Subjects: Psychology >> Developmental Psychology submitted time 2020-10-10
Abstract： Building robust letter-to-sound correspondences is a prerequisite for reading, and such audiovisual integration becomes progressively automatic with development. However, the neural mechanisms underlying the development of audiovisual integration for reading are largely unknown. This study used functional magnetic resonance imaging (fMRI) in a lexical decision task to investigate the changes of brain functional networks that support audiovisual integration for reading between normally developing children (9-12 years old) and adults (20-28 years old). The identified networks were further examined in children with developmental dyslexia (9-12 years old). Results revealed that adults enhanced connectivity in a prefrontal-superior temporal network relative to children, reflecting the attentional modulation to the development of audiovisual integration. Moreover, this network was disrupted in dyslexics, confirming its essential role in audiovisual integration for reading. This study, for the first time, elucidates the neural basis underlying the development of audiovisual integration for reading.
Peer Review Status:
Awaiting Review
Subjects: Psychology >> Cognitive Psychology submitted time 2020-06-17
Abstract： This study aimed to examine the brain mechanisms underlying the distinctions between automatic and controlled handwriting. Functional magnetic resonance imaging data were collected while adult participants (n = 53) performed a copying task with varying speed control demands. Network analysis showed significant differences in functional connectivity within and between the frontoparietal network (FPN), the default mode network (DMN), the dorsal attention network (DAN), the somatomotor network (SMN) and the visual network (VN) between automatic and speed-controlled handwriting irrespective of written materials, which are thought to reflect general executive control and task-relevant visuomotor operations. However, there were no differences in brain activation between automatic and controlled handwriting. These results suggest that reconfiguration of functional network architecture, rather than regional activation, underlies the dissociations between automatic and controlled handwriting. Our findings shed new light on the neural mechanisms of handwriting mastery and handwriting impairments in individuals with neurological disorders. " "
Peer Review Status:Awaiting Review
Subjects: Psychology >> Applied Psychology submitted time 2017-11-06
Lei Gao
Lijun Bai
Yuchen Zhang
Xi-jian Dai
Rana Netra
Youjiang Min
Fuqing燴hou
Honghan Gong
Ming Zhang
Yijun Liu
Abstract： Recent studies have indicated that sleep deprivation (SD) alters intrinsic low-frequency connectivity in the resting brain, mainly focusing on the default mode network (DMN) and its anticorrelated network (ACN). These networks hold key functions in segregating internally and externally directed awareness. However, far less attention has been paid to investigation of the altered amplitude of these low-frequency fluctuations (ALFF) at the whole-brain level and more importantly by what extent the sleep-deprived resting brain pattern can be reproducible and predict individual behavioral performance. The aim of this study was to characterize more clearly the influence of sleep on the whole brain level of ALFF changes and its relation with the performance of a lexical decision task in the sleep deprivation. Sixteen healthy participants underwent fMRI three times: once after a normal night of sleep in the rested wakefulness (RW) state and two following approximately 24 h of total SD separated by an interval of two weeks (SD1 and SD2). Our behavioral results showed that sleep stabilizes performance whereas two sleep deprivation even at an interval of two weeks consistently deteriorates it. Sleep deprivation attenuated the ALFF mainly in the bilateral orbitofrontal cortex (OFC), bilateral dorsolateral prefrontal cortex (DLPFC) and right inferior parietal lobule (IPL). By contrast, the enhanced ALFF emerged in the left sensorimotor cortex (SMA), visual cortex and left fusiform gyrus. Conjunction analysis of SD1 and SD2 versus the control maps and voxel-wise ICC analysis revealed that these SD induced ALFF changes showed a significantly high reliability (ICC＞0.5). Particularly, the attenuation of the right IPL presents a significant negative relation with the behavior performance and can be reproducible for two SD at an interval of two weeks. Our results suggest that ALFF is a stable measure in study of SD, and the right IPL may represent a stable biomarker that responds to sleep loss.
