Novel Technique for Noninvasive Detection of Localized Dynamic Brain Signals by Using Transcranial Static Magnetic Fields

Static Magnetic Fields ◽

Novel Technique ◽

Brain Signals ◽

Conventional techniques for noninvasive measurement of brain function such as electroencephalography (EEG), magnetoencephalography (MEG), functional magnetic resonance imaging (fMRI), and functional near-infrared spectroscopy (fNIRS) have critical limitations of spatial or temporal resolution. Here, we developed a novel technique which enables the precise measurement of dynamic brain signals and localized identification of active brain regions. In this technique, termed as magnetically biased field (MBF), human brain signal is measured as the fluctuation of a transcranial static magnetic field emitted by a coil placed on the scalp. The validity of MBF was confirmed by the measurement of somatosensory evoked signals. Fast somatosensory evoked signals were successfully observed. Localized maximum positive and negative deflections appeared at the region which represents the right primary somatosensory area contralateral to the stimulated hand. The ability of MBF to detect dynamic brain activity precisely can have numerous applications such as diagnosing brain diseases and brain-machine interfaces.

Novel Technique for Noninvasive Detection of Localized Dynamic Brain Signals by Using Transcranial Static Magnetic Fields

10.36227/techrxiv.12832094 ◽

2020 ◽

Author(s):

Osamu Hiwaki

Keyword(s):

Near Infrared ◽

Brain Activity ◽

Brain Regions ◽

Brain Diseases ◽

Noninvasive Detection ◽

Static Magnetic Fields ◽

Novel Technique ◽

Brain Signals ◽

Conventional techniques for noninvasive measurement of brain function such as electroencephalography (EEG), magnetoencephalography (MEG), functional magnetic resonance imaging (fMRI), and functional near-infrared spectroscopy (fNIRS) have critical limitations of spatial or temporal resolution. Here, we developed a novel technique which enables the precise measurement of dynamic brain signals and localized identification of active brain regions. In this technique, termed as magnetically biased field (MBF), human brain signal is measured as the fluctuation of a transcranial static magnetic field emitted by a coil placed on the scalp. The validity of MBF was confirmed by the measurement of somatosensory evoked signals. Fast somatosensory evoked signals were successfully observed. Localized maximum positive and negative deflections appeared at the region which represents the right primary somatosensory area contralateral to the stimulated hand. The ability of MBF to detect dynamic brain activity precisely can have numerous applications such as diagnosing brain diseases and brain-machine interfaces.

Optical Mapping of Brain Activity Underlying Directionality and Its Modulation by Expertise in Mandarin/English Interpreting

Frontiers in Human Neuroscience ◽

10.3389/fnhum.2021.649578 ◽

2021 ◽

Vol 15 ◽

Author(s):

Yan He ◽

Yinying Hu ◽

Yaxi Yang ◽

Defeng Li ◽

Yi Hu

Keyword(s):

Prefrontal Cortex ◽

Cognitive Skills ◽

Near Infrared ◽

Right Hemisphere ◽

Brain Activity ◽

Brain Regions ◽

Broca’S Area ◽

Broca's Area ◽

Recent neuroimaging research has suggested that unequal cognitive efforts exist between interpreting from language 1 (L1) to language 2 (L2) compared with interpreting from L2 to L1. However, the neural substrates that underlie this directionality effect are not yet well understood. Whether directionality is modulated by interpreting expertise also remains unknown. In this study, we recruited two groups of Mandarin (L1)/English (L2) bilingual speakers with varying levels of interpreting expertise and asked them to perform interpreting and reading tasks. Functional near-infrared spectroscopy (fNIRS) was used to collect cortical brain data for participants during each task, using 68 channels that covered the prefrontal cortex and the bilateral perisylvian regions. The interpreting-related neuroimaging data was normalized by using both L1 and L2 reading tasks, to control the function of reading and vocalization respectively. Our findings revealed the directionality effect in both groups, with forward interpreting (from L1 to L2) produced more pronounced brain activity, when normalized for reading. We also found that directionality was modulated by interpreting expertise in both normalizations. For the group with relatively high expertise, the activated brain regions included the right Broca’s area and the left premotor and supplementary motor cortex; whereas for the group with relatively low expertise, the activated brain areas covered the superior temporal gyrus, the dorsolateral prefrontal cortex (DLPFC), the Broca’s area, and visual area 3 in the right hemisphere. These findings indicated that interpreting expertise modulated brain activation, possibly because of more developed cognitive skills associated with executive functions in experienced interpreters.

