Spatial registration of multichannel multi-subject fNIRS data to MNI space without MRI

Enhancing Neural Activation in Older Adults: Action Observation-Primed Swallowing Imagery Reveals Age-Related Connectivity Patterns

Aging-related swallowing decline, known as presbyphagia, significantly increases the risk of dysphagia and aspiration pneumonia in older adults. Enhancing cortical activation and functional connectivity through non-invasive methods is crucial for improving swallowing function. This study investigates the use of action observation (AO) as a priming method to enhance motor imagery (MI) for promoting swallowing-related cortical activity. A total of 22 healthy young adults and 20 healthy older adults were recruited. Participants completed two swallowing imagery tasks: an 8-minute AO-primed task and an 8-minute unprimed task. Functional near-infrared spectroscopy was used to measure changes in oxyhemoglobin concentration as an indicator of cortical activation. Corrected imaginary phase-locking values (ciPLVs) were calculated to estimate functional connectivity between brain regions. In young adults, AO-primed tasks showed widespread bilateral activation in the sensorimotor cortex, supplementary motor area (SMA), and visual cortex, while unprimed tasks activated only the right inferior frontal gyrus. In older adults, AO-primed tasks activated the left sensorimotor cortex, SMA, and visual cortex, but unprimed tasks did not result in any significant cortical activation. Despite both age groups recruiting similar cortical networks, older adults exhibited reduced connectivity, particularly in the prefrontal-sensorimotor pathways during AO-primed tasks. AO-priming enhances cortical activation and connectivity in both young and older adults during swallowing imagery tasks. However, older adults demonstrate weaker neural connectivity, suggesting that age-related cortical decline may limit the effectiveness of such interventions. AO-primed MI may serve as a promising strategy for improving swallowing function in older populations.

Functional characteristics of the frontal cortex during the verbal fluency task in subthreshold depression: A fNIRS study

BACKGROUND

Subthreshold depression (SD), a recognized prodromal stage and major risk factor for major depressive disorder (MDD). Dysfunction of the frontal lobe is associated with the emergence and progression of depression. This study aims to systematically examine the functional characteristics of the frontal cortex in SD, including activation, functional connectivity (FC), and network topology properties.

METHODS

Using functional near-infrared spectroscopy (fNIRS) during verbal fluency tasks (VFT), the relative concentration of oxyhaemoglobin in the frontal cortex was measured in 70 female subjects with SD and 73 matched healthy controls.

RESULTS

The SD subjects demonstrated reduced dorsolateral prefrontal cortex activation. FC analyses indicated weakened frontal cortex connectivity with adjacent regions and disrupted interhemispheric connectivity, alongside enhanced long-distance and edge frontal connectivity. Graph theory revealed functional network abnormalities of the frontal cortex in SD: decreased overall clustering coefficient (Cp), left-hemisphere Cp with increased global efficiency, and diminished right-hemisphere assortativity. Crucially, overall frontal Cp correlated with depressive symptom severity and showed predictive value for SD.

CONCLUSION

During the VFT, SD subjects exhibited reduced frontal cortex activation, altered FC patterns, and functional network abnormalities. This study was the first to report that the Cp of the overall frontal cortex has the potential for prediction in SD. Our findings elucidate SD neuropathology and establish a foundation for early MDD diagnosis.

Language processing in emergencies recruits both language and default mode networks

Effective language processing in emergencies is crucial for professionals, including firefighters, soldiers, and doctors. Substantial research has been undertaken on language processing in silence, with several studies indicating the impact of noise on language processing in non-emergencies. However, it remains unclear about the neural mechanisms involved in language processing during emergencies, especially the role of the language network (LN) and the default mode network (DMN) in such contexts. In this study, we adopted functional near-infrared spectroscopy (fNIRS) to investigate brain activities of 60 participants who were performing language processing tasks in simulated high-emergency and low-emergency scenarios. Compared to the resting state, the reading task demonstrated reduced activation in bilateral superior and middle frontal gyri (SFG/MFG), components of the DMN, alongside enhanced activation in Broca's area, left temporal lobe and left inferior parietal lobule (IPL) - key LN regions. Furthermore, the activity of the left MFG was positively correlated with the level of stress experienced by participants during the task. Additionally, a positive correlation was identified between language processing performance and activation of the left MFG, exclusively in the participants exposed to high-emergency scenarios. These results support the view that language processing during emergency relies on both the LN and DMN. The current study deepens our understanding of the neural mechanisms that underlie language processing in complex, real-life emergency scenarios.

Test-retest reliability of functional near infrared spectroscopy during tasks of inhibitory control and working memory

Functional near-infrared spectroscopy (fNIRS) has become a well-established tool for neuroscience research and been suggested as a potential biomarker during clinical assessment in individuals with mental disorders. Biomarker need to be objective indications of biological processes which can be measured accurately and reproducibly. Despite various applications in clinical research, test-retest reliability of the fNIRS signal has not yet been evaluated sufficiently. To assess reliability of the fNIRS signal during tasks of executive functions, a group of 34 healthy subjects (13 male, 21 female) were tested twice for inhibitory control and working memory. On a group level results show a specific activation pattern throughout the two sessions, reflecting a task-related frontal network associated with the assessed cognitive functions. On the individual level the retest reliability of the activation patterns were considerably lower and differed strongly between participants. In conclusion, the interpretation of fNIRS signal on a single subject level is partially hampered by its low reliability. More studies are needed to optimize the retest reliability of fNIRS and to be applied on a routine basis in developmental research.

Simultaneous monitoring of the human brain, spinal cord, and cauda equina activity for movement control: An fNIRS approach

Brain‒spinal cord‒cauda equina interactions are essential for controlling lower body movement. However, current monitoring approaches for spinal and caudal activity are limited to use without body movement and to processing via batches of data. Here, we present a novel optical method based on functional near-infrared spectroscopy that enables simultaneous tracking of human brain-spinal cord-cauda equina hemodynamics during body movement. We first developed a support frame for positioning optical emitters and receivers along the spinal canal to maximize spatial resolution and identify the optimal distance between them. We tested the methodology at this optimal emitter-detector distance by assessing the spatiotemporal activation of the motor clusters associated with human ankle extension-flexion movement in the brain, spinal cord, and cauda equina. These brain and spinal clusters are shown to be functionally connected and comparable to those identified by invasive methods during surgical operations. These findings suggest that hemodynamic responses reflect synchronous neural activity in the human brain-spinal cord-cauda equina system for hindlimb movement control.

Multi-task exercise increases delta power in non-rapid eye movement sleep among older female adults: A randomized crossover trial

Delta power in electroencephalography during sleep has been used as a more quantitative approach to determine sleep depth and quality. Despite the positive effects of both exercise and cognitive activity on delta power during sleep, limited information is available regarding the effects of multi-task exercise, which combines these two activities. Therefore, this study aimed to investigate the impact of multi-task exercise on delta power during sleep. Fifteen older female adults participated in both multi-task and single-task exercises at low and moderate-to-vigorous intensities for 30 min each. Sleep architecture was recorded using polysomnography to compare the amount of delta power during sleep. Additionally, cortical hemodynamic changes in the prefrontal cortex were monitored using functional near-infrared spectroscopy before and after each exercise session. Low-intensity multi-task exercise increased cortical activation in the right and left ventrolateral prefrontal cortex and frontopolar area, which positively correlated with the increase in delta power. This study provides the first experimental evidence that low-intensity multi-task exercise enhances cortical activation in the prefrontal cortex of older female adults, leading to an increase in delta power during sleep. It also suggests that low-intensity multi-task exercise may be a more useful intervention for improving sleep quality in older adults.

Task-switching and frontal cortex functioning across adulthood: An fNIRS study

Switching between tasks is slower and more error-prone than performing a single task. While studies have compared task-switching and associated neural processing between younger and older adults, knowledge of age-related differences in components of task-switching across adulthood, and associated neural mechanisms, remains elusive. In this study, these age differences were investigated using functional near-infrared spectroscopy (fNIRS). A sample of 132 adults aged 18-79 undertook a variant of the Trail Making Test and a task-switching paradigm. Hemodynamic changes in the bilateral frontal cortex during the task-switching paradigm were measured using a 48-channel fNIRS device. Behavioral results showed that age showed a negative linear relationship with time taken to task-switch and a negative quadratic relationship with success in task-switching. In addition, fNIRS results showed that age had a positive linear relationship with activation in the left posterolateral frontal cortex across trial conditions. Among older adults, who had slower and less accurate switch performance than younger adults, greater left posterolateral frontal activation was associated with faster and more accurate switch performance. Therefore, different aspects of task-switching performance exhibit varying patterns of age-related differences across adulthood. Increased engagement of the left posterolateral frontal cortex, which plays a specific role in reconfiguring and implementing relevant task rules, may help older adults compensate for declined switch performance.