Peer Review Status:Awaiting Review
Subjects: Psychology >> Applied Psychology submitted time 2017-11-06
Abstract： Brain imaging efforts are being increasingly devoted to decode the functioning of the human brain. Among neuroimaging techniques, resting-state fMRI (R-fMRI) is currently expanding exponentially. Beyond the general neuroimaging analysis packages (e.g., SPM, AFNI and FSL), REST and DPARSF were developed to meet the increasing need of user-friendly toolboxes for R-fMRI data processing. To address recently identified methodological challenges of R-fMRI, we introduce the newly developed toolbox, DPABI, which was evolved from REST and DPARSF. DPABI incorporates recent research advances on head motion control and measurement standardization, thus allowing users to evaluate results using stringent control strategies. DPABI also emphasizes test-retest reliability and quality control of data processing. Furthermore, DPABI provides a user-friendly pipeline analysis toolkit for rat/monkey R-fMRI data analysis to reflect the rapid advances in animal imaging. In addition, DPABI includes preprocessing modules for task-based fMRI, voxel-based morphometry analysis, statistical analysis and results viewing. DPABI is designed to make data analysis require fewer manual operations, be less time-consuming, have a lower skill requirement, a smaller risk of inadvertent mistakes, and be more comparable across studies. We anticipate this open-source toolbox will assist novices and expert users alike and continue to support advancing R-fMRI methodology and its application to clinical translational studies.
Peer Review Status:Awaiting Review
Subjects: Psychology >> Experimental Psychology submitted time 2017-11-06
Abstract： Sharing drafts of scientific manuscripts on preprint hosting services for early exposure and pre-publication feedback is a well-accepted practice in fields such as physics, astronomy, or mathematics. The field of neuroscience, however, has yet to adopt the preprint model. A reason for this reluctance might partly be the lack of central preprint services for the field of neuroscience. To address this issue, we announce the launch of Preprints of the R-fMRI Network (PRN), a community funded preprint hosting service. PRN provides free-submission and free hosting of manuscripts for resting state functional magnetic resonance imaging (R-fMRI) and neuroscience related studies. Submissions will be peer viewed and receive feedback from readers and a panel of invited consultants of the R-fMRI Network. All manuscripts and feedback will be freely available online with citable permanent URL for open-access. The goal of PRN is to supplement the “peer reviewed” journal publication system – by more rapidly communicating the latest research achievements throughout the world. We hope PRN will help the field to embrace the preprint model and thus further accelerate R-fMRI and neuroscience related studies, eventually enhancing human mental health.
Peer Review Status:Awaiting Review
Subjects: Psychology >> Developmental Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： The integration of various emotional information from different modalities (e.g., face and voice) plays an important role in our interpersonal communication. In order to understand its brain mechanism, more and more researchers found that the interaction between facial expression and vocal emotional information begins in the early stage of perception, and the integration of emotional information content occurs in the late decision-making stage. In the early stage, the primary sensory cortex is responsible for encoding information; while in the late stage, the amygdala, temporal lobe and other advanced brain regions are responsible for cognitive evaluation. In addition, the functional coupling of oscillation activities on multiple frequency bands facilitates the integration of emotional information cross channels. Future research needs to explore whether facial expression and vocal emotional information integration is associated with emotional conflict, and whether inconsistent emotional information has advantages. Lastly, we should find out how the neural oscillations of different frequency bands promotes the integration of facial expression and vocal emotional information, so as to further understand its dynamic basis.
