scholarly journals Altered Temporal Dynamic Intrinsic Brain Activity in Late Blindness

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Xin Huang ◽  
Zhi Wen ◽  
Chen-Xing Qi ◽  
Yan Tong ◽  
Han-Dong Dan ◽  
...  
Keyword(s):  
Visual Processing ◽  
Brain Activity ◽  
Gaussian Random Field ◽  
Low Frequency ◽  
Sliding Window ◽  
Crossmodal Plasticity ◽  
The Difference ◽  
Structural Architecture ◽  
The Right ◽  
Intrinsic Brain Activity

Previous neuroimaging studies demonstrated that visual deprivation triggers significant crossmodal plasticity in the functional and structural architecture of the brain. However, prior neuroimaging studies focused on the static brain activity in blindness. It remains unknown whether alterations of dynamic intrinsic brain activity occur in late blindness (LB). This study investigated dynamic intrinsic brain activity changes in individuals with late blindness by assessing the dynamic amplitude of low-frequency fluctuations (dALFFs) using sliding-window analyses. Forty-one cases of late blindness (LB) (29 males and 12 females, mean age: 39.70±12.66 years) and 48 sighted controls (SCs) (17 males and 31 females, mean age: 43.23±13.40 years) closely matched in age, sex, and education level were enrolled in this study. The dALFF with sliding-window analyses was used to compare the difference in dynamic intrinsic brain activity between the two groups. Compared with SCs, individuals with LB exhibited significantly lower dALFF values in the bilateral lingual gyrus (LING)/calcarine (CAL) and left thalamus (THA). LB cases also showed considerably decreased dFC values between the bilateral LING/CAL and the left middle frontal gyrus (MFG) and between the left THA and the right LING/cerebelum_6 (CER) (two-tailed, voxel-level P<0.01, Gaussian random field (GRF) correction, cluster-level P<0.05). Our study demonstrated that LB individuals showed lower-temporal variability of dALFF in the visual cortices and thalamus, suggesting lower flexibility of visual thalamocortical activity, which might reflect impaired visual processing in LB individuals. These findings indicate that abnormal dynamic intrinsic brain activity might be involved in the neurophysiological mechanisms of LB.

scholarly journals Atypical Antipsychotics Mediate Dynamics of Intrinsic Brain Activity in Early-Stage Schizophrenia? A Preliminary Study

2021 ◽  
Vol 18 (12) ◽  
pp. 1205-1212
Author(s):  
Yingchan Wang ◽  
Yuchao Jiang ◽  
Dengtang Liu ◽  
Jianye Zhang ◽  
Dezhong Yao ◽  
...  
Keyword(s):  
Negative Symptoms ◽  
Atypical Antipsychotics ◽  
Early Stage ◽  
Brain Activity ◽  
Low Frequency ◽  
Antipsychotic Treatment ◽  
Before And After ◽  
Middle Occipital Gyrus ◽  
The Right ◽  
Intrinsic Brain Activity

Objective Abnormalities of static brain activity have been reported in schizophrenia, but it remains to be clarified the temporal variability of intrinsic brain activities in schizophrenia and how atypical antipsychotics affect it.Methods We employed a resting-state functional magnetic resonance imaging (rs-fMRI) and a sliding-window analysis of dynamic amplitude of low-frequency fluctuation (dALFF) to evaluate the dynamic brain activities in schizophrenia (SZ) patients before and after 8-week antipsychotic treatment. Twenty-six schizophrenia individuals and 26 matched healthy controls (HC) were included in this study.Results Compared with HC, SZ showed stronger dALFF in the right inferior temporal gyrus (ITG.R) at baseline. After medication, the SZ group exhibited reduced dALFF in the right middle occipital gyrus (MOG.R) and increased dALFF in the left superior frontal gyrus (SFG.L), right middle frontal gyrus (MFG.R), and right inferior parietal lobule (IPL.R). Dynamic ALFF in IPL.R was found to significant negative correlate with the Scale for the Assessment of Negative Symptoms (SANS) scores at baseline.Conclusion Our results showed dynamic intrinsic brain activities altered in schizophrenia after short term antipsychotic treatment. The findings of this study support and expand the application of dALFF method in the study of the pathological mechanism in psychosis in the future.

scholarly journals Dynamic Changes of Amplitude of Low-Frequency Fluctuations in Patients With Diabetic Retinopathy

2021 ◽  
Vol 12 ◽  
Author(s):  
Xin Huang ◽  
Zhi Wen ◽  
Chen-Xing Qi ◽  
Yan Tong ◽  
Yin Shen
Keyword(s):  
Diabetic Retinopathy ◽  
Brain Activity ◽  
Memory Function ◽  
Low Frequency ◽  
Parahippocampal Gyrus ◽  
Cerebral Activity ◽  
Visual Cortices ◽  
Middle Occipital Gyrus ◽  
The Right ◽  
Intrinsic Brain Activity

