Regionally Specific Regulation of Sensorimotor Network Connectivity Following Tactile Improvement

Correlations between inherent, task-free low-frequency fluctuations in the blood oxygenation level-dependent (BOLD) signals of the brain provide a potent tool to delineate its functional architecture in terms of intrinsic functional connectivity (iFC). Still, it remains unclear how iFC is modulated during learning. We employed whole-brain resting-state magnetic resonance imaging prior to and after training-independent repetitive sensory stimulation (rSS), which is known to induce somatosensory cortical reorganization. We investigated which areas in the sensorimotor network are susceptible to neural plasticity (i.e., where changes in functional connectivity occurred) and where iFC might be indicative of enhanced tactile performance. We hypothesized iFC to increase in those brain regions primarily receiving the afferent tactile input. Strengthened intrinsic connectivity within the sensorimotor network after rSS was found not only in the postcentral gyrus contralateral to the stimulated hand, but also in associative brain regions, where iFC correlated positively with tactile performance or learning. We also observed that rSS led to attenuation of the network at higher cortical levels, which possibly promotes facilitation of tactile discrimination. We found that resting-state BOLD fluctuations are linked to behavioral performance and sensory learning, indicating that network fluctuations at rest are predictive of behavioral changes and neuroplasticity.

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Resting state functional connectivity in the human spinal cord

eLife ◽

10.7554/elife.02812 ◽

2014 ◽

Vol 3 ◽

Cited By ~ 53

Author(s):

Robert L Barry ◽

Seth A Smith ◽

Adrienne N Dula ◽

John C Gore

Keyword(s):

Spinal Cord ◽

Functional Connectivity ◽

Resting State ◽

Low Frequency ◽

Blood Oxygenation ◽

Resting State Functional Connectivity ◽

Human Spinal Cord ◽

Oxygenation Level ◽

Left And Right ◽

The Brain

Functional magnetic resonance imaging using blood oxygenation level dependent (BOLD) contrast is well established as one of the most powerful methods for mapping human brain function. Numerous studies have measured how low-frequency BOLD signal fluctuations from the brain are correlated between voxels in a resting state, and have exploited these signals to infer functional connectivity within specific neural circuits. However, to date there have been no previous substantiated reports of resting state correlations in the spinal cord. In a cohort of healthy volunteers, we observed robust functional connectivity between left and right ventral (motor) horns, and between left and right dorsal (sensory) horns. Our results demonstrate that low-frequency BOLD fluctuations are inherent in the spinal cord as well as the brain, and by analogy to cortical circuits, we hypothesize that these correlations may offer insight into the execution and maintenance of sensory and motor functions both locally and within the cerebrum.

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Dynamic Brain-Body Coupling of Breath-by-Breath O2-CO2 Exchange Ratio with Resting State Cerebral Hemodynamic Fluctuations

10.1101/843482 ◽

2019 ◽

Author(s):

Suk-tak Chan ◽

Karleyton C. Evans ◽

Tian-yue Song ◽

Juliette Selb ◽

Andre van der Kouwe ◽

...

Keyword(s):

Resting State ◽

Strong Correlation ◽

Spontaneous Breathing ◽

Cerebral Blood Flow Velocity ◽

Cerebral Arteries ◽

Transcranial Doppler Sonography ◽

Low Frequency ◽

Brain Regions ◽

Blood Oxygenation ◽

Cerebral Hemodynamic

ABSTRACTThe origin of low frequency cerebral hemodynamic fluctuations (CHF) in resting state remains unknown. Here we studied the contribution of respiratory gas exchange (RGE) metrics to CHF during spontaneous breathing. RGE metrics include the breath-by-breath changes of partial pressure of oxygen (ΔPO2) and carbon dioxide (ΔPCO2) between end inspiration and end expiration, and their ratio breath-by-breath O2-CO2 exchange ratio (bER). We used transcranial Doppler sonography to evaluate CHF changes during spontaneous breathing by measuring the cerebral blood flow velocity (CBFv) in the middle cerebral arteries. The regional CHF changes during spontaneous breathing were mapped with blood oxygenation level dependent (BOLD) signal changes using functional magnetic resonance imaging (fMRI) technique. We found that prominent oscillations with periods of 0.5 to 2 minutes characterized ΔPO2, ΔPCO2 and bER. The oscillations of bER were coherent with CHF during spontaneous breathing at the frequency range of 0.008-0.03Hz which is consistent with the low frequency resting state CHF. CHF had strong correlation with bER, followed by ΔPO2 and then by ΔPCO2. Brain regions with the strongest bER-CHF coupling overlapped with many areas of default mode network. Although the physiological mechanisms underlying the strong correlation between bER and CHF are not completely understood, our findings suggest the contribution of bER to low frequency resting state CHF. It also provides a novel insight of brain-body interaction via CHF and oscillations of RGE metrics.