Subjects: Psychology >> Experimental Psychology submitted time 2017-11-06
Abstract： Various resting-state fMRI (R-fMRI) measures have been developed to characterize intrinsic brain activity. While each of these measures has gained a growing presence in the literature, questions remain regarding the common and unique aspects these indices capture. The present work provided a comprehensive examination of inter-individual variation and intra-individual temporal variation for commonly used measures, including fractional amplitude of low frequency fluctuations, regional homogeneity, voxel-mirrored homotopic connectivity, network centrality and global signal correlation. Regardless of whether examining intra-individual or inter-individual variation, we found that these definitionally distinct R-fMRI indices tend to exhibit a relatively high degree of covariation. When taken as a measure of intrinsic brain function, inter-individual differences in concordance for R-fMRI indices appeared to be stable, and negatively related to age (i.e., functional concordance among indices decreases with age). To understand the functional significance of concordance, we noted that higher concordance was generally associated with higher strengths of R-fMRI indices, regardless of whether looking through the lens of inter-individual (i.e., high vs. low concordance participants) or intra-individual (i.e., high vs. low concordance states identified via temporal dynamic analyses) differences. Finally, temporal dynamics analyses also revealed that high concordance states are characterized by increased within- and between-network functional connectivity, suggesting more general variations in network integration and segregation. The current study draws attention to questions regarding how to select an R-fMRI index for usage in a given study, as well as how to compare findings across studies that examine inter-individual or group differences using different indices. Additionally, our work suggests global neural signals exist in the brain, and their spontaneous variations over time result in fluctuations in the connectedness of brain regions.
Peer Review Status:Awaiting Review
Subjects: Biology >> Biophysics submitted time 2016-05-05
Deng, Xiaofeng
Xu, Long
Zhang, Yan
Wang, Shuo
Zhao, Yuanli
Cao, Yong
Zhang, Dong
Wang, Rong
Ye, Xun
Wu, Jun
Zhao, Jizong
Deng, Xiaofeng
Xu, Long
Zhang, Yan
Wang, Shuo
Zhao, Yuanli
Cao, Yong
Zhang, Dong
Wang, Rong
Ye, Xun
Abstract： The authors attempted to demonstrate the difference in language cortex reorganization between cerebral malformations (AVMs), cavernous malformations (CMs), and gliomas by blood oxygen level-dependent (BOLD) functional magnetic resonance imaging. Clinical and imaging data of 27 AVM patients (AVM-L group), 29 CM patients (CM-L group), and 20 glioma patients (Glioma-L group) were retrospectively reviewed, with lesions overlying the left inferior frontal gyrus (Broca area). As a control, patients with lesions involving the right inferior frontal gyrus were also enrolled, including 14 AVM patients (AVM-R group), 20 CM patients (CM-R group), and 14 glioma patients (Glioma-R group). All patients were right-handed. Lateralization indices (LI) of BOLD signal activations were calculated separately for Broca and Wernicke areas. In AVM-L group, right-sided lateralization of BOLD signals was observed in 10 patients (37.0 %), including 6 in the Broca area alone, 1 in the Wernicke area alone, and 3 in both areas. Three patients (10.3 %) of CM-L group showed right-sided lateralization in both Broca and Wernicke areas, and 1 patient (5.0 %) of Glioma-L group had right-sided lateralization in the Wernicke area alone. A significant difference of right-sided lateralization was observed between the AVM-L group and CM-L group (P = 0.018) and also between the AVM-L group and Glioma-L group (P = 0.027). No patient in AVM-R, CM-R, or Glioma-R groups showed right-sided lateralization. Language cortex reorganization may occur in AVM, CM, and glioma patients when the traditional language cortex was involved by lesions, but the potential of reorganization for CM and glioma patients seems to be insufficient compared with AVM patients.