Prefrontal executive function enhanced by prior acute inhalation of low-dose hypoxic gas: Modulation via cardiac vagal activity

Today, diverse psychophysiological stresses, such as severe time constraints and busy lifestyles, contribute to cardiac parasympathetic dysfunction, potentially leading to mental health issues and declines in critical executive functions. It is essential to develop accessible methods of enhancing cardiac vagal activity (CVA) to mitigate these adverse effects. We previously demonstrated that inhaling low-dose hypoxic gas (FIO₂: 13.5 %) for 10 min acts as a hormetic stressor, inducing a supercompensation effect in CVA post-hypoxia. Since CVA is a key mediator of brain-heart communication in that it influences executive functions by interacting with the left dorsolateral prefrontal cortex (L-DLPFC), increasing CVA may enhance cognitive ability. We hypothesized that acute low-dose hypoxia leads to enhanced executive function via CVA modulation. Twenty-six individuals participated in both normobaric hypoxia (NH; FIO₂: 13.5 %) and normoxia (NN; ambient air) conditions. CVA, measured through heart rate variability, was analyzed three times: pre-hypoxia/normoxia, hypoxia/normoxia, and post-hypoxia/normoxia. Executive function was assessed using the Stroop task before and after exposure, and prefrontal cortex activity during the task was monitored using multichannel functional near-infrared spectroscopy. A supercompensation of CVA occurred concomitantly with a reduction in heart rate following hypoxic gas inhalation. Stroop performance improved with increased task-related activation of the L-DLPFC in the NH condition. Causal mediation analysis revealed that the post-hypoxia enhancement of CVA mediated improvements in Stroop performance and increased L-DLPFC activation. These findings strongly support our hypothesis that the enhancement of CVA following hormetic hypoxic stress contributes to improved executive function, broadening the scope of neurocognitive approaches for effectively enhancing executive function.

Food properties modulate activities in posterior parietal and visual cortex during chewing

Cross-modal interactions between sensory modalities may be necessary for recognition of chewing food by the invisible oral cavity to avoid damaging the tongue and/or oral mucosa. The present study used functional near-infrared spectroscopy to investigate whether the food properties hardness and size influence activities in the posterior parietal cortex and visual cortex during chewing performance in healthy individuals. It was found that an increase in food hardness enhanced both posterior parietal cortex and visual cortex activities, while an increase in food size enhanced activities in the same regions. These findings suggested a quantitative relationship of oral food properties with activities in the brain regions responsible for object recognition and visuospatial processing. It is thus concluded that heightened neural activities in the posterior parietal cortex and visual area reflect an increased demand for cross-modal representation of food properties related to chewing.

Gratitude enhances widespread dynamic cooperation and inter-brain synchronization in females

From both social and life perspectives, gratitude is essential for managing social relationships and fostering cooperation. This study investigated the dynamic influence of gratitude on two modalities of cooperative interactions and the associated interpersonal dynamic neural mechanism by integrating a dyadic ecological paradigm with functional near-infrared spectroscopy). Several critical findings emerged: the gratitude group exhibited better cooperative behaviors compared to the joy and neutral groups in both the Prisoner's Dilemma Game (PDG) and the Button-press Game (BPG). The dynamic cooperative behaviors further elucidated that gratitude dynamically facilitates cooperation by boosting inclusivity towards the benefactor's slight defect in the PDG and heightening action coordination in the BPG. Accordingly, higher inter-brain synchronization (IBS) was predominantly observed in the left and right middle frontal gyrus and the right sensorimotor cortex in the gratitude, compared to the joy and neutral groups. Moreover, the gratitude group exhibited increased IBS over time (across blocks) in the left and right middle frontal gyrus and the right superior temporal gyrus. These findings substantiate that gratitude facilitates widespread social cooperation and progressively enhances IBS among individuals. This work advances our understanding of gratitude-induced large-scale cooperative behaviors in societies.

Mood symptoms, cognitive function, and changes of brain hemodynamics in patients with COVID-19: A functional near-infrared spectroscopy study

BACKGROUND

Many patients with coronavirus disease 2019 (COVID-19) may experience emotional issues and cognitive impairment. However, it remains unclear whether the brain mediates the impact of COVID-19 on the emergence of psychopathological symptoms. It remains unclear whether anxiety and depression are caused by stressors or viral infection.

AIM

To use functional near-infrared spectroscopy (fNIRS) to detect cortical hemodynamic changes in patients with COVID-19 and their relationship with mental symptoms (mainly depression and anxiety), to investigate whether COVID-19 causes these changes by affecting brain function.

METHODS

A total of 58 subjects, comprising 29 patients with first acute COVID-19 infection and 29 healthy controls without COVID-19 infection and without anxiety or depression were recruited. Then cortical activation during the performance of the verbal fluency test (VFT) and brain connectivity during the resting state (rs) were evaluated by 53-channel fNIRS. For the COVID-19-infected group, Patient Health Questionnaire-9 (PHQ-9) and General Anxiety Disorder-7 (GAD-7) were used to assess the emotional state before fNIRS measures.

RESULTS

For the rs, compared to the uninfected group, the infected group exhibited lower rs functional connectivity (FC) in the dorsolateral prefrontal cortex (DLPFC), which was correlated with both the PHQ score and GAD score. During the VFT, the infected group exhibited significantly lower cortical activation than the uninfected group in both Broca-left and Broca-right. Besides, the integral value in the DLPFC-L showed a significant negative correlation with the PHQ-9 score during the VFT in the infected group.

CONCLUSION

There were significant differences in the bilateral Broca area and DLPFC between the COVID-19-infected and uninfected groups, which may be the reason why COVID-19 infection impairs cognitive function and language function and leads to psychiatric symptoms. In addition, the rsFC in patients with COVID-19 was positively correlated with the severity of depression and anxiety, which may be related to the fact that the mental symptoms of patients with COVID-19 are characterized by depression and anxiety, rather than depression or anxiety alone. Our study provides evidence that the psychological and emotional issues caused by COVID-19 are not only due to external social factors but also involve more direct brain neural mechanisms and abnormal neural circuits, which also provide insights into the future treatment and prognosis of individuals with COVID-19.

The neural characteristics influencing literacy outcome in children with cochlear implants

Early hearing intervention in children with congenital hearing loss is critical for improving auditory development, speech recognition and both expressive and receptive language, which translates into better educational outcomes and quality of life. In children receiving hearing aids or cochlear implants, both adaptive and potentially maladaptive neural reorganization can mitigate higher-level functions that impact reading. The focus of the present study was to dissect the neural underpinnings of the reading networks in children with cochlear implants and assess how these networks mediate the reading ability in children with cochlear implants. Cortical activity was obtained using naturalistic stimuli from 75 children (50 cochlear implant recipients, aged 7-17, and 25 age-matched children with typical hearing) using functional near-infrared spectroscopy. Assessment of basic reading skill was completed using the Reading Inventory and Scholastic Evaluation. We computed directed functional connectivity of the haemodynamic activity in reading-associated anterior and posterior brain regions using the time-frequency causality estimation method known as temporal partial directed coherence. The influence of the cochlear implant-related clinical measures on reading outcome and the extent to which neural connectivity mediated these effects were examined using structural equation modelling. Our findings reveal that the timing of intervention (e.g. age of first cochlear implants, age of first hearing aid) in children with cochlear implants significantly influenced their reading ability. Furthermore, reading-related processes (word recognition and decoding, vocabulary, morphology and sentence processing) were substantially mediated by the directed functional connectivity within reading-related neural circuits. Notably, the impact of these effects differed across various reading skills. Hearing age, defined as the age at which a participant received adequate access to sound, and age of initial implantation emerged as robust predictors of reading proficiency. The current study is one of the first to identify the influence of neural characteristics on reading outcomes for children with cochlear implants. The findings emphasize the importance of the duration of deafness and early intervention for enhancing outcomes and strengthening neural network connections. However, the neural evidence further suggested that such positive influences cannot fully offset the detrimental impact of early auditory deprivation. Consequently, additional, perhaps more specialized, interventions might be necessary to maximize the benefits of early prosthetic hearing intervention.

Positive resonance: Successful interpersonal emotion regulation facilitated relationship closeness by enhanced inter-brain synchronization

Interpersonal emotion regulation (IER) refers to the dynamic process where a regulator employs specific strategies to alleviate a target's distress. It remains unclear whether successful IER could facilitate interpersonal relationship closeness (IRC). The present study aimed to explore whether successful IER, based on two typical strategies-cognitive reappraisal (CR) and expressive suppression (ES)-for down-regulating the target's negative emotions, could enhance IRC among friend dyads, and to identify the underlying neural correlates of this process using functional near-infrared spectroscopy system. Seventy-four female dyads (friends) were randomly assigned to one of two strategy groups (CR vs. ES), with one participant as the target and the other as the regulator. Our findings revealed that both strategies have down-regulated the target's negative emotions, however, CR strategy was associated with more successful IER outcomes (more improvement of the targets' negative emotions; higher IRC) than ES strategy. IER recruited the enhanced interpersonal brain synchronization (IBS) of the prefrontal and temporal areas among friend dyads. CR strategy recruited higher IBS of the above-mentioned brain networks than ES strategy in down-regulating the target's sadness, and the reversed IBS pattern was found in down-regulating the target's anger, inferring that CR was more successive in IER of sadness, and ES was more effective in IER of anger. The increased IBS pattern of these brain regions played a mediational role between the effectiveness of down-regulating targets' negative emotions and the increment of IRC. Our findings revealed a neural coupling mechanism through which successful IER fostered supportive social bonds.