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Impaired Effective Functional Connectivity of the Sensorimotor Network in Interictal Episodic Migraineurs Without Aura

10.21203/rs.3.rs-39331/v1 ◽

2020 ◽

Author(s):

Heng-Le Wei ◽

Jing Chen ◽

Yu-Chen Chen ◽

Yu-Sheng Yu ◽

Xi Guo ◽

...

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Brain Regions ◽

Angular Gyrus ◽

Middle Temporal Gyrus ◽

Causality Analysis ◽

Imaging Data ◽

Sensorimotor Network ◽

The Right ◽

The Impact

Abstract Background: Resting-state functional magnetic resonance imaging (Rs-fMRI) has confirmed sensorimotor network (SMN) dysfunction in migraine without aura (MwoA). However, the underlying mechanisms of SMN causal functional connectivity in MwoA remain unclear. We aimed to explore the association between clinical characteristics and effective functional connectivity in SMN, in interictal patients who have MwoA.Methods: We used Rs-fMRI to acquire imaging data in forty episodic patients with MwoA in the interictal phase and thirty-four healthy controls (HCs). Independent component analysis was used to profile the distribution of SMN and calculate the different SMN activity between the two groups. Subsequently, Granger causality analysis was used to analyze the effective causal connectivity between the SMN and other brain regions.Results: Compared to the HCs, MwoA patients showed higher activity in the bilateral postcentral gyri (PoCG) and supplementary motor areas, but lower activity in left Rolandic operculum/insula. Moreover, MwoA patients showed significantly causal connectivity from the SMN to the left calcarine sulcus, left middle temporal gyrus, right angular gyrus and right precuneus. There was also significant causal connectivity from the left calcarine sulcus, left inferior orbitofrontal cortex, right cuneus, right putamen and left inferior parietal lobule to the SMN. In the interictal period, there was positive correlation between the activity of the left PoCG and headache frequency (r = 0.410, p = 0.013), but negative correlation between the activity of the right PoCG and the impact of headache (r = -0.397, p = 0.016). In addition, the disease duration was directly proportional to the connectivity strength from the left PoCG to the right angular gyrus (r = 0.418, p = 0.011), and from the right PoCG to the left calcarine sulcus (r = 0.377, p = 0.023).Conclusions: These differential, resting-state functional activities of the SMN in episodic MwoA may contribute to the understanding of migraine-related intra- and internetwork imbalances associated with nociceptive regulation and chronification.

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Task-evoked Negative BOLD Response and Functional Connectivity in the Default Mode Network are Representative of Two Overlapping but Separate Neurophysiological Processes

Scientific Reports ◽

10.1038/s41598-019-50483-8 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

David B. Parker ◽

Qolamreza R. Razlighi

Keyword(s):