Peer Review Status:Awaiting Review
Subjects: Psychology >> Social Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： Language impairment is a salient and one of the earliest symptoms of Autism Spectrum Disorder (ASD). Over the past decades, researchers have employed various neuroimaging techniques (e.g., functional magnetic resonance imaging, fMRI) to explore the neural markers of language impairments in individuals with ASD. Individual investigations have converged on finding differences in neural responses of language processing (e.g., word, sentence, prosody) between autistic participants and typically developing (TD) controls. Results from meta-analytic studies further indicated that the differential neural activities were stable across studies. However, the meta-analysis that focused on semantic processing in the ASD group revealed somewhat different results from the meta-analysis on language processing. In addition, the results of sub-analyses that divided language processing tasks into subtypes reported that the ASD-TD differential activation patterns were moderated by task type. The previous meta-analysis of semantic processing in ASD populations included both sentence-level and word-level semantic processing studies. Considering the differentiated underlying mechanisms of word-meaning and sentence-meaning processing, it is essential to distinguish between these two levels of semantic processing. Lexical-semantic processing ability is at the forefront of language acquisition and a known area of impairment in individuals with ASD. Previous review studies have adequately summarized the behavioral performance of individuals with ASD for semantic processing at the single word level. However, a meta-analysis to investigate the cross-study brain activation patterns of individuals with ASD during lexical-semantics processing is still missing. The current study identified 11 published journal articles that used fMRI to investigate lexical-semantic processing in individuals with ASD. Activation likelihood estimation analysis was adopted to investigate whether atypical brain activation patterns in individuals with ASD were stable across studies and how the atypical performance manifested. The results revealed that the TD group activated the left inferior frontal gyrus, the left superior frontal gyrus, the left middle temporal gyrus, and the left middle frontal gyrus, which are brain regions responsible for completing lexical-semantics processing tasks. Like the TD group, the ASD group also showed activation in typical lexical-semantics processing brain regions, such as the left inferior frontal gyrus, the left middle temporal gyrus, and the left medial frontal gyrus. At the same time, differential brain activation patterns were steadily present between the ASD and TD groups. To be more specific, no brain region was found in the ASD group-TD group subtraction analysis, while the left superior frontal gyrus was present in the TD group -ASD group subtraction analysis. This finding indicated the atypical brain activation patterns of lexical-semantics processing in individuals with ASD manifested as hypoactivation in the left superior frontal gyrus. In addition, exploratory sub-analyses suggested that the atypical brain activation patterns of adults with ASD may differ from those of children and adolescents with ASD. Adults with ASD were more likely to show enhanced activation in the visual processing areas, while children and adolescents with ASD showed reduced activation in the left middle temporal gyrus. In summary, the current meta-analysis provided evidence for the atypical brain responses to lexical-semantics processing in verbal individuals with ASD from a cross-study perspective. Their atypical brain activation activities when processing meanings of words were consistent with the "decreased frontal lobe activation" hypothesis. The current study revealed novel findings which highlighted that distinguishing between different levels of language processing can help researchers identify the corresponding neural markers of certain types of language impairments in autistic populations. Due to the limited number of included studies, the current study had some limitations, such as only including fMRI studies and not considering the task, behavior and general language skills related factors. Future studies should take age, language background, general language skills, intervention experiences, and types of semantic processing into consideration.
Subjects: Biology >> Biophysics submitted time 2016-05-12
Abstract： What is a number? The number sense hypothesis suggests that numerosity is "a primary visual property" like color, contrast, or orientation. However, exactly what attribute of a stimulus is the primary visual property and determines numbers in the number sense? To verify the invariant nature of numerosity perception, we manipulated the numbers of items connected/enclosed in arbitrary and irregular forms while controlling for low-level features (e.g., orientation, color, and size). Subjects performed discrimination, estimation, and equality judgment tasks in a wide range of presentation durations and across small and large numbers. Results consistently show that connecting/enclosing items led to robust numerosity underestimation, with the extent of underestimation increasing monotonically with the number of connected/enclosed items. In contrast, grouping based on color similarity had no effect on numerosity judgment. We propose that numbers or the primitive units counted in numerosity perception are influenced by topological invariants, such as connectivity and the inside/outside relationship. Beyond the behavioral measures, neural tuning curves to numerosity in the intraparietal sulcus were obtained using functional MRI adaptation, and the tuning curves showed that numbers represented in the intraparietal sulcus were strongly influenced by topology.