Integrating behavioral and neurophysiological insights: High trait anxiety enhances observational fear learning

Observational fear learning delineates the process by which individuals learn about potential threats through observing others' reactions. Prior research indicates that individuals with high trait anxiety (HTA) manifest pronounced fear responses in direct fear learning scenarios. However, the specific influence of trait anxiety on observational fear learning remains insufficiently explored. This study aimed to fill this gap by examining 64 university students, divided equally between those with HTA and low trait anxiety (LTA), selected from an initial pool of 483 participants. Participants were subjected to observational fear learning tasks, and their behavioral responses, physiological reactions, and brain activations were recorded. Results demonstrated that HTA participants exhibited differentiated skin conductance responses to threat and safety stimuli during the observational fear acquisition phase, notwithstanding prior assurances against shock delivery. Furthermore, during the direct test phase, HTA participants reported significantly elevated fear and shock expectancy ratings for both types of stimuli, in contrast to their LTA counterparts. Neuroimaging data, derived via functional near-infrared spectroscopy (fNIRS) revealed heightened medial prefrontal cortex activation in HTA participants when directly facing threats. This study systematically explores the influence of high trait anxiety on observational fear learning, uncovering that HTA individuals exhibit excessive fear responses. These findings highlight the critical role of trait anxiety as a significant risk factor in the development of anxiety disorders.

Examining emotion reactivity to politically polarizing media in a randomized controlled trial of mindfulness training versus active coping training

Emotional appraisals of political stimuli (e.g., videos) have been shown to drive shared neural encoding, which correspond to shared, yet divisive, interpretations of such stimuli. However, mindfulness practice may entrain a form of emotion regulation that de-automatizes social biases, possibly through alteration of such neural mechanisms. The present study combined a naturalistic neuroimaging paradigm and a randomized controlled trial to examine the effects of short-term mindfulness training (MT) (n = 35) vs structurally equivalent Cognitive Reappraisal training (CT) (n = 37) on politically-situated emotions while evaluating the mechanistic role of prefrontal cortical neural synchrony. Participants underwent functional near-infrared spectroscopy (fNIRS) recording while viewing inflammatory partisan news clips and continuously rating their momentary discrete emotions. MT participants were more likely to respond with extreme levels of anger (odds ratio = 0.12, p < 0.001) and disgust (odds ratio = 0.08, p < 0.001) relative to CT participants. Neural synchrony-based analyses suggested that participants with extreme emotion reactions exhibited greater prefrontal cortical neural synchrony, but that this pattern was less prominent in participants receiving MT relative to CT (CT > MT; channel 1 ISC = 0.040, p = 0.030).

A free association semantic task for fNIRS-based perinatal depression assessment

Perinatal depression (PD) is a highly prevalent psychological disorder that has a detrimental effect on infant and maternal physical and mental health, but effective and objective assessment of PD is still insufficient. In recent years, the functional near-infrared spectroscopy (fNIRS) has been acknowledged as an effective non-invasive tool for clinical assessment of depression. This study proposed a free association semantic task (FAST) paradigm for fNIRS-based assessment of PD. To better address the emotion characteristics of PD, the participants are required to generate a dynamic concept chain based on positive, negative or neutral seed words, while 48-channel fNIRS recordings over frontal and bilateral temporal regions. Results from twenty-two late-pregnant women revealed that, the oxyhemoglobin (oxy-Hb) changes during the FAST with the positive and negative seed words over the frontal region were correlated with PD severity, which was different from the correlation patterns in the FAST with neutral seed word and the classical verbal fluency test (VFT). Furthermore, distinct correlation patterns were also observed in the FAST with the positive and negative seed words, manifested in fNIRS channels corresponding to the right dorsolateral prefrontal cortex (DLPFC) and right inferior frontal gyrus (IFG), respectively. Moreover, regression analyses showed that the FAST with positive and negative seed words can well explain the severity of PD. Our findings suggest the proposed FAST paradigm as a promising approach for PD assessment.

A computational and multi-brain signature for aberrant social coordination in schizophrenia

Social functioning impairment is a core symptom of schizophrenia (SCZ). Yet, the computational and neural mechanisms of social coordination in SCZ under real-time and naturalistic settings are poorly understood. Here, we instructed patients with SCZ to coordinate with a healthy control (HC) in a joint finger-tapping task, during which their brain activity was measured by functional near-infrared spectroscopy simultaneously. The results showed that patients with SCZ exhibited poor rhythm control ability and unstable tapping behaviour, which weakened their interpersonal synchronization when coordinating with HCs. Moreover, the dynamical systems modeling revealed disrupted between-participant coupling when SCZ patients coordinated with HCs. Importantly, increased inter-brain synchronization was identified within SCZ-HC dyads, which positively correlated with behavioural synchronization and successfully predicted dimensions of psychopathology. Our study suggests that SCZ individuals may require stronger interpersonal neural alignment to support their deficient coordination performance. This hyperalignment may be relevant for developing inter-personalized treatment strategies.

Synchronization of brain activity associated with eye contact: comparison of face-to-face and online communication

Online meetings have become increasingly prevalent, especially during the coronavirus disease 2019 pandemic. Although they offer convenience and effectiveness in various contexts, there is a pertinent question about whether they truly replicate the richness of in-person communication. This study delves into the distinctions between online and face-to-face interactions, with a particular focus on the synchronization of brain activity. Previous research has indicated a connection between synchronization and the quality of communication. Therefore, our hypothesis posits that face-to-face interactions lead to greater brain synchronization compared to online interactions, which often lack certain social cues. To investigate this, we conducted a study using functional near-infrared spectroscopy hyperscanning during an eye-contact task involving 28 male participants organized into 14 pairs. We assessed brain signal synchronization using wavelet coherence analysis. After comparing face-to-face and online conditions, our findings revealed significantly higher synchronization in face-to-face scenarios, particularly within the right temporoparietal region. These results align with the outcomes of other hyperscanning studies and suggest that face-to-face communication elicits a higher level of brain synchronization compared with online communication. In the future, this approach holds promise for evaluating the effectiveness of online meeting tools in achieving a more authentic virtual communication experience.

Effects of Physical Exercise Breaks on Executive Function in a Simulated Classroom Setting: Uncovering a Window into the Brain

Acknowledging the detrimental effects of prolonged sitting, this study examined the effects of an acute exercise break during prolonged sitting on executive function, cortical hemodynamics, and microvascular status. In this randomized crossover study, 71 college students completed three conditions: (i) uninterrupted sitting (SIT); (ii) SIT with a 15 min moderate-intensity cycling break (MIC); and (iii) SIT with a 15 min vigorous-intensity cycling break (VIC). Behavioral outcomes, retinal vessel diameters (central retinal artery equivalents [CRAE], retinal vein equivalents [CRVE], arteriovenous ratio [AVR]), cortical activation, and effective connectivity were evaluated. Linear mixed models identified significant positive effects of exercise conditions on behavioral reaction time (RT), error rate, and inverse efficiency score (β = -2.62, -0.19, -3.04: ps < 0.05). MIC and VIC conditions produced pre-to-post-intervention increases in CRAE and CRVE (β = 4.46, 6.34), frontal activation, and resting-state and task-state causal density (β = 0.37, 0.06) (ps < 0.05) compared to SIT; VIC was more beneficial for executive function and neurobiological parameters. The effect of AVR on average RT was mediated through task-based causal density (indirect effect: -0.82). Acutely interrupting prolonged sitting improves executive function, microvascular status, and cortical activation and connectivity, with causal density mediating the microvascular-executive function link.

Syntactic development and its interplay with word processing and working memory in preschoolers' brain: An fNIRS longitudinal study

Understanding how children acquire syntactic structures from a limited set of grammatical rules and use them creatively to convey meaning has been a longstanding interest for scientific communities. Previous studies on syntactic development have revealed its close correlation with the development of vocabulary and working memory. Our study sought to elucidate how the relations between syntactic processing, word processing, and working memory were instantiated in the brain, and how earlier neural patterns might predict language abilities one year later. We employed functional near-infrared spectroscopy to examine among preschool children (N=50, Mage=61.5 months) the neural activation associated with processing sentences of varying syntactic complexities, as well as tasks assessing word comprehension and working memory. The results revealed greater brain activation in the left inferior frontal gyrus (IFG) for syntactically complex as compared to simple sentences, and the activation magnitude was correlated with working memory. There was also a link between neural activity for sentence comprehension and word comprehension in bilateral superior temporal regions (STG). Moreover, the inter-regional and inter-hemispheric connectivity of IFG and STG/MTG could successfully predict children's future language comprehension one year later. The findings provide new insights into how the brain supports syntactic development and its interplay with word processing and working memory.