Background: Growing evidence demonstrate that diabetic retinopathy (DR) patients have a high risk of cognitive decline and exhibit abnormal brain activity. However, neuroimaging studies thus far have focused on static cerebral activity changes in DR patients. The characteristics of dynamic cerebral activity in patients with DR are poorly understood.Purpose: The purpose of the study was to investigate the dynamic cerebral activity changes in patients with DR using the dynamic amplitude of low-frequency fluctuation (dALFF) method.Materials and methods: Thirty-four DR patients (18 men and 16 women) and 38 healthy controls (HCs) (18 males and 20 females) closely matched in age, sex, and education were enrolled in this study. The dALFF method was used to investigate dynamic intrinsic brain activity differences between the DR and HC groups.Results: Compared with HCs, DR patients exhibited increased dALFF variability in the right brainstem, left cerebellum_8, left cerebellum_9, and left parahippocampal gyrus. In contrast, DR patients exhibited decreased dALFF variability in the left middle occipital gyrus and right middle occipital gyrus.Conclusion: Our study highlighted that DR patients showed abnormal variability of dALFF in the visual cortices, cerebellum, and parahippocampal gyrus. These findings suggest impaired visual and motor and memory function in DR individuals. Thus, abnormal dynamic spontaneous brain activity might be involved in the pathophysiology of DR.

scholarly journals Dynamic Altered Amplitude of Low-Frequency Fluctuations in Patients With Major Depressive Disorder

2021 ◽  
Vol 12 ◽  
Author(s):  
Ruiping Zheng ◽  
Yuan Chen ◽  
Yu Jiang ◽  
Mengmeng Wen ◽  
Bingqian Zhou ◽  
...  
Keyword(s):  
Major Depressive Disorder ◽  
Neural Activity ◽  
Temporal Variability ◽  
Brain Activity ◽  
Low Frequency ◽  
First Episode ◽  
Posterior Lobe ◽  
Major Depressive ◽  
Drug Naïve ◽  
The Right

Background: Major depressive disorder (MDD) has demonstrated abnormalities of static intrinsic brain activity measured by amplitude of low-frequency fluctuation (ALFF). Recent studies regarding the resting-state functional magnetic resonance imaging (rs-fMRI) have found the brain activity is inherently dynamic over time. Little is known, however, regarding the temporal dynamics of local neural activity in MDD. Here, we investigated whether temporal dynamic changes in spontaneous neural activity are influenced by MDD.Methods: We recruited 81 first-episode, drug-naive MDD patients and 64 age-, gender-, and education-matched healthy controls who underwent rs-fMRI. A sliding-window approach was then adopted for the estimation of dynamic ALFF (dALFF), which was used to measure time-varying brain activity and then compared between the two groups. The relationship between altered dALFF variability and clinical variables in MDD patients was also analyzed.Results: MDD patients showed increased temporal variability (dALFF) mainly focused on the bilateral thalamus, the bilateral superior frontal gyrus, the right middle frontal gyrus, the bilateral cerebellum posterior lobe, and the vermis. Furthermore, increased dALFF variability values in the right thalamus and right cerebellum posterior lobe were positively correlated with MDD symptom severity.Conclusions: The overall results suggest that altered temporal variability in corticocerebellar–thalamic–cortical circuit (CCTCC), involved in emotional, executive, and cognitive, is associated with drug-naive, first-episode MDD patients. Moreover, our study highlights the vital role of abnormal dynamic brain activity in the cerebellar hemisphere associated with CCTCC in MDD patients. These findings may provide novel insights into the pathophysiological mechanisms of MDD.

scholarly journals The Cumulative Therapeutic Effect of Acupuncture Treatment in Patients With Migraine Without Aura: Evidence From Dynamic Alterations of Intrinsic Brain Activity and Effective Connectivity Analysis

2021 ◽  
Author(s):  
Yilei Chen ◽  
Yingjie Kang ◽  
Shilei Luo ◽  
Shanshan Liu ◽  
Bo Wang ◽  
...  
Keyword(s):  
Migraine Attack ◽  
Therapeutic Effect ◽  
Migraine Without Aura ◽  
Acupuncture Treatment ◽  
Brain Activity ◽  
Effective Connectivity ◽  
Life Questionnaire ◽  
Precentral Gyrus ◽  
The Right ◽  
Intrinsic Brain Activity