Peer Review Status:Awaiting Review
Subjects: Psychology >> Cognitive Psychology submitted time 2023-09-13
Abstract： Third-party punishment (TPP) refers to the punitive behaviors that individuals impose on violators as third parties or observers in order to uphold social norms. Many studies have provided insight into the neural mechanisms underlying TPP behavior. However, few studies have focused on the overall role of functional brain networks. This paper reviews the researches related to TPP in the past decade and summarizes the relevant theoretical models and brain networks. Based on the previous studies, we propose a cognitive neural network model of TPP, which could systematically explain and integrate the neural mechanisms behind TPP behavior. In this model, the affective and reward systems are the TPP power sources, and the cognitive system is mainly responsible for responsibility assessment as well as punishment selection. The reward network, the salient network, the default mode network and the central executive network are involved in different cognitive processing stages, respectively. The model establishes the connection between TPP behavior-related research at the psychological and the cognitive-neural level and provides a more holistic and comprehensive explanation of the mechanisms of TPP behavior. In the future, it is necessary to use meta-analysis or machine learning algorisms in order to explore third-party intervention preferences and the underlying cognitive neural mechanisms in different contextual information and more complex social contexts.
Subjects: Psychology >> Social Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： Self-face recognition reflects the process whereby someone can recognize their own face by distinguishing it from the other. Generally, people recognize self-faces faster than they do other faces, and self-face recognition can elicit enhanced brain activity compared with that of other face recognitions. Researching self-face recognition is valuable because of its close relationship with self-awareness. Recently, many studies used functional magnetic resonance imaging (fMRI) to investigate the neural basis of self-face recognition. However, there are no consistent results regarding the key brain regions involved in self-face recognition. Therefore, in the current study, a quantitative meta-analysis of fMRI studies, using activation likelihood estimation (ALE), was performed to localize the neural structures engaged in recognizing self-face. Twenty-seven studies involving 635 participants met the inclusion criteria. The meta-analysis was conducted in the standard Montreal Neurological Institute (MNI) space, and we translated results reported using Talairach coordinates into MNI coordinates. The statistical analysis of the transformed foci was validated using the Monte Carlo Simulation (1,000 permutations) with a cluster-forming voxel-level threshold at uncorrected p < 0.001 combined with cluster-size correction using family-wise error at p < 0.05. We used Mango software to project the activation coordinates onto a brain template to provide a visual representation of activation distributions. Results showed that the contrast of self-face versus other-face displayed increased activations of the right superior parietal lobule/precuneus/middle occipital gyrus, middle frontal gyrus, inferior frontal gyrus, fusiform gyrus, postcentral gyrus, insula, and left precuneus. There was no active region in the contrast of other-face versus self-face. Based on the meta-analysis results and on previous event-related potential (ERP) studies, self-face recognition may involve two levels of processing, perceptual integration processing and the accompanying process of evaluation and emotional response. In the process of recognizing self-face, the occipital gyrus, fusiform gyrus, and precuneus are involved in the perceptual integration process. The occipital cortices may be involved in the processing of self-related facial features in the early stages of face recognition. The fusiform gyrus is involved in low-level sensory processing, and it is also sensitive to the categorization of faces in terms of self versus nonself. The precuneus is recruited in the perceptual integration of self-related information. The superior parietal lobule, middle frontal gyrus, inferior frontal gyrus, and insula are mainly recruited in the evaluation and the emotional response at the middle and late stages of recognizing self-face. The superior parietal lobule and middle frontal gyrus have been shown to play an important role in the processing of evaluating self-face. Moreover, their activations reflect the influence of social and cultural factors on self-face recognition. The inferior frontal gyrus and insula are also involved in the processing of evaluating self-face. Furthermore, they play a direct role in the subjective emotional experience of viewing or evaluating self-face. In sum, the current meta-analysis reveals the neural basis of self-face recognition and suggests two levels of processing of self-face recognition (perceptual integration processing and the accompanying process of evaluation and emotional response). The current study provides support for investigating the neural mechanism of self-face recognition and, based on the limitations of previous studies, makes suggestions for future research. Future studies could use magnetoencephalography (MEG) or simultaneous EEG-fMRI to combine brain location and time course, thereby revealing the cognitive and neural mechanisms of self-face recognition. Close attention should be paid to the structural and functional connectivity of brain areas and brain networks and to the neural correlates of interoception and self-face recognition. Clinical studies should investigate abnormal neural activity in patients with self-processing impairment and explore the influence of threatening information on self-face recognition.