Pilot Study of Cerebral Hemodynamics in Depressive Patient Under Electroconvulsive Therapy

Background

Major depressive disorder (MDD) poses a significant treatment challenge, with some patients unresponsive to conventional therapies. Electroconvulsive therapy (ECT) can be effective but its mechanisms are not fully understood. This study employs functional Near-Infrared Spectroscopy (fNIRS) to explore the neurobiological changes induced by ECT in A MDD patient, aiming to shed light on its therapeutic effects.

Purpose

This study employs fNIRS to assess differences between MDD patient and controls, and examines changes in cerebral hemodynamics and brain network nodes post-ECT to elucidate treatment mechanisms.

Methods

26 age and gender-matched controls and one MDD male patient underwent fNIRS during a verbal fluency task. The patient received ECT, with dynamic evaluation of beta, integral, and centroid values in regions of interest (ROIs) post-treatment. Resting-state fNIRS and functional connectivity assessments were also conducted post-ECT.

Results

MDD patient exhibited significantly lower hemodynamic metrics and functional connectivity compared to controls at baseline. Post-ECT, dynamic changes in these metrics were observed, trending towards normalization and showing no significant differences from controls.

Conclusion

ECT modifies cerebral hemodynamics and functional connectivity in depressive patients, as evidenced by fNIRS metrics. This study underscores the utility of fNIRS for objective neurobiological monitoring in ECT treatment.

Decision-making power enhances investors' neural processing of persuasive message in partnership investment

Partnership investment is a common form of business where investors have different levels of power and need to persuade each other to reach a consensus. This study investigated the neural mechanisms underlying the impact of decision-making power on persuasive communication in partnership investment, aiming to provide neural evidence to test two competing hypotheses: the power-responsibility hypothesis and the power-overconfidence hypothesis. Using functional near-infrared spectroscopy (fNIRS), we recorded brain activity from persuader-receiver dyads as they engaged in a partnership investment task. Behavioral results showed that receivers' decisions were more affected by persuaders' persuasive messages when receivers had dominant decision-making power. Neurally, the functional connectivity (FC) between the left and right temporo-parietal junctions (lTPJ and rTPJ) of the receiver was significantly increased by their decision-making power. Additionally, we identified four pairs of interpersonal neural synchronization (INS) that exhibited significant enhancement when persuaders used numeric persuasion rather than non-numeric persuasion: lTPJ-rTPJ, left superior temporal gyrus (lSTG)-rTPJ, left middle temporal gyrus (lMTG)-rTPJ, and medial prefrontal cortex (mPFC)-lTPJ. The decision-making power amplified the INS difference in the last three pairs. Furthermore, using a support vector machine (SVM) algorithm, the INS could accurately predict receivers' adoption of persuasive messages when they held dominant decision-making power. Finally, we found that FC at lTPJ-rTPJ and INS at lSTG-rTPJ were positively associated with receivers' adoption of persuasive messages as well. Our study clarifies how decision-making power alters the way individuals process persuasive messages in partnership investment, providing insights into the neural basis of persuasion in group decision-making contexts and supporting the power-responsibility hypothesis.

Structured interaction between teacher and student in the flipped classroom enhances learning and interbrain synchrony

Studies have found that flipped classroom teaching (FT) improves learning compared to lecture-based teaching (LT). However, whether the structured teacher-student interaction-the key feature of FT-plays an essential role in enhancing learning remains unclear, as do its neural underpinnings. Here, we compared three teaching conditions: FT with a video lecture and structured interaction, LT with a face-to-face lecture and spontaneous interaction, and control teaching (CT) with a video lecture and spontaneous interaction. The fNIRS-based hyperscanning technique was used to assess the interbrain synchrony (IBS) from teacher-student dyads. Results showed that the learning was significantly improved in FT than in LT and CT, and FT significantly increased teacher-student IBS in left DLPFC. Moreover, the IBS and learning improvements were positively correlated. Therefore, these findings indicate that the structured teacher-student interaction is crucial for enhancing learning in FT, and IBS serves as its neural foundation.

Memory detection with concurrent behavioral, autonomic, and neuroimaging measures in a mock crime

Concealed information test (CIT) has been utilized for long to perform single measurements. The combination of multiple measures outperforms single measures because of the diverse cognitive processes they reflect and the reduction in random errors facilitated by multiple measures. To further explore the performance of the CIT with multiple measurements, 57 participants were recruited and randomly assigned into guilty and innocent groups. Subsequently, simultaneously recorded reaction time (RT), skin conductance responses (SCRs), heart rate (HR), and neuroimaging data were collected from functional near-infrared spectroscopy (fNIRS) to detect participants' concealed information in a standard CIT. The results demonstrated that all indicators including RT (area under the curve (AUC) = 0.87), SCRs (AUC = 0.79), HR (AUC = 0.78), and fNIRS (channel 8, AUC = 0.85) could differentiate guilty and innocent groups. Importantly, the use of multiple indicators achieved higher detection efficiency (AUC = 0.96) compared to the use of any single indicator. These results illustrate the effectiveness and feasibility of integrating multiple indicators for concealed information detection in CIT.

Atypical prefrontal neural activity during an emotional interference control task in adolescents with autism spectrum disorder: A functional near-infrared spectroscopy study

Autism spectrum disorder (ASD) is typically characterized by impairments in social interaction and communication, which may be associated with a failure to naturally orient to social stimuli, particularly in recognizing and responding to facial emotions. As most previous studies have used nonsocial stimuli to investigate inhibitory control in children and adults with ASD, little is known about the behavioral and neural activation patterns of emotional inhibitory control in adolescent with ASD. Functional neuroimaging studies have underscored the key role of the prefrontal cortex (PFC) in inhibitory control and emotional face processing. Thus, this study aimed to examine whether adolescent with ASD exhibited altered PFC processing during an emotional Flanker task by using non-invasive functional near-infrared spectroscopy (fNIRS). Twenty-one adolescents with high-functioning ASD and 26 typically developing (TD) adolescents aged 13-16 years were recruited. All participants underwent an emotional Flanker task, which required to decide whether the centrally positioned facial emotion is consistent with the laterally positioned facial emotion. TD adolescents exhibited larger RT and mean O2Hb level in the incongruent condition than the congruent condition, evoking cortical activations primarily in right PFC regions in response to the emotional Flanker effect. In contrast, ASD adolescents failed to exhibit the processing advantage for congruent versus incongruent emotional face in terms of RT, but showed cortical activations primarily in left PFC regions in response to the emotional Flanker effect. These findings suggest that adolescents with ASD rely on different neural strategies to mobilize PFC neural resources to address the difficulties they experience when inhibiting the emotional face.

Client-counselor behavioral and inter-brain synchronization among dismissing and secure clients and its association with alliance quality and outcome

Objective This study aimed to explore whether behavioral synchrony (BS) and inter-brain synchrony (IBS) could serve as potential biomarkers for alliance quality or outcomes among clients with different adult attachment styles. Method: We assessed the clients' self-report working alliance and clinical outcomes as well as simultaneously measured BS using motion energy analysis (MEA) and IBS with functional near-infrared spectroscopy (fNIRS) among 37 secure (N = 21) or dismissing (N = 16) clients with their counselors during the first psychological counseling meeting. Results: Dismissing dyads manifested significantly higher late-stage counselor-led and client-led IBS (p = .018) than secure dyads. Adult attachment style served as the moderators in the correlation of both whole-stage client-led BS with bond dimension of alliance (p = .015) as well as in the correlation of both whole-stage no-lag IBS with CORE-10 score changes (p = .022). Moreover, increases in the whole-stage client-led BS were significantly associated with decreases in early-stage, late-stage and whole-stage no-lag IBS (all ps ≤ 0.01). Conclusion: These findings revealed the potentially impeding role of interpersonal synchrony in alliance quality for dismissing clients, at least during the first psychological counseling meetings. They also might partially validate the relationship between different modalities of interpersonal synchrony.