Novel Technique for Noninvasive Detection of Localized Dynamic Brain Signals by Using Transcranial Static Magnetic Fields

IEEE Journal of Translational Engineering in Health and Medicine ◽

10.1109/jtehm.2020.3039043 ◽

2021 ◽

Vol 9 ◽

pp. 1-6

Author(s):

Osamu Hiwaki

Keyword(s):

Magnetic Fields ◽

Noninvasive Detection ◽

Static Magnetic Fields ◽

Novel Technique ◽

Brain Signals

Reforming Sectarian Beliefs in Iraq: Winning the Peace

Communication Society and Media ◽

10.22158/csm.v4n1p8 ◽

2021 ◽

Vol 4 (1) ◽

pp. p8

Author(s):

Michael Oler ◽

Anthony Johnson ◽

Anna McCulloh ◽

Munqith Dagher ◽

Anita Day ◽

...

Keyword(s):

Prefrontal Cortex ◽

Neural Activity ◽

Public Perception ◽

Near Infrared ◽

Brain Regions ◽

Frontal Pole ◽

Imaging Device ◽

Neural Imaging ◽

Sectarian violence continues in Iraq affecting regional and world security. Neuroscience techniques are used to assess the mentalizing process and counter-arguing in response to videos designed to prevent extremist radicalization. Measurement of neural activity in brain Regions of Interest (ROI) assists identification of messages which can promote favorable behavior. Activation of the Medial Prefrontal Cortex (MPFC) is associated with message adoption and behavior change. Public Service Announcements (PSAs) have not been effective in reducing violence in Iraq. This study demonstrates that the four PSAs investigated in this study do not activate the MPFC. The RLPFC is a brain ROI associated with counter-arguing and message resistance. This study demonstrates that reduction in activity in the Right Lateral Prefrontal Cortex (RLPFC) is associated with decreased sectarianism. Engagement was measured and is associated with activity in the frontal pole regions.We introduce Functional Near-infrared Spectroscopy (fNIRS) to measure the neural activity of highly sectarian Iraqis in response to these anti-sectarian messages. Neural activity was measured while viewing three PSAs and a fourth unpublished video. All four videos are intended to reduce sectarianism. A novel sectarianism scale is introduced to measure sectarian beliefs before and after the messages. This sectarian scale has high internal consistency as measured by Cronbach’s alpha. Measured activation of brain ROIs are correlated with changes in the sectarian scale. Twelve Sunni and twelve Shi’a Iraqis participated in the study. Subjects were shown the four videos in randomized order, while equipped with a fNIRS neural imaging device. All four videos produced significant engagement. None of the videos reduced sectarianism nor caused brain activation of adoption. This is consistent with the widely held Iraqi public perception that the PSAs are ineffective. Only one video, which was un-published, caused reduced sectarian beliefs. This un-published fourth video was associated with decreased counter-arguing. Counter-arguing is associated with message resistance.

Affiliative bonding between teachers and students through interpersonal synchronisation in brain activity

Social Cognitive and Affective Neuroscience ◽

10.1093/scan/nsaa016 ◽

2020 ◽

Vol 15 (1) ◽

pp. 97-109 ◽

Cited By ~ 4

Author(s):

Lifen Zheng ◽

Wenda Liu ◽

Yuhang Long ◽

Yu Zhai ◽

Hui Zhao ◽

...