Functional Connectivity ◽

Default Mode Network ◽

Resting State ◽

Low Frequency ◽

Brain Regions ◽

Intrinsic Activity ◽

Bold Response ◽

Default Mode ◽

Macro Scale ◽

Negative Bold

Abstract The topography of the default mode network (DMN) can be obtained with one of two different functional magnetic resonance imaging (fMRI) methods: either from the spontaneous but organized synchrony of the low-frequency fluctuations in resting-state fMRI (rs-fMRI), known as “functional connectivity”, or from the consistent and robust deactivations in task-based fMRI (tb-fMRI), here referred to as the “negative BOLD response” (NBR). These two methods are fundamentally different, but their results are often used interchangeably to describe the brain’s resting-state, baseline, or intrinsic activity. While the DMN was initially defined by consistent task-based decreases in blood flow in a set of specific brain regions using PET imaging, recently nearly all studies on the DMN employ functional connectivity in rs-fMRI. In this study, we first show the high level of spatial overlap between NBR and functional connectivity of the DMN extracted from the same tb-fMRI scan; then, we demonstrate that the NBR in putative DMN regions can be significantly altered without causing any change in their overlapping functional connectivity. Furthermore, we present evidence that in the DMN, the NBR is more closely related to task performance than the functional connectivity. We conclude that the NBR and functional connectivity of the DMN reflect two separate but overlapping neurophysiological processes, and thus should be differentiated in studies investigating brain-behavior relationships in both healthy and diseased populations. Our findings further raise the possibility that the macro-scale networks of the human brain might internally exhibit a hierarchical functional architecture.

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Resting-state functional connectivity modulates the BOLD activation induced by nucleus accumbens stimulation in the swine brain

10.1101/571513 ◽

2019 ◽

Author(s):

Shinho Cho ◽

Jan T. Hachmann ◽

Irena Balzekas ◽

Myung-Ho In ◽

Lindsey G. Andres-Beck ◽

...

Keyword(s):

Nucleus Accumbens ◽

Functional Connectivity ◽

Resting State ◽

Large Scale ◽

Brain Regions ◽

Blood Oxygenation ◽

Functional Networks ◽

Swine Model ◽

Resting State Functional Connectivity ◽

The Impact

ABSTRACTWhile it is known that the clinical efficacy of deep brain stimulation (DBS) alleviates motor-related symptoms, cognitive and behavioral effects of DBS and its action mechanism on brain circuits are not clearly understood. By combining functional magnetic resonance imaging (fMRI) and DBS, we investigated the pattern of blood-oxygenation-level-dependent (BOLD) signal changes induced by stimulating the nucleus accumbens and how inter-regional resting-state functional connectivity is related with the stimulation DBS effect in a healthy swine model. We found that the pattern of stimulation-induced BOLD activation was diffused across multiple functional networks including the prefrontal, limbic, and thalamic regions, altering inter-regional functional connectivity after stimulation. Furthermore, our results showed that the strength of the DBS effect is closely related to the strength of inter-regional resting-state functional connectivity including stimulation locus and remote brain regions. Our results reveal the impact of nucleus accumbens stimulation on major functional networks, highlighting functional connectivity may mediate the modulation effect of DBS via large-scale brain networks.

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Impaired effective functional connectivity of the sensorimotor network in interictal episodic migraineurs without aura

10.21203/rs.3.rs-39331/v2 ◽

2020 ◽

Author(s):

Heng-Le Wei ◽

Jing Chen ◽

Yu-Chen Chen ◽

Yu-Sheng Yu ◽

Xi Guo ◽

...

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Brain Regions ◽

Middle Temporal Gyrus ◽

Causality Analysis ◽

Imaging Data ◽

Sensorimotor Network ◽

Midcingulate Cortex ◽

Underlying Mechanisms ◽

The Right

Abstract Background: Resting-state functional magnetic resonance imaging (Rs-fMRI) has confirmed sensorimotor network (SMN) dysfunction in migraine without aura (MwoA). However, the underlying mechanisms of SMN effective functional connectivity in MwoA remain unclear. We aimed to explore the association between clinical characteristics and effective functional connectivity in SMN, in interictal patients who have MwoA. Methods : We used Rs-fMRI to acquire imaging data in forty episodic patients with MwoA in the interictal phase and thirty-four healthy controls (HCs). Independent component analysis was used to profile the distribution of SMN and calculate the different SMN activity between the two groups. Subsequently, Granger causality analysis was used to analyze the effective functional connectivity between the SMN and other brain regions. Results: Compared to the HCs, MwoA patients showed higher activity in the bilateral postcentral gyri (PoCG), but lower activity in the left midcingulate cortex (MCC). Moreover, MwoA patients showed decreased effective functional connectivity from the SMN to left middle temporal gyrus, right putamen, left insula and bilateral precuneus, but increased effective functional connectivity to the right paracentral lobule. There was also significant effective functional connectivity from the primary visual cortex, right cuneus and right putamen to the SMN. In the interictal period, there was positive correlation between the activity of the right PoCG and the frequency of headache. The disease duration was positively correlated with abnormal effective functional connectivity from the left PoCG to right precuneus. In addition, the headache impact scores were negatively correlated with abnormal effective functional connectivity from the left MCC to right paracentral lobule, as well as from the right precuneus to left PoCG. Conclusions: These differential, resting-state functional activities of the SMN in episodic MwoA may contribute to the understanding of migraine-related intra- and internetwork imbalances associated with nociceptive regulation and chronification.