Cross-modal representation of chewing food in posterior parietal and visual cortex

Even though the oral cavity is not visible, food chewing can be performed without damaging the tongue, oral mucosa, or other intraoral parts, with cross-modal perception of chewing possibly critical for appropriate recognition of its performance. This study was conducted to clarify the relationship of chewing food cross-modal perception with cortex activities based on examinations of the posterior parietal cortex (PPC) and visual cortex during chewing in comparison with sham chewing without food, imaginary chewing, and rest using functional near-infrared spectroscopy. Additionally, the effects of a deafferent tongue dorsum on PPC/visual cortex activities during chewing performance were examined. The results showed that chewing food increased activity in the PPC/visual cortex as compared with imaginary chewing, sham chewing without food, and rest. Nevertheless, those activities were not significantly different during imaginary chewing or sham chewing without food as compared with rest. Moreover, subjects with a deafferent tongue dorsum showed reduced PPC/visual cortex activities during chewing food performance. These findings suggest that chewing of food involves cross-modal recognition, while an oral somatosensory deficit may modulate such cross-modal activities.

The DLPFC is centrally involved in resolving Stroop conflicts, suppressing distracting sensory input within the auditory and visual system

Introduction

Cognitive control is a prerequisite for successful, goal-oriented behavior. The dorsolateral prefrontal cortex (DLPFC) is assumed to be a key player in applying cognitive control; however, the neural mechanisms by which this process is accomplished are still unclear.

Methods

To further address this question, an audiovisual Stroop task was used, comprising simultaneously presented pictures and spoken names of actors and politicians. Depending on the task block, participants had to indicate whether they saw the face or heard the name of a politician or an actor (visual vs. auditory blocks). In congruent trials, both stimuli (visual and auditory) belonged to the same response category (actor or politician); in incongruent trials, they belonged to different categories. During this task, activity in sensory target regions was measured via functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG), respectively. Specifically, fNIRS was used to monitor activity levels within the auditory cortex, while the EEG-based event-related potential of the N170 was considered as a marker of FFA (fusiform face area) involvement. Additionally, we assessed the effects of inhibitory theta-burst stimulation-a specific protocol based on repetitive transcranial magnetic stimulation (rTMS)-over the right DLPFC. Non-invasive brain stimulation is one of the few means to draw causal conclusions in human neuroscience. In this case, rTMS was used to temporarily inhibit the right DLPFC as a presumed key player in solving Stroop conflicts in one of two measurement sessions; then, effects were examined on behavioral measures as well as neurophysiological signals reflecting task-related activity in the frontal lobes and sensory cortices.

Results

The results indicate a central role of the DLPFC in the implementation of cognitive control in terms of a suppression of distracting sensory input in both the auditory cortex and visual system (FFA) in high-conflict situations. Behavioral data confirm a reduced Stroop effect following previous incongruent trials ("Gratton effect") that was only accomplished with an intact DLPFC (i.e., following placebo stimulation).

Discussion

Because non-invasive brain stimulation is uniquely suited to causally test neuroscientific hypotheses in humans, these data give important insights into some of the mechanisms by which the DLPFC establishes conflict resolution across different sensory modalities.

Different neural correlates of deception: Crafting high and low creative scams

Deception is a complex social behavior that manifests in various forms, including scams. To successfully deceive victims, liars have to continually devise novel scams. This ability to create novel scams represents one kind of malevolent creativity, referred to as lying. This study aimed to explore different neural substrates involved in the generation of high and low creative scams. A total of 40 participants were required to design several creative scams, and their cortical activity was recorded by functional near-infrared spectroscopy. The results revealed that the right frontopolar cortex (FPC) was significantly active in scam generation. This region associated with theory of mind may be a key region for creating novel and complex scams. Moreover, creativity-related regions were positively involved in creative scams, while morality-related areas showed negative involvement. This suggests that individuals might attempt to use malevolent creativity while simultaneously minimizing the influence of moral considerations. The right FPC exhibited increased coupling with the right precentral gyrus during the design of high-harmfulness scams, suggesting a diminished control over immoral thoughts in the generation of harmful scams. Additionally, the perception of the victim's emotions (related to right pre-motor cortex) might diminish the quality of highly original scams. Furthermore, an efficient and cohesive neural coupling state appears to be a key factor in generating high-creativity scams. These findings suggest that the right FPC was crucial in scam creation, highlighting a neural basis for balancing malevolent creativity against moral considerations in high-creativity deception.

Dynamic brain networks in spontaneous gestural communication

Gestures accent and illustrate our communication. Although previous studies have uncovered the positive effects of gestures on communication, little is known about the specific cognitive functions of different types of gestures, or the instantaneous multi-brain dynamics. Here we used the fNIRS-based hyperscanning technique to track the brain activity of two communicators, examining regions such as the PFC and rTPJ, which are part of the mirroring and mentalizing systems. When participants collaboratively solved open-ended realistic problems, we characterised the dynamic multi-brain states linked with specific social behaviours. Results demonstrated that gestures are associated with enhanced team performance, and different gestures serve distinct cognitive functions: interactive gestures are accompanied by better team originality and a more efficient inter-brain network, while fluid gestures correlate with individual cognitive fluency and efficient intra-brain states. These findings reveal a close association between social behaviours and multi-brain networks, providing a new way to explore the brain-behaviour relationship.

Lights on music cognition: A systematic and critical review of fNIRS applications and future perspectives

Research investigating the neural processes related to music perception and production constitutes a well-established field within the cognitive neurosciences. While most neuroimaging tools have limitations in studying the complexity of musical experiences, functional Near-Infrared Spectroscopy (fNIRS) represents a promising, relatively new tool for studying music processes in both laboratory and ecological settings, which is also suitable for both typical and pathological populations across development. Here we systematically review fNIRS studies on music cognition, highlighting prospects and potentialities. We also include an overview of fNIRS basic theory, together with a brief comparison to characteristics of other neuroimaging tools. Fifty-nine studies meeting inclusion criteria (i.e., using fNIRS with music as the primary stimulus) are presented across five thematic sections. Critical discussion of methodology leads us to propose guidelines of good practices aiming for robust signal analyses and reproducibility. A continuously updated world map is proposed, including basic information from studies meeting the inclusion criteria. It provides an organized, accessible, and updatable reference database, which could serve as a catalyst for future collaborations within the community. In conclusion, fNIRS shows potential for investigating cognitive processes in music, particularly in ecological contexts and with special populations, aligning with current research priorities in music cognition.

Distinction of mental health between salesman and R&D in high-tech enterprise: a fNIRS study

Employees in enterprises face numerous challenges due to the severe employment situation and job pressure. Sales personnel and research and development (R&D) personnel in companies are particularly susceptible to mental health issues due to the unique nature and complexity of their work. This study aims to explore the psychological health issues among sales personnel and R&D personnel in high-tech enterprises. Twenty-four R&D personnel (23 males and 1 female) and twenty-six sales personnel (25 males and 1 female) were recruited. The participants' psychological health conditions were assessed using the Symptom Checklist-90 (SCL-90) and verbal fluency tasks combined with functional near-infrared spectroscopy (VFT-fNIRS), while their work stress level was evaluated using the Personal Stress Questionnaire (PSQ) and Personal Resources Questionnaire (PRQ). The results indicated significantly higher brain activities in the right dorsolateral prefrontal cortex and bilateral Broca's areas of the R&D group compared to the sales group. The R&D group had significantly lower scores in the total score and multiple dimensions of SCL-90, such as somatization, obsession-compulsion, depression, anxiety, hostility, and paranoia. In addition, the R&D group exhibited significantly lower psychological and physical tension reactions compared to the sales group in PSQ. Based on the PRQ, the R&D group obtained significantly higher scores in self-care compared to the sales group. In conclusion, the mental health status of the R&D group is better than that of the sales group, the difference in self-care may be the most important factor leading to the difference in work stress and mental health of the two groups, VFT-fNIRS might be used to assist in detecting the mental health status of employees.

Neural and Physiological Correlates of Prosocial Behavior: Temporoparietal Junction Activity in 3-year-old Children

Although the development of prosocial behavior has been widely studied from the behavioral aspect, the neural mechanisms underlying prosocial behavior in the early stages of development remain unclear. Therefore, this study investigated the neural mechanisms underlying the emergence of prosocial behavior in 3-year-old children. Brain activity in the medial pFC and right TPJ (rTPJ) and facial expression activity, which are related to the ability to infer others' mental states (mentalizing), during the observation of prosocial and antisocial scenes were measured using functional near-infrared spectroscopy and electromyography, respectively. Subsequently, the children's helping and comforting behaviors toward an experimenter were assessed to examine prosocial behavioral tendencies. A correlation analysis revealed that the children who showed stronger activity levels in the rTPJ while observing prosocial scenes had more immediate helping behaviors toward others than those who did not show stronger response levels. Moreover, the amount of facial expression activity correlated with prosocial behavior, including both helping and comforting behaviors. These results suggest that the development of mentalizing ability and the social evaluation of others' actions, mediated by the rTPJ, contribute to the emergence of prosocial behavior.