Keyword(s):

Social Interaction ◽

Resting State ◽

Near Infrared ◽

Brain Activity ◽

Human Beings ◽

Teacher Student ◽

Before And After ◽

A Chain ◽

Abstract Human beings organise socially. Theories have posited that interpersonal neural synchronisation might underlie the creation of affiliative bonds. Previous studies tested this hypothesis mainly during a social interaction, making it difficult to determine whether the identified synchronisation is associated with affiliative bonding or with social interaction. This study addressed this issue by focusing on the teacher–student relationship in the resting state both before and after a teaching period. Brain activity was simultaneously measured in both individuals using functional near-infrared spectroscopy. The results showed a significant increase in brain synchronisation at the right sensorimotor cortex between the teacher and student in the resting state after, but not before, the teaching period. Moreover, the synchronisation increased only after a turn-taking mode of teaching but not after a lecturing or video mode of teaching. A chain mediation analysis showed that brain synchronisation during teaching partially mediated the relationship between the brain synchronisation increase in the resting state and strength of the affiliative bond. Finally, both role assignment and social interaction were found to be required for affiliative bonding. Together, these results support the hypothesis that interpersonal synchronisation in brain activity underlies affiliative bonding and that social interaction mechanically mediates the bonding process.

Interpersonal brain synchronization under bluffing in strategic games

Social Cognitive and Affective Neuroscience ◽

10.1093/scan/nsaa154 ◽

2020 ◽

Vol 15 (12) ◽

pp. 1326-1335

Author(s):

Zhihao Wang ◽

Yiwen Wang ◽

Xiaolin Zhou ◽

Rongjun Yu

Keyword(s):

Near Infrared ◽

Brain Activity ◽

Strategic Thinking ◽

Human Condition ◽

Angular Gyrus ◽

Strategic Games ◽

High Penalty ◽

The Right ◽

The Brain

Abstract People commonly use bluffing as a strategy to manipulate other people’s beliefs about them for gain. Although bluffing is an important part of successful strategic thinking, the inter-brain mechanisms underlying bluffing remain unclear. Here, we employed a functional near-infrared spectroscopy hyperscanning technique to simultaneously record the brain activity in the right temporal-parietal junction in 32 pairs of participants when they played a bluffing game against each other or with computer opponents separately. We also manipulated the penalty for bluffing (high vs low). Under the condition of high relative to low penalty, results showed a higher bluffing rate and a higher calling rate in human-to-human as compared to human-to-computer pairing. At the neural level, high relative to low penalty condition increased the interpersonal brain synchronization (IBS) in the right angular gyrus (rAG) during human-to-human as compared to human-to-computer interaction. Importantly, bluffing relative to non-bluffing, under the high penalty and human-to-human condition, resulted in an increase in response time and enhanced IBS in the rAG. Participants who bluffed more frequently also elicited stronger IBS. Our findings support the view that regions associated with mentalizing become synchronized during bluffing games, especially under the high penalty and human-to-human condition.

Subdividing Stress Groups into Eustress and Distress Groups Using Laterality Index Calculated from Brain Hemodynamic Response

Biosensors ◽

10.3390/bios12010033 ◽

2022 ◽

Vol 12 (1) ◽

pp. 33

Author(s):

SuJin Bak ◽

Jaeyoung Shin ◽

Jichai Jeong

Keyword(s):

Cognitive Abilities ◽

Near Infrared ◽

Brain Activity ◽

High Stress ◽

Stress Group ◽

Stimulus Response ◽

Laterality Index ◽

Target Effect ◽

A stress group should be subdivided into eustress (low-stress) and distress (high-stress) groups to better evaluate personal cognitive abilities and mental/physical health. However, it is challenging because of the inconsistent pattern in brain activation. We aimed to ascertain the necessity of subdividing the stress groups. The stress group was screened by salivary alpha-amylase (sAA) and then, the brain’s hemodynamic reactions were measured by functional near-infrared spectroscopy (fNIRS) based on the near-infrared biosensor. We compared the two stress subgroups categorized by sAA using a newly designed emotional stimulus-response paradigm with an international affective picture system (IAPS) to enhance hemodynamic signals induced by the target effect. We calculated the laterality index for stress (LIS) from the measured signals to identify the dominantly activated cortex in both the subgroups. Both the stress groups exhibited brain activity in the right frontal cortex. Specifically, the eustress group exhibited the largest brain activity, whereas the distress group exhibited recessive brain activity, regardless of positive or negative stimuli. LIS values were larger in the order of the eustress, control, and distress groups; this indicates that the stress group can be divided into eustress and distress groups. We built a foundation for subdividing stress groups into eustress and distress groups using fNIRS.

