Alternation of Resting-State Functional Connectivity Between Visual Cortex and Hypothalamus in Guinea Pigs With Experimental Glucocorticoid Enhanced Myopia After the Treatment of Electroacupuncture

Excessive glucocorticoids (GC) may lead to the aggravation of several basic diseases including myopia, due to plasma hormone imbalances associated with the hypothalamic–pituitary–adrenal axis (HPAA). Electroacupuncture (EA) is an effective therapeutic method to treat many diseases, although it remains unclear whether EA at acupoints on the foot or back would be effective in treating eye diseases. It was recently found that visual cortex activity for responses to visual stimuli with spatial frequency and resting-state functional connectivity (FC) between the supramarginal gyrus and rostrolateral prefrontal cortex was significantly reduced in patients with high myopia. The present study aims to investigate the role of the alternation of resting-state FC among the bilateral visual cortex and hypothalamus in exerting anti-myopia effects of EA in GC-enhanced lens-induced myopic (LIM) guinea pigs such that the mechanisms of EA to treat GC-enhanced myopia at Shenshu (BL23) acupoints can be probed. To confirm the effects of EA, ocular parameters including axial length and GC-associated physiological parameters such as animal appearance, behavior, bodyweight, and levels of four HPAA-associated plasma hormones [free triiodothyronine (FT3), free thyroxine (FT4), estradiol (E2), and testosterone (T)] were also collected. Increased resting-state FC between the left and right visual cortex was detected in GC-enhanced lens-induced myopic guinea pigs with EA at BL23 acupoints (LIM+GC+EA) guinea pigs compared to GC-enhanced lens-induced myopic guinea pigs with EA at sham acupoints (LIM+GC+Sham) guinea pigs, as well as suppressed myopia and recovery of symptoms initially caused by overdose of GC. Recovered symptoms included improved animal appearance, behavior, bodyweight, and HPAA-associated plasma hormone levels were observed after 4 weeks of EA treatment. In contrast, the LIM+GC+Sham group showed decreased FC with elongation of axial length for myopization as compared to the control group and LIM group and exhibited a deterioration in physiological parameters including reduced body weight and balance disruption in the four measured HPAA-associated plasma hormones. Our findings suggest that EA could effectively treat GC-enhanced myopia by increasing resting-state FC between the left and right visual cortices, which may be pivotal to further understanding the application and mechanisms of EA in treating GC-enhanced myopia.

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Partial Correlation-Based Retinotopically Organized Resting-State Functional Connectivity Within and Between Areas of the Visual Cortex Reflects More Than Cortical Distance

Brain Connectivity ◽

10.1089/brain.2014.0331 ◽

2016 ◽

Vol 6 (1) ◽

pp. 57-75 ◽

Cited By ~ 13

Author(s):

Debra Ann Dawson ◽

Jack Lam ◽

Lindsay B. Lewis ◽

Felix Carbonell ◽

Janine D. Mendola ◽

...

Keyword(s):

Visual Cortex ◽

Functional Connectivity ◽

Resting State ◽

Partial Correlation ◽

Resting State Functional Connectivity

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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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Resting State Functional-Connectivity Mapping of Putative Visual Cortex in a Blind Patient

Journal of Vision ◽

10.1167/12.9.1304 ◽

2012 ◽

Vol 12 (9) ◽

pp. 1304-1304

Author(s):

E. DeYoe ◽

J. Mathis ◽

J. Ulmer ◽

W. Mueller

Keyword(s):

Visual Cortex ◽

Functional Connectivity ◽

Resting State ◽

Resting State Functional Connectivity ◽

Connectivity Mapping

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Relationships between cerebrovascular reactivity, visual-evoked functional activity, and resting-state functional connectivity in the visual cortex and basal forebrain in glaucoma

10.1109/embc46164.2021.9630904 ◽

2021 ◽

Author(s):

Russell W. Chan ◽

Ji Won Bang ◽

Vivek Trivedi ◽

Matthew C. Murphy ◽

Peiying Liu ◽

...

Keyword(s):

Visual Cortex ◽

Functional Connectivity ◽

Resting State ◽

Functional Activity ◽

Basal Forebrain ◽

Cerebrovascular Reactivity ◽

Resting State Functional Connectivity ◽

Visual Evoked

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Abstract 6: Resting-state Functional Connectivity Changes After Stroke Rehabilitation Using Closed Loop Neurofeedback

Stroke ◽

10.1161/str.46.suppl_1.6 ◽

2015 ◽

Vol 46 (suppl_1) ◽

Author(s):

Veena A Nair ◽

Brittany M Young ◽

Zack Nigogosyan ◽

Alex Remsick ◽

Sonya Weber ◽

...