Neurological activation during verbal fluency task and resting-state functional connectivity abnormalities in obsessive-compulsive disorder: a functional near-infrared spectroscopy study

Objective

This study aims to investigate the activation of frontotemporal functional brain areas in patients with Obsessive-Compulsive Disorder (OCD) during a Verbal Fluency Task (VFT), and to compare their brain functional connectivity in a resting state with that of healthy controls. The goal is to deepen our understanding of the neuropathological mechanisms underlying OCD.

Methods

32 patients with OCD and 32 controls matched for age, gender, handedness, and years of education participated in this study, they were divided into OCD group and healthy comtrol group. We conducted VFT task tests and 10-minute resting state tests on both groups by using functional Near-Infrared Spectroscopy (fNIRS). The VFT was utilized to assess the activation (beta values) and the integral and centroid values of the frontal and bilateral temporal lobes, including brain areas BA9 and 46 (dorsolateral prefrontal cortex), BA10 (frontal pole), BA45 (inferior frontal gyrus), BA21 (middle temporal gyrus), and BA22 (superior temporal gyrus). We evaluated the functional connectivity levels of these areas during the resting state. Differences in these measures between OCD patients and healthy controls were analyzed using two-sample independent t-tests and non-parametric Mann-Whitney U tests.

Results

During VFT, OCD had smaller integral values(z=5.371, p<0.001; t=4.720, p<0.001), and larger centroid values(t=-2.281, p=0.026; z=-2.182, p=0.029) compared to healthy controls, along with a reduced number of activated channels detected by fNIRS. Additionally, activation values (β) in various functional brain areas, including BA9, BA46, BA10, BA45, BA21, and BA22, were significantly lower in the OCD group (all p< 0.01). In the resting state, notable disparities in functional connectivity were observed between the inferior frontal gyrus (IFG) and dorsolateral prefrontal cortex (DLPFC) in the OCD group, in comparison to the control group. Specifically, there was a significant increase in connectivity between the left IFG and right DLPFC, suggesting the presence of altered connectivity patterns in these areas.

Conclusions

The study highlights significant disparities in neural activation and functional connectivity between OCD patients and healthy controls during VFT. Specifically, reduced activation was noted in the frontal and bilateral temporal lobes of OCD patients, alongside alterations in resting-state functional connectivity between the IFG and DLPFC. These findings contribute to our understanding of the neurobiological underpinnings of OCD and may guide future therapeutic strategies.

Investigating the relationship between CSAT scores and prefrontal fNIRS signals during cognitive tasks using a quantum annealing algorithm

Academic achievement is a critical measure of intellectual ability, prompting extensive research into cognitive tasks as potential predictors. Neuroimaging technologies, such as functional near-infrared spectroscopy (fNIRS), offer insights into brain hemodynamics, allowing understanding of the link between cognitive performance and academic achievement. Herein, we explored the association between cognitive tasks and academic achievement by analyzing prefrontal fNIRS signals. A novel quantum annealer (QA) feature selection algorithm was applied to fNIRS data to identify cognitive tasks correlated with CSAT scores. Twelve features (signal mean, median, variance, peak, number of peaks, sum of peaks, range, minimum, kurtosis, skewness, standard deviation, and root mean square) were extracted from fNIRS signals at two time windows (10- and 60-s) to compare results from various feature variable conditions. The feature selection results from the QA-based and XGBoost regressor algorithms were compared to validate the former's performance. In a two-step validation process using multiple linear regression models, model fitness (adjusted R2) and model prediction error (RMSE) values were calculated. The quantum annealer demonstrated comparable performance to classical machine learning models, and specific cognitive tasks, including verbal fluency, recognition, and the Corsi block tapping task, were correlated with academic achievement. Group analyses revealed stronger associations between Tower of London and N-back tasks with higher CSAT scores. Quantum annealing algorithms have significant potential in feature selection using fNIRS data, and represents a novel research approach. Future studies should explore predictors of academic achievement and cognitive ability.

The acquired dyad inclination and decreased interpersonal brain communication in the pursuit of collective benefit

People perform better collectively than individually, a phenomenon known as the collective benefit. To pursue the benefit, they may learn from previous behaviors, come to know whose initial opinion should be valued, and develop the inclination to take it as the collective one. Such learning may affect interpersonal brain communication. To test these hypotheses, this study recruited participant dyads to conduct a perceptual task on which they made individual decisions first and then the collective one. The enhanced interpersonal brain synchronization (IBS) between participants was explored when individual decisions were in disagreement vs. agreement. Computational modeling revealed that participant dyads developed the dyad inclination of taking the higher-able participants', not the lower-able ones' decisions as their collective ones. Brain analyses unveiled the enhanced IBS at frontopolar areas, premotor areas, supramarginal gyri, and right temporal-parietal junctions. The premotor IBS correlated negatively with dyad inclination and collective benefit in the absence of correction. The Granger causality analyses further supported the negative relation of dyad inclination with inter-brain communication. This study highlights that dyads learn to weigh individuals' decisions, resulting in dyad inclinations, and explores associated inter-brain communication, offering insights into the dynamics of collective decision-making.

Teach a man to fish: Hyper-brain evidence on scaffolding strategy enhancing creativity acquisition and transfer

Creativity is an indispensable competency in today's innovation-driven society. Yet, the influences of instructional strategy, a key determinant of educational outcomes, on the creativity-fostering process remains an unresolved mystery. We proposed that instructional strategy affects creativity cultivation and further investigated the intricate neural mechanisms underlying this relationship. In a naturalistic laboratory setting, 66 instructor-learner dyads were randomized into three groups (scaffolding, explanation, and control), with divergent thinking instructions separately. Functional near-infrared spectroscopy (fNIRS) hyperscanning simultaneously collected brain signals in the prefrontal cortex and temporal-parietal junction regions. Results indicated that learners instructed with a scaffolding strategy demonstrated superior creative performance both in acquisition (direct learning) and transfer (use in a novel context) of creativity skills, compared to pretest levels. In contrast, the control and explanation groups did not exhibit such effects. Notably, we also observed remarkable interbrain neural synchronization (INS) between instructors and learners in the left superior frontal cortex in the scaffolding group, but not in the explanation or control groups. Furthermore, INS positively predicted enhancements in creativity performance (acquisition and transfer), indicating that it is a crucial neural mechanism in the creativity-fostering process. These findings reveal that scaffolding facilitates the acquisition and transfer of creativity and deepen our understanding of the neural mechanisms underlying the process of creativity-fostering. The current study provides valuable insights for implementing teaching strategies to fostering creativity.

Concurrent behavioral modeling and multimodal neuroimaging reveals how feedback affects the performance of decision making in internet gaming disorder

Internet gaming disorder (IGD) prompts inquiry into how feedback from prior gaming rounds influences subsequent risk-taking behavior and potential neural mechanisms. Forty-two participants, including 15 with IGD and 27 health controls (HCs), underwent a sequential risk-taking task. Hierarchy Bayesian modeling was adopted to measure risky propensity, behavioral consistence, and affection by emotion ratings from last trial. Concurrent electroencephalogram and functional near-infrared spectroscopy (EEG-fNIRS) recordings were performed to demonstrate when, where and how the previous-round feedback affects the decision making to the next round. We discovered that the IGD illustrated heightened risk-taking propensity as compared to the HCs, indicating by the computational modeling (p = 0.028). EEG results also showed significant time window differences in univariate and multivariate pattern analysis between the IGD and HCs after the loss of the game. Further, reduced brain activation in the prefrontal cortex during the task was detected in IGD as compared to that of the control group. The findings underscore the importance of understanding the aberrant decision-making processes in IGD and suggest potential implications for future interventions and treatments aimed at addressing this behavioral addiction.

Hemodynamic activity is not parsimoniously tuned to index-of-difficulty in movement with dual requirements on speed-accuracy

Background

Reaching movements are crucial for daily living and rehabilitation, for which Fitts' Law describes a speed-accuracy trade-off that movement time increases with task difficulty. This study aims to investigate whether cortical activation in motor-related areas is directly linked to task difficulty as defined by Fitts' Law. Understanding this relationship provides a physiological basis for parameter selection in therapeutic exercises.

Methods

Sixteen healthy subjects performed 2D reaching movements using a rehabilitation robot, with their cortical responses detected using functional near-infrared spectroscopy (fNIRS). Task difficulty was manipulated by varying target size and distance, resulting in 3 levels of index-of-difficulty (ID). Kinematic signals were recorded alongside cortical activity to assess the relationship among movement time, task difficulty, and cortical activation.

Results

Our results showed that movement time increased with ID by 0.2974s/bit across all subjects (conditional r2 = 0.6434, p < 0.0001), and all subjects showed individual trends conforming Fitts' Law (all p < 0.001). Neither activation in BA4 nor in BA6 showed a significant correlation with ID (p > 0.05), while both the target size and distance, as well as the interaction between them, showed a significant relationship with BA4 or BA6 activation (all p < 0.05).