Subjects: Psychology >> Cognitive Psychology submitted time 2021-05-24
Abstract： Self-face recognition reflects the process whereby someone can recognize their own face by distinguishing it from the other. Activation likelihood estimation (ALE) was used to conduct a meta-analysis of studies using neuroimaging data to reveal the neural mechanism of self-face recognition. The neural basis of self-face recognition mainly involves the right superior parietal lobule/precuneus/middle occipital gyrus, middle frontal gyrus, inferior frontal gyrus, fusiform gyrus, postcentral gyrus, insula, and left precuneus. Based on the meta-analysis results and on previous event-related potential (ERP) studies, self-face recognition may involve two levels of processing, perceptual integration processing and the accompanying process of evaluation and emotional response. In the process of recognizing self-face, the occipital gyrus, fusiform gyrus, and precuneus are involved in the perceptual integration process. The superior parietal lobule, middle frontal gyrus, inferior frontal gyrus, and insula are mainly recruited in the evaluation and the emotional response at the middle and late stages of recognizing self-face. Future studies could reveal the cognitive and neural mechanisms of self-face recognition by attending closely to the structural and functional connectivity of brain areas and brain networks, exploring the neural correlates of interoception and self-face recognition, conducting clinical studies to investigate the abnormal neural activity of patients with self-processing impairment, and exploring the influence of threatening information on self-face recognition. "
Peer Review Status:Awaiting Review
Subjects: Psychology >> Social Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： Basic emotion theory is the most representative theory in the field of emotion science, which holds that human emotions are composed of a limited number of basic emotions, such as fear, anger, joy, sadness and so on. Basic emotions are evolved for fundamental life tasks, and each basic emotion has its own unique neural structure and physiological basis. Although basic emotion theories are widely accepted, there is little agreement on specific basic emotions. In recent decades, many fMRI studies have attempted to determine the unique neural structural underpinnings of each of the basic emotions, and made many important findings, such as disgust is related to the insula, sadness is related to the anterior cingulate gyrus, and the amygdala is an important limbic structure related to fear. However, recent meta-analysis studies have found that many basic emotions share many brain regions. Therefore, the theory of specific brain regions of basic emotions has been questioned and even denied. Through the discussion of the basic emotions and neural basis, as well as the latest functional magnetic resonance imaging (fMRI) study of basic emotion theory analysis found that a lot of brain imaging data have reported certain basic emotion that is associated with a particular brain regions, different stimulation induced a kind of basic emotion is stable to activate the same brain regions. But these studies also raise questions. As Barrett notes, the amygdala is involved in almost all negative emotions, like fear, anger, and surprise. Therefore, it is likely that the amygdala was just involved in regulating arousal. Instead, we believe that the reason for the inconsistencies in these studies is that humans may have only three basic emotions: joy, fear (anger), and sadness. Many of the so-called different basic emotions are actually the same basic emotion. Fear and anger may be the same basic emotions, while surprise may be the cognitive component that induces fear and anger. They share a common neural basis: the amygdala. Recently, researchers have tried to interpret the facial expressions of laboratory rats by using machine-vision technology to process their facial features. Similarly, machine vision can be used to decode human facial expressions, emotion recognition and classification. Future research can focus on multiple forms of common and unique features and connections between features (such as functional brain connections), such as behavioral, physiological, visual cortex, eye movement, facial expression, fMRI imaging, EEG topography and other data features. At the same time, we can try to prototype emotions from many angles. Thus, it is expected to form multi-angle and multi-form emotion prototype, providing new ideas and new evidence for the research of basic emotion theory.