Brain regions and functional interactions supporting early word recognition in the face of input variability

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1617589114 ◽

2017 ◽

Vol 114 (29) ◽

pp. 7588-7593 ◽

Cited By ~ 6

Author(s):

Silvia Benavides-Varela ◽

Roma Siugzdaite ◽

David Maximiliano Gómez ◽

Francesco Macagno ◽

Luigi Cattarossi ◽

...

Keyword(s):

Near Infrared ◽

Brain Regions ◽

Test Phase ◽

Frontal Region ◽

Functional Connections ◽

The Face ◽

The Right ◽

Everyday Learning ◽

Open Question

Perception and cognition in infants have been traditionally investigated using habituation paradigms, assuming that babies’ memories in laboratory contexts are best constructed after numerous repetitions of the very same stimulus in the absence of interference. A crucial, yet open, question regards how babies deal with stimuli experienced in a fashion similar to everyday learning situations—namely, in the presence of interfering stimuli. To address this question, we used functional near-infrared spectroscopy to test 40 healthy newborns on their ability to encode words presented in concomitance with other words. The results evidenced a habituation-like hemodynamic response during encoding in the left-frontal region, which was associated with a progressive decrement of the functional connections between this region and the left-temporal, right-temporal, and right-parietal regions. In a recognition test phase, a characteristic neural signature of recognition recruited first the right-frontal region and subsequently the right-parietal ones. Connections originating from the right-temporal regions to these areas emerged when newborns listened to the familiar word in the test phase. These findings suggest a neural specialization at birth characterized by the lateralization of memory functions: the interplay between temporal and left-frontal regions during encoding and between temporo-parietal and right-frontal regions during recognition of speech sounds. Most critically, the results show that newborns are capable of retaining the sound of specific words despite hearing other stimuli during encoding. Thus, habituation designs that include various items may be as effective for studying early memory as repeated presentation of a single word.

Prefrontal Hemodynamic Changes Associated with Subjective Sense of Occlusal Discomfort

BioMed Research International ◽

10.1155/2015/395705 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Yumie Ono ◽

Goh Kobayashi ◽

Rika Hayama ◽

Ryuhei Ikuta ◽

Minoru Onozouka ◽

...

Keyword(s):

Near Infrared ◽

Brain Activity ◽

Self Regulation ◽

Hemodynamic Responses ◽

Cerebral Activation ◽

Somatosensory Input ◽

Dorsolateral Prefrontal ◽

The Right ◽

Prefrontal Cortices

We used functional near-infrared spectroscopy to measure prefrontal brain activity accompanying the physical sensation of oral discomfort that arose when healthy young-adult volunteers performed a grinding motion with mild occlusal elevation (96 μm). We simultaneously evaluated various forms of occlusal discomfort using the visual analogue scale (VAS) and hemodynamic responses to identify the specific prefrontal activity that occurs with increased occlusal discomfort. The Oxy-Hb responses of selected channels in the bilateral frontopolar and dorsolateral prefrontal cortices increased in participants who reported increased severity of occlusal discomfort, while they decreased in those who reported no change or decreased occlusal discomfort during grinding. Moreover, the cumulative values of Oxy-Hb response in some of these channels were statistically significant predictive factors for the VAS scores. A generalized linear model analysis of Oxy-Hb signals in a group of participants who reported increased discomfort further indicated significant cerebral activation in the right frontopolar and dorsolateral prefrontal cortices that overlapped with the results of correlation analyses. Our results suggest that the increased hemodynamic responses in the prefrontal area reflect the top-down control of attention and/or self-regulation against the uncomfortable somatosensory input, which could be a possible marker to detect the subjective sense of occlusal discomfort.