Conclusion

This study found that although kinematic measures supported Fitts' Law, cortical activity in motor-related areas during reaching movements did not correlate directly with task difficulty as defined by Fitts' Law. Additional factors such as muscle activation may call for different cortical control even when difficulty was identical.

Event-related prefrontal activations during online video game playing are modulated by game mechanics, physiological arousal and the amount of daily playing

There is a trend to study human brain functions in ecological contexts and in relation to human factors. In this study, functional near-infrared spectroscopy (fNIRS) was used to record real-time prefrontal activities in 42 male university student habitual video game players when they played a round of multiplayer online battle arena game, League of Legends. A content-based event coding approach was used to analyze regional activations in relation to event type, physiological arousal indexed by heart rate (HR) change, and individual characteristics of the player. Game events Slay and Slain were found to be associated with similar HR and prefrontal responses before the event onset, but differential responses after the event onset. Ventrolateral prefrontal cortex (VLPFC) activation preceding the Slay onset correlated positively with HR change, whereas activations in dorsolateral prefrontal cortex (DLPFC) and rostral frontal pole area (FPAr) preceding the Slain onset were predicted by self-reported hours of weekly playing (HoWP). Together, these results provide empirical evidence to support the notion that event-related regional prefrontal activations during online video game playing are shaped by game mechanics, in-game dynamics of physiological arousal and individual characteristics the players.

Anxiety symptoms without depression are associated with cognitive control network (CNN) dysfunction: An fNIRS study

Anxiety is a common psychological disorder associated with other mental disorders, with depression being the most common comorbidity. Few studies have examined the neural mechanisms underlying anxiety after controlling for depression. This study aimed to explore whether there are differences in cortical activation in anxiety patients with different severities whose depression are normal. In the current study, depression levels were normal for 366 subjects-139 healthy subjects, 117 with mild anxiety, and 110 with major anxiety. Using the Hospital Anxiety and Depression Scale (HADS) and a verbal fluency task (VFT) to test subjects' anxiety and depression and cognitive function, respectively. A 53-channel guided near-infrared spectroscopic imaging technology (fNIRS) detected the concentration of oxyhemoglobin (oxy-Hb). Correlation analysis between anxiety severity and oxy-Hb concentration in the brain cortex was performed, as well as ANOVA analysis of oxy-Hb concentration among the three anxiety severity groups. The results showed that anxiety severity was significantly and negatively correlated with oxy-Hb concentrations in the left frontal eye field (lFEF) and in the right dorsolateral prefrontal area (rDLPFC). The oxy-Hb concentration in the lFEF and the rDLPFC were significantly lower in the major anxiety disorder group than that in the control group. This suggests that decreased cortical activity of the lFEF and rDLPFC may be neural markers of anxiety symptoms after controlling for depression. Anxiety symptoms without depression may be result from the dysfunction of the cognitive control network (CCN) which includes the lFEF and rDLPFC.

Enhancing Agency in Individuals with Depressive Symptoms: The Roles of Effort, Outcome Valence, and Its Underlying Cognitive Mechanisms and Neural Basis

Background

Agency, a sense of control over one's actions and outcomes, is crucial for recovery from depressive symptoms. However, the mechanisms that enhance agency in individuals with depressive symptoms remain poorly understood. This study endeavors to elucidate these fundamental processes.

Materials and Methods

We recruited 52 participants exhibiting depressive symptoms to participate in a novel Judgment of Agency (JoA) task. This task was structured with a 3 (effort: high load, medium load, low load) × 2 (outcome: win, miss) within-subject design to assess the impact of effort and outcome valence on agency. Throughout the task, we utilized functional near-infrared spectroscopy (fNIRS) to explore the neural mechanisms underlying agency. Furthermore, we conducted a randomized, sham-controlled, pre-post-test trial involving intermittent theta-burst stimulation (iTBS) targeted at the left dorsolateral prefrontal cortex (DLPFC) to investigate its potential to enhance agency. Participants were randomly allocated to either an active iTBS group or a sham group, with each receiving a single session of stimulation (600 pulses). The JoA task was conducted both before and after the stimulation.

Results

Effort significantly influenced agency in individuals with depressive symptoms, with this effect being moderated by the outcomes' valences. Agency was positively correlated with self-efficacy (r = 0.28, P < 0.05) when goals were achieved with effort, and with anxiety severity (r = 0.29, P < 0.05) when goals were not achieved. Additionally, it was associated with the activation of several frontal brain regions (all P values < 0.01), including the left DLPFC, right premotor and supplementary motor areas, and the left inferior frontal gyrus (IFG). Application of iTBS over the left DLPFC significantly enhanced self-attributed agency, particularly when the outcomes were achieved under conditions of low-load effort.

Conclusions

Our study highlights the critical role of effort in enhancing agency for individuals with depressive symptoms, with iTBS applied to the left DLPFC showing potential to enhance agency postgoal achievement. Moreover, the activation of the left IFG and the presence of anxiety are associated with maladaptive self-attributed agency, offering potential targets for therapeutic intervention.

Impact of ASL Exposure on Spoken Phonemic Discrimination in Adult CI Users: A Functional Near-Infrared Spectroscopy Study

We examined the impact of exposure to a signed language (American Sign Language, or ASL) at different ages on the neural systems that support spoken language phonemic discrimination in deaf individuals with cochlear implants (CIs). Deaf CI users (N = 18, age = 18-24 yrs) who were exposed to a signed language at different ages and hearing individuals (N = 18, age = 18-21 yrs) completed a phonemic discrimination task in a spoken native (English) and non-native (Hindi) language while undergoing functional near-infrared spectroscopy neuroimaging. Behaviorally, deaf CI users who received a CI early versus later in life showed better English phonemic discrimination, albeit phonemic discrimination was poor relative to hearing individuals. Importantly, the age of exposure to ASL was not related to phonemic discrimination. Neurally, early-life language exposure, irrespective of modality, was associated with greater neural activation of left-hemisphere language areas critically involved in phonological processing during the phonemic discrimination task in deaf CI users. In particular, early exposure to ASL was associated with increased activation in the left hemisphere's classic language regions for native versus non-native language phonemic contrasts for deaf CI users who received a CI later in life. For deaf CI users who received a CI early in life, the age of exposure to ASL was not related to neural activation during phonemic discrimination. Together, the findings suggest that early signed language exposure does not negatively impact spoken language processing in deaf CI users, but may instead potentially offset the negative effects of language deprivation that deaf children without any signed language exposure experience prior to implantation. This empirical evidence aligns with and lends support to recent perspectives regarding the impact of ASL exposure in the context of CI usage.

Effects of age on the interactions of attentional and emotional processes: a prefrontal fNIRS study

The aging of attentional and emotional functions has been extensively studied but relatively independently. Therefore, the relationships between aging and the interactions of attentional and emotional processes remain elusive. This study aimed to determine how age affected the interactions between attentional and emotional processes during adulthood. One-hundred forty adults aged 18-79 performed the emotional variant of the Attention Network Test, which probed alerting, orienting, and executive control in the presence and absence of threatening faces. During this task, contexts with varying levels of task preparatory processes were created to modulate the effect of threatening faces on attention, and functional near-infrared spectroscopy (fNIRS) was used to examine the neural underpinnings of the behavioural effects. The behavioural results showed that aging was associated with a significant decline in alerting efficiency, and there was a statistical trend for age-related deficits in executive control. Despite these age differences, age did not significantly moderate the interactions among attentional networks or between attention and emotion. Additionally, the fNIRS results showed that decreased frontal cortex functioning might underlie the age-related decline in executive control. Therefore, while aging has varying effects on different attentional networks, the interactions of attentional and emotional processes remain relatively unaffected by age.

The most fundamental and popular literature on functional near-infrared spectroscopy: a bibliometric analysis of the top 100 most cited articles

Background

Functional near infrared spectroscopy (fNIRS) has developed rapidly in recent years, and there are more and more studies on fNIRS. At present, there is no bibliometric analysis of the top 100 most cited articles on fNIRS research.

Objective

To identify the top 100 most cited articles on fNIRS and analyze those most fundamental and popular articles through bibliometric research methods.

Methods

The literature on fNIRS of web of science from 1990 to 2023 was searched and the top 100 most cited articles were identified by citations. Use the bibliometrix package in R studio and VOSviewer for data analysis and plotting to obtain the output characteristics and citation status of these 100 most cited articles, and analyze research trends in this field through keywords.

Results

A total of 9,424 articles were retrieved from web of science since 1990. The average citation number of the 100 articles was 457.4 (range from 260 to 1,366). Neuroimage published the most articles (n = 31). Villringer, A. from Leipzig University had the largest number of top 100 papers. Harvard University (n = 22) conducted most cited articles. The United States, Germany, Japan, and the United Kingdom had most cited articles, respectively. The most common keywords were near-infrared spectroscopy, activation, cerebral-blood-flow, brain, newborn-infants, oxygenation, cortex, fMRI, spectroscopy. The fund sources mostly came from National Institutes of Health Unitd States (NIH) and United States Department of Health Human Services (n = 28).

