFC area, which contributes to improved cognitive functions. Funding SourcesCurrent study was funded by Kirin Holdings Co. Ltd.