Keyword(s):

Functional Connectivity ◽

Upper Extremity ◽

Resting State ◽

Primary Motor Cortex ◽

Seed Region ◽

Resting State Functional Connectivity ◽

Stroke Patients ◽

Motor Network ◽

Brain Changes ◽

Left And Right

Introduction: Brain-computer interface (BCI)-EEG is a promising intervention for improving motor function after stroke. However, brain changes following intervention on a BCI-EEG system are not yet fully understood. We examined changes in resting state functional connectivity (RSFC) MRI in the motor network defined by 6 key regions in the left and right primary motor cortex (M1), left and right supplementary motor area (SMA), and left and right premotor cortex (PMC). Additionally, we investigated brain-behavior correlation between rsFC and a battery of outcome measures including the Barthel Index (BI), the Stroke Impact Scale(SIS), and the Action Research Arm Test (ARAT). Methods: Fifteen stroke patients with persistent mild to severe upper extremity impairment following ischemic stroke received intervention using BCI-EEG and were tested before (T1) and at 2-3 weeks (T2) mid intervention. 11 of these patients were also tested a third time at 4-6 weeks at the end of intervention (T3). Eyes closed, 10 minute resting fMRI and anatomical scans were acquired on a GE 3T MRI scanner. Right hemisphere stroke patients’ scans were flipped so that as a group the lesion was in the left (L) hemisphere and the impaired limb right (R). Seed region based connectivity analyses were performed to examine changes in RSFC over time and in inter-hemispheric and intra-hemispheric connectivity, and correlations between brain changes and behavioral changes were investigated. Results: BCI-EEG intervention led to significant increase in intra-hemispheric connectivity (p = .03) from T1 to T3. Inter-hemispheric connectivity increased from T1 to T3, trending towards significance (p = .06). Significant positive correlations were observed between changes in RSFC (L.M1 and L.PMC, L.M1 and R.PMC, L.SMA and R.PMC, and R.PMC and R.SMA) and change in upper extremity BI score (p ranging from .01 to .001); changes in RSFC between L.PMC and R.PMC correlated with hand strength on the SIS (p = .03). A trend was observed between increase in RSFC (L.M1 and R.PMC) and increase in total ARAT score but this was not significant. Conclusions: Results suggest that BCI-EEG intervention facilitate changes in RSFC in the motor network in stroke patients and these changes are associated with improved outcomes.

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Continuous theta burst transcranial magnetic stimulation reduces resting state connectivity between visual areas

Journal of Neurophysiology ◽

10.1152/jn.00209.2013 ◽

2013 ◽

Vol 110 (8) ◽

pp. 1811-1821 ◽

Cited By ~ 41

Author(s):

Dobromir Rahnev ◽

Peter Kok ◽

Moniek Munneke ◽

Linda Bahdo ◽

Floris P. de Lange ◽

...

Keyword(s):

Visual Cortex ◽

Functional Connectivity ◽

Resting State ◽

Brain Activity ◽

Brain Regions ◽

Perceptual Task ◽

Target Area ◽

Resting State Functional Connectivity ◽

Early Visual Cortex ◽

Theta Burst

Continuous theta burst stimulation (cTBS) is a technique that allows for altering of brain activity. Research to date has focused on the effect of cTBS on the target area, but less is known about its effects on the resting state functional connectivity between different brain regions. We investigated this issue by applying cTBS to the occipital cortex and probing its influence in retinotopically defined regions in early visual cortex using functional MRI. We found that occipital cTBS reliably decreased the resting state functional connectivity (i.e., the correlation of spontaneous activity) between regions of the early visual cortex. In the context of a perceptual task, such an effect could mean that cTBS affects the strength of the perceptual signal, its variability, or both. We investigated this issue in a second experiment in which subjects performed a perceptual discrimination task and indicated their level of certainty on each trial. The results showed that occipital cTBS decreased both subjects' accuracy and confidence. Signal detection modeling suggested that these impairments resulted primarily from a decreased strength of the perceptual signal, with a nonsignificant trend of a decrease in signal variability. We discuss the implications of these experiments for understanding the mechanisms by which cTBS influences brain activity and perceptual processes.

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