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Impaired effective functional connectivity of the sensorimotor network in interictal episodic migraineurs without aura

The Journal of Headache and Pain ◽

10.1186/s10194-020-01176-5 ◽

2020 ◽

Vol 21 (1) ◽

Cited By ~ 2

Author(s):

Heng-Le Wei ◽

Jing Chen ◽

Yu-Chen Chen ◽

Yu-Sheng Yu ◽

Xi Guo ◽

...

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Brain Regions ◽

Middle Temporal Gyrus ◽

Causality Analysis ◽

Imaging Data ◽

Sensorimotor Network ◽

Midcingulate Cortex ◽

Underlying Mechanisms ◽

The Right

Abstract Background Resting-state functional magnetic resonance imaging (Rs-fMRI) has confirmed sensorimotor network (SMN) dysfunction in migraine without aura (MwoA). However, the underlying mechanisms of SMN effective functional connectivity in MwoA remain unclear. We aimed to explore the association between clinical characteristics and effective functional connectivity in SMN, in interictal patients who have MwoA. Methods We used Rs-fMRI to acquire imaging data in 40 episodic patients with MwoA in the interictal phase and 34 healthy controls (HCs). Independent component analysis was used to profile the distribution of SMN and calculate the different SMN activity between the two groups. Subsequently, Granger causality analysis was used to analyze the effective functional connectivity between the SMN and other brain regions. Results Compared to the HCs, MwoA patients showed higher activity in the bilateral postcentral gyri (PoCG), but lower activity in the left midcingulate cortex (MCC). Moreover, MwoA patients showed decreased effective functional connectivity from the SMN to left middle temporal gyrus, right putamen, left insula and bilateral precuneus, but increased effective functional connectivity to the right paracentral lobule. There was also significant effective functional connectivity from the primary visual cortex, right cuneus and right putamen to the SMN. In the interictal period, there was positive correlation between the activity of the right PoCG and the frequency of headache. The disease duration was positively correlated with abnormal effective functional connectivity from the left PoCG to right precuneus. In addition, the headache impact scores were negatively correlated with abnormal effective functional connectivity from the left MCC to right paracentral lobule, as well as from the right precuneus to left PoCG. Conclusions These differential, resting-state functional activities of the SMN in episodic MwoA may contribute to the understanding of migraine-related intra- and internetwork imbalances associated with nociceptive regulation and chronification.

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Brain functional connectivity in headache disorders: A narrative review of MRI investigations

Journal of Cerebral Blood Flow & Metabolism ◽

10.1177/0271678x17740794 ◽

2017 ◽

Vol 39 (4) ◽

pp. 650-669 ◽

Cited By ~ 18

Author(s):

Catherine D Chong ◽

Todd J Schwedt ◽

Anders Hougaard

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Medication Overuse Headache ◽

Headache Disorder ◽

Brain Regions ◽

Brain Network ◽

Blood Oxygenation ◽

Headache Disorders ◽

Default Mode ◽

Oxygenation Level

Resting-state functional magnetic resonance imaging (rs-fMRI) is used to interrogate the functional connectivity and network organization amongst brain regions. Functional connectivity is determined by measuring the extent of synchronization in the spontaneous fluctuations of blood oxygenation level dependent (BOLD) signal. Here, we review current rs-fMRI studies in headache disorders including migraine, trigeminal autonomic cephalalgias, and medication overuse headache. We discuss (1) brain network alterations that are shared amongst the different headache disorders and (2) network abnormalities distinct to each headache disorder. In order to focus the section on migraine, the headache disorder that has been most extensively studied, we chose to include articles that interrogated functional connectivity: (i) during the attack phase; (ii) in migraine patients with aura compared to migraine patients without aura; and (iii) of regions within limbic, sensory, motor, executive and default mode networks and those which participate in multisensory integration. The results of this review show that headache disorders are associated with atypical functional connectivity of regions associated with pain processing as well as atypical functional connectivity of multiple core resting state networks such as the salience, sensorimotor, executive, attention, limbic, visual, and default mode networks.