Abstract Background: The underlying neurological mechanism of acupuncture treatment in migraine without aura (MwoA) remains unclear. Therefore, we explored the dynamic alterations of intrinsic brain activity and effective connectivity in patients with MwoA after acupuncture treatment.Methods:The fMRI scans were separately obtained at baseline, after the first and after the 12th acupuncture sessions in 40 patients with MwoA. The acupuncture treatments were finished within 6 weeks as twice a week. 36 matched healthy controls (HCs) were recruited and performed once fMRI scan. The dynamic amplitude of low-frequency fluctuation (dALFF) and dynamic granger causality analysis(GCA) were used to analyze the difference of different time points in patients with MwoA. The correlation analyses were performed in dALFF variability, dynamic effective connectivity (DEC) variability with clinical variables in patients with MwoA.Results:Compared with HCs, Patients with MwoA at baseline showed decreased dALFF variability in regions within rostral ventromedial medulla (RVM), the superior lobe of left cerebellum (Cerebelum_Crus1_L), the right inferior frontal gyrus, triangular part (IFGtriang.R), the right median cingulate and paracingulate gyri (DCG.R), the right precuneus (PCUN.R), and the left inferior parietal, supramarginal and angular gyri (IPL.L), increased dALFF variability only in the left inferior occipital gyrus (IOG.L). After acupuncture treatment, the decreased dALFF variability of the RVM, Cerebelum_Crus1_L , and PCUN.R progressively recovered, the RVM revealed gradually increased DEC variability to the right middle frontal gyrus (MFG.R), the left insula (INS.L), the right precentral gyrus (PreCG.R), and the right supramarginal gyrus (SMG.R). And enhanced DEC variability from the right fusiform gyrus (FFG.R) to RVM. Furthermore, the increased DEC variability were found from Cerebelum_Crus1_L to the left middle occipital gyrus (MOG.L) and the left precentral gyrus (PreCG.L), from PCUN.R to the right thalamus (THA.R). These dALFF variabilities were significantly positive correlated with frequency of migraine attack and negative correlated with disease duration at baseline, dynamic GCA coefficients were significantly positive correlated with Migraine-Specific Quality of Life Questionnaire (MSQ) score, negative correlated with frequency of migraine attack and visual analog scale (VAS) score postacupuncture treatment.Conclusions:Our results provide insight into dynamic alterations from the perspective of dynamic local brain activity and effective connectivity for the understanding mechanisms of cumulative therapeutic effect of acupuncture in patients with MwoA.Trial registration: ChiCTR, ChiCTR1900023105. Registered 11 May 2019, http://www.chictr.org.cn/showproj.aspx?proj=36959.

scholarly journals Neural correlates of the LSD experience revealed by multimodal neuroimaging

2016 ◽  
Vol 113 (17) ◽  
pp. 4853-4858 ◽  
Author(s):  
Robin L. Carhart-Harris ◽  
Suresh Muthukumaraswamy ◽  
Leor Roseman ◽  
Mendel Kaelen ◽  
Wouter Droog ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Visual Processing ◽  
Brain Activity ◽  
Blood Oxygen Level Dependent ◽  
Retrosplenial Cortex ◽  
Alpha Power ◽  
Blood Oxygen Level ◽  
Psychedelic Drugs ◽  
Cortex Cérébral ◽  
Intrinsic Brain Activity

Lysergic acid diethylamide (LSD) is the prototypical psychedelic drug, but its effects on the human brain have never been studied before with modern neuroimaging. Here, three complementary neuroimaging techniques: arterial spin labeling (ASL), blood oxygen level-dependent (BOLD) measures, and magnetoencephalography (MEG), implemented during resting state conditions, revealed marked changes in brain activity after LSD that correlated strongly with its characteristic psychological effects. Increased visual cortex cerebral blood flow (CBF), decreased visual cortex alpha power, and a greatly expanded primary visual cortex (V1) functional connectivity profile correlated strongly with ratings of visual hallucinations, implying that intrinsic brain activity exerts greater influence on visual processing in the psychedelic state, thereby defining its hallucinatory quality. LSD’s marked effects on the visual cortex did not significantly correlate with the drug’s other characteristic effects on consciousness, however. Rather, decreased connectivity between the parahippocampus and retrosplenial cortex (RSC) correlated strongly with ratings of “ego-dissolution” and “altered meaning,” implying the importance of this particular circuit for the maintenance of “self” or “ego” and its processing of “meaning.” Strong relationships were also found between the different imaging metrics, enabling firmer inferences to be made about their functional significance. This uniquely comprehensive examination of the LSD state represents an important advance in scientific research with psychedelic drugs at a time of growing interest in their scientific and therapeutic value. The present results contribute important new insights into the characteristic hallucinatory and consciousness-altering properties of psychedelics that inform on how they can model certain pathological states and potentially treat others.