Conclusion

Neuroimage was the most popular journal. The top countries, institutions, and authors were the United States, Harvard University, and Villringer, A., respectively. Researchers and institutions from North America and Europe contributed the most. Near-infrared spectroscopy, activation, cerebral-blood-flow, brain, newborn-infants, oxygenation, cortex, fmri, spectroscopy, stimulation, blood-flow, light-propagation, infants, tissue comprise the future research directions and potential topic hotspots for fNIRS.

Prefrontal cortex activity and functional organisation in dual-task ocular pursuit is affected by concurrent upper limb movement

Tracking a moving object with the eyes seems like a simple task but involves areas of prefrontal cortex (PFC) associated with attention, working memory and prediction. Increasing the demand on these processes with secondary tasks can affect eye movements and/or perceptual judgments. This is particularly evident in chronic or acute neurological conditions such as Alzheimer's disease or mild traumatic brain injury. Here, we combined near infrared spectroscopy and video-oculography to examine the effects of concurrent upper limb movement, which provides additional afference and efference that facilitates tracking of a moving object, in a novel dual-task pursuit protocol. We confirmed the expected effects on judgement accuracy in the primary and secondary tasks, as well as a reduction in eye velocity when the moving object was occluded. Although there was limited evidence of oculo-manual facilitation on behavioural measures, performing concurrent upper limb movement did result in lower activity in left medial PFC, as well as a change in PFC network organisation, which was shown by Graph analysis to be locally and globally more efficient. These findings extend upon previous work by showing how PFC is functionally organised to support eye-hand coordination when task demands more closely replicate daily activities.

The neurocomputational signature of decision-making for unfair offers in females under acute psychological stress

Stress is a crucial factor affecting social decision-making. However, its impacts on the behavioral and neural processes of females' unfairness decision-making remain unclear. Combining computational modeling and functional near-infrared spectroscopy (fNIRS), this study attempted to illuminate the neurocomputational signature of unfairness decision-making in females. We also considered the effect of trait stress coping styles. Forty-four healthy young females (20.98 ± 2.89 years) were randomly assigned to the stress group (n = 21) and the control group (n = 23). Acute psychosocial stress was induced by the Trier Social Stress Test (TSST), and participants then completed the one-shot ultimatum game (UG) as responders. The results showed that acute psychosocial stress reduced the adaptability to fairness and lead to more random decision-making responses. Moreover, in the stress group, a high level of negative coping style predicted more deterministic decision. fNIRS results showed that stress led to an increase of oxy-hemoglobin (HbO) peak in the right temporoparietal junction (rTPJ), while decreased the activation of left middle temporal gyrus (lMTG) when presented the moderately unfair (MU) offers. This signified more involvement of the mentalization and the inhibition of moral processing. Moreover, individuals with higher negative coping scores showed more deterministic decision behaviors under stress. Taken together, our study emphasizes the role of acute psychosocial stress in affecting females' unfairness decision-making mechanisms in social interactions, and provides evidences for the "tend and befriend" pattern based on a cognitive neuroscience perspec.

Left OFC Activation in Functional Near-Infrared Spectroscopy during an Inhibitory Control Task in an Early Years Sample: Integrating Stress Responses with Cognitive Function and Brain Activation

INTRODUCTION

Previous functional near-infrared spectroscopy (fNIRS) studies using Go/No-Go (GNG) tasks have focused on brain activation in relation to cognitive processes, particularly inhibitory control (IC). The results of these studies commonly describe right hemispheric engagement of the dorsolateral, ventromedial, or inferior frontal regions of the prefrontal cortex. Considering that typical healthy cognitive development is negatively correlated with higher cortisol levels (which may alter brain development), the overarching aim of the current study was to investigate how elevated stress (due to unforeseeable events such as the pandemic) impacts early cognitive development.

METHOD

In this study, we examined fNIRS data collected from a sample of children (aged 2-4 years) during a GNG task relative to the response to stressors measured via hair cortisol concentrations. We acquired data in an ecological setting (Early Childhood Education and Care) during the coronavirus pandemic.

RESULTS

We found that children with higher stress levels and a less efficient IC recruited more neural terrain and our group-level analysis indicated activation in the left orbitofrontal area during IC performance.

CONCLUSIONS

A contextual stressor may disrupt accuracy in the executive function of IC early in development. More research efforts are needed to understand better how an orbitofrontal network subserves goal-directed behavior.

INTRODUCTION

Previous functional near-infrared spectroscopy (fNIRS) studies using Go/No-Go (GNG) tasks have focused on brain activation in relation to cognitive processes, particularly inhibitory control (IC). The results of these studies commonly describe right hemispheric engagement of the dorsolateral, ventromedial, or inferior frontal regions of the prefrontal cortex. Considering that typical healthy cognitive development is negatively correlated with higher cortisol levels (which may alter brain development), the overarching aim of the current study was to investigate how elevated stress (due to unforeseeable events such as the pandemic) impacts early cognitive development.

METHOD

In this study, we examined fNIRS data collected from a sample of children (aged 2-4 years) during a GNG task relative to the response to stressors measured via hair cortisol concentrations. We acquired data in an ecological setting (Early Childhood Education and Care) during the coronavirus pandemic.

RESULTS

We found that children with higher stress levels and a less efficient IC recruited more neural terrain and our group-level analysis indicated activation in the left orbitofrontal area during IC performance.

CONCLUSIONS

A contextual stressor may disrupt accuracy in the executive function of IC early in development. More research efforts are needed to understand better how an orbitofrontal network subserves goal-directed behavior.

Physical training improves inhibitory control in children aged 7-12 years: An fNIRS study

Physical exercise plays a crucial role in the development of cognition and brain functions in children. Inhibitory control is an advanced cognition that affects children's life and learning. In the current study, the relationship between physical training and inhibitory control was explored. In total, 80 children were randomly but equally assigned to the experimental and control groups. The experimental group underwent physical training (volleyball) for 60 min, thrice a week for 12 weeks. In contrast, the control group did not undergo any training and continued with their daily routines. The flanker task and functional near-infrared spectroscopy (fNIRS) were employed to investigate the effects of 12-week physical training on inhibitory control and changes in the oxy-Hb concentration in the prefrontal cortex (PFC) during the task. The behavioral results revealed that the experimental group performed better on the flanker task (e.g., shorter response time [F(1,74) = 18.420, p < 0.001, ηp2 = 0.199] and higher accuracy [F(1,74) = 15.00, p < 0.001, ηp2 = 0.169] than the control group. The oxy-Hb concentration in the right dorsolateral PFC (R-DLPFC) was higher and the activation level of this region was higher during the flanker task [F(1,74) = 6.216, p < 0.05, ηp2 = 0.077]. Moreover, the McNemar test revealed improved cognitive performance in response time or accuracy and R-DLPFC activation induced by physical exercise coincided significantly (χ2 = 5.49, p < 0.05; χ2 = 6.081, p < 0.05). These findings suggest that the R-DLPFC is likely the neural substrate for improved cognitive performance elicited by 12-week physical training.

Three-dimensional infrared scanning: an enhanced approach for spatial registration of probes for neuroimaging

Significance

Accurate spatial registration of probes (e.g., optodes and electrodes) for measurement of brain activity is a crucial aspect in many neuroimaging modalities. It may increase measurement precision and enable the transition from channel-based calculations to volumetric representations.

Aim

This technical note evaluates the efficacy of a commercially available infrared three-dimensional (3D) scanner under actual experimental (or clinical) conditions and provides guidelines for its use.

Method

We registered probe positions using an infrared 3D scanner and validated them against magnetic resonance imaging (MRI) scans on five volunteer participants.

Results

Our analysis showed that with standard cap fixation, the average Euclidean distance of probe position among subjects could reach up to 43 mm, with an average distance of 15.25 mm [standard deviation (SD) = 8.0]. By contrast, the average distance between the infrared 3D scanner and the MRI-acquired positions was 5.69 mm (SD = 1.73), while the average difference between consecutive infrared 3D scans was 3.43 mm (SD = 1.62). The inter-optode distance, which was fixed at 30 mm, was measured as 29.28 mm (SD = 1.12) on the MRI and 29.43 mm (SD = 1.96) on infrared 3D scans. Our results demonstrate the high accuracy and reproducibility of the proposed spatial registration method, making it suitable for both functional near-infrared spectroscopy and electroencephalogram studies.

Conclusions

The 3D infrared scanning technique for spatial registration of probes provides economic efficiency, simplicity, practicality, repeatability, and high accuracy, with potential benefits for a range of neuroimaging applications. We provide practical guidance on anonymization, labeling, and post-processing of acquired scans.