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The effect of congenital blindness on resting-state functional connectivity revisited

Scientific Reports ◽

10.1038/s41598-021-91976-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Maria J. S. Guerreiro ◽

Madita Linke ◽

Sunitha Lingareddy ◽

Ramesh Kekunnaya ◽

Brigitte Röder

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Visual Experience ◽

Brain Regions ◽

State Condition ◽

Resting State Functional Connectivity ◽

Congenital Blindness ◽

Eyes Closed ◽

Congenitally Blind ◽

Eyes Open

AbstractLower resting-state functional connectivity (RSFC) between ‘visual’ and non-‘visual’ neural circuits has been reported as a hallmark of congenital blindness. In sighted individuals, RSFC between visual and non-visual brain regions has been shown to increase during rest with eyes closed relative to rest with eyes open. To determine the role of visual experience on the modulation of RSFC by resting state condition—as well as to evaluate the effect of resting state condition on group differences in RSFC—, we compared RSFC between visual and somatosensory/auditory regions in congenitally blind individuals (n = 9) and sighted participants (n = 9) during eyes open and eyes closed conditions. In the sighted group, we replicated the increase of RSFC between visual and non-visual areas during rest with eyes closed relative to rest with eyes open. This was not the case in the congenitally blind group, resulting in a lower RSFC between ‘visual’ and non-‘visual’ circuits relative to sighted controls only in the eyes closed condition. These results indicate that visual experience is necessary for the modulation of RSFC by resting state condition and highlight the importance of considering whether sighted controls should be tested with eyes open or closed in studies of functional brain reorganization as a consequence of blindness.

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Neural basis underlying the trait of attachment anxiety and avoidance revealed by the amplitude of low-frequency fluctuations and resting-state functional connectivity

BMC Neuroscience ◽

10.1186/s12868-021-00617-4 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Min Deng ◽

Xing Zhang ◽

Xiaoyan Bi ◽

Chunhai Gao

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Low Frequency ◽

Cingulate Cortex ◽

Posterior Cingulate Cortex ◽

Attachment Anxiety ◽

Frequency Fluctuation ◽

Resting State Functional Connectivity ◽

Attachment Avoidance ◽

Posterior Cingulate

Abstract Background Attachment theory demonstrates that early attachment experience shapes internal working models with mental representations of self and close relationships, which affects personality traits and interpersonal relationships in adulthood. Although research has focused on brain structural and functional underpinnings to disentangle attachment styles in healthy individuals, little is known about the spontaneous brain activity associated with self-reported attachment anxiety and avoidance during the resting state. Methods One hundred and nineteen individuals participated in the study, completing the Experience in Close Relationship scale immediately after an 8-min fMRI scanning. We used the resting-state functional magnetic resonance imaging (rs-fMRI) signal of the amplitude of low-frequency fluctuation and resting-state functional connectivity to identify attachment-related regions and networks. Results Consequently, attachment anxiety is closely associated with the amplitude of low-frequency fluctuations in the right posterior cingulate cortex, over-estimating emotional intensity and exaggerating outcomes. Moreover, the functional connectivity between the posterior cingulate cortex and fusiform gyrus increases detection ability for potential threat or separation information, facilitating behavior motivation. The attachment avoidance is positively correlated with the amplitude of low-frequency fluctuation in the bilateral lingual gyrus and right postcentral and negatively correlated with the bilateral orbital frontal cortex and inferior temporal gyrus. Functional connection with attachment avoidance contains critical nodes in the medial temporal lobe memory system, frontal-parietal network, social cognition, and default mode network necessary to deactivate the attachment system and inhibit attachment-related behavior. Conclusion and implications These findings clarify the amplitude of low-frequency fluctuation and resting-state functional connectivity neural signature of attachment style, associated with attachment strategies in attachment anxiety and attachment avoidance individuals. These findings may improve our understanding of the pathophysiology of the attachment-related disorder.

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