Dissociating early and late visual processing via the Ebbinghaus illusion

2016 ◽  
Vol 33 ◽  
Author(s):  
FILIPP SCHMIDT ◽  
ANDREAS WEBER ◽  
ANKE HABERKAMP
Keyword(s):  
Visual Processing ◽  
High Frequency ◽  
Time Course ◽  
Temporal Dynamics ◽  
Low Frequency ◽  
Response Speed ◽  
Ebbinghaus Illusion ◽  
Priming Effects ◽  
Parvocellular Pathway ◽  
The Difference

AbstractVisual perception is not instantaneous; the perceptual representation of our environment builds up over time. This can strongly affect our responses to visual stimuli. Here, we study the temporal dynamics of visual processing by analyzing the time course of priming effects induced by the well-known Ebbinghaus illusion. In slower responses, Ebbinghaus primes produce effects in accordance with their perceptual appearance. However, in fast responses, these effects are reversed. We argue that this dissociation originates from the difference between early feedforward-mediated gist of the scene processing and later feedback-mediated more elaborate processing. Indeed, our findings are well explained by the differences between low-frequency representations mediated by the fast magnocellular pathway and high-frequency representations mediated by the slower parvocellular pathway. Our results demonstrate the potentially dramatic effect of response speed on the perception of visual illusions specifically and on our actions in response to objects in our visual environment generally.

Differences in network centrality between high and low myopia: a voxel-level degree centrality study

2020 ◽  
Vol 61 (10) ◽  
pp. 1388-1397
Author(s):  
Yi Cheng ◽  
Li Yan ◽  
Liqun Hu ◽  
Hongyun Wu ◽  
Xin Huang ◽  
...  
Keyword(s):  
Brain Activity ◽  
Inferior Frontal Gyrus ◽  
Brain Regions ◽  
Anterior Lobe ◽  
Parahippocampal Gyrus ◽  
Functional Networks ◽  
Degree Centrality ◽  
Left Caudate ◽  
The Difference ◽  
The Right

Background Previous studies have linked high myopia (HM) to brain activity, and the difference between HM and low myopia (LM) can be assessed. Purpose To study the differences in functional networks of brain activity between HM and LM by the voxel-level degree centrality (DC) method. Material and Methods Twenty-eight patients with HM (10 men, 18 women), 18 patients with LM (4 men, 14 women), and 59 healthy controls (27 men, 32 women) were enrolled in this study. The voxel-level DC method was used to assess spontaneous brain activity. Correlation analysis was used to explore the change of average DC value in different brain regions, in order to analyze differences in brain activity between HM and LM. Results DC values of the right cerebellum anterior lobe/brainstem, right parahippocampal gyrus, and left caudate in HM patients were significantly higher than those in LM patients ( P < 0.05). In contrast, DC values of the left medial frontal gyrus, right inferior frontal gyrus, left middle frontal gyrus, and left inferior parietal lobule were significantly lower in patients with HM ( P < 0.05). However, there was no correlation between behavior and average DC values in different brain regions ( P < 0.05). Conclusion Different changes in brain regions between HM and LM may indicate differences in neural mechanisms between HM and LM. DC values could be useful as biomarkers for differences in brain activity between patients with HM and LM. This study provides a new method to assess differences in functional networks of brain activity between patients with HM and LM.

scholarly journals Event-Related Potential Evidence of Enhanced Visual Processing in Auditory-Associated Cortex in Adults with Hearing Loss

2020 ◽  
Vol 25 (5) ◽  
pp. 237-248
Author(s):  
Maojin Liang ◽  
Jiahao Liu ◽  
Yuexin Cai ◽  
Fei Zhao ◽  
Suijun Chen ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Visual Processing ◽  
Event Related Potentials ◽  
Event Related Potential ◽  
Occipital Area ◽  
Mapping Analysis ◽  
Related Potentials ◽  
The Difference ◽  
The Right ◽  
Frontotemporal Area

Objective: The present study investigated the characteristics of visual processing in the auditory-associated cortex in adults with hearing loss using event-related potentials. Methods: Ten subjects with bilateral postlingual hearing loss were recruited. Ten age- and sex-matched normal-hearing subjects were included as controls. Visual (“sound” and “non-sound” photos)-evoked potentials were performed. The P170 response in the occipital area as well as N1 and N2 responses in FC3 and FC4 were analyzed. Results: Adults with hearing loss had higher P170 amplitudes, significantly higher N2 amplitudes, and shorter N2 latency in response to “sound” and “non-sound” photo stimuli at both FC3 and FC4, with the exception of the N2 amplitude which responded to “sound” photo stimuli at FC3. Further topographic mapping analysis revealed that patients had a large difference in response to “sound” and “non-sound” photos in the right frontotemporal area, starting from approximately 200 to 400 ms. Localization of source showed the difference to be located in the middle frontal gyrus region (BA10) at around 266 ms. Conclusions: The significantly stronger responses to visual stimuli indicate enhanced visual processing in the auditory-associated cortex in adults with hearing loss, which may be attributed to cortical visual reorganization involving the right frontotemporal cortex.

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