Subjects: Biology >> Biophysics submitted time 2016-05-05
Wei, Zhengde
Yang, Nannan
Yang, Lizhuang
Wang, Ying
Han, Long
Zha, Rujing
Huang, Ruiqi
Zhou, Yifeng
Liu, Ying
Zhang, Peng
Zhang, Xiaochu
Zhang, Xiaochu
Zhang, Xiaochu
Abstract： Nicotine addiction is associated with risky behaviors and abnormalities in local brain areas related to risky decision-making such as the dorsal anterior cingulate cortex (dACC), anterior insula (AI), and thalamus. Although these brain abnormalities are anatomically separated, they may in fact belong to one neural network. However, it is unclear whether circuit-level abnormalities lead to risky decision-making in smokers. In the current study, we used task-based functional magnetic resonance imaging (fMRI) and examined resting-state functional connectivity (RSFC) to study how connectivity between the dACC, insula, and thalamus influence risky decision-making in nicotine addicts. We found that an increase in risky decision-making was associated with stronger nicotine dependence and stronger RSFC of the dACC-rAI (right AI), the dACC-thalamus, the dACC-lAI (left AI), and the rAI-lAI, but that risky decision-making was not associated with risk level-related activation. Furthermore, the severity of nicotine dependence positively correlated with RSFC of the dACC-thalamus but was not associated with risk level-related activation. Importantly, the dACC-thalamus coupling fully mediated the effect of nicotine-dependent severity on risky decision-making. These results suggest that circuit-level connectivity may be a critical neural link between risky decision-making and severity of nicotine dependence in smokers.
Peer Review Status:Awaiting Review
Subjects: Biology >> Biophysics submitted time 2016-05-15
Zhang, Shaodan
Zhang, Chun
Zhang, Shaodan
Wang, Bo
Zhu, SenHua
Xie, Yuan
Qing, Guoping
Wang, Ningli
Thomas, Ravi
Thomas, Ravi
Abstract： PURPOSE. To assess the cortical structure and cerebral blood flow changes in the brain of patients with primary open-angle glaucoma (POAG). METHODS. High-resolution anatomical magnetic resonance imaging (MRI) and arterial spin labeling (ASL)-MRI were performed in 23 POAG patients and 29 controls. Patients were further divided into early-moderate and advanced groups based on mean deviation (MD) cutoff of 12 dB. A baseline scan was obtained and repeated during visual stimulation to the central preserved visual field in the more affected eye of POAG patients and a randomly selected eye of controls. Gray matter volume (GMV) and cerebral blood flow (CBF) throughout the whole brain were compared between patients and controls. RESULTS. Compared to controls, a region with significant reduction of GMV was detected in the anterior calcarine fissure of advanced POAG patients (P < 0.001, voxels = 503, 1698 mm3). Patients with early-moderate POAG had resting CBF similar to that of controls. However, a region with marked CBF decrease was detected in the anterior calcarine fissure of advanced POAG patients (P < 0.001, voxels = 1687, 13,496 mm(3)). The region with CBF reduction in advanced POAG showed good colocalization with the region with GMV decrease in this group. Following visual stimulation, patients with advanced POAG showed significantly lower increase in CBF in the occipital lobes (P < 0.001, voxels = 112, 896 mm(3)) as compared to controls (P < 0.001, voxels = 1880, 15,040 mm(3)) and early-moderate POAG (P < 0.001, voxels = 2233, 17,864 mm(3)). CONCLUSIONS. Primary open-angle glaucoma patients demonstrate a disease severity-dependent retinotopic pattern of cortical atrophy and CBF abnormalities in the visual cortex. Cerebral blood flow may be a potential biomarker for the brain involvement in glaucoma.
Peer Review Status:Awaiting Review
Subjects: Biology >> Biophysics submitted time 2016-05-12
Abstract： The neural correlates of associative memory in healthy older adults were investigated by examining the correlation of associative memory performance with spontaneous brain oscillations. Eighty healthy older adults underwent a resting-state functional MRI and took a paired-associative learning test (PALT). Correlations between the amplitude of low-frequency fluctuations (ALFF) as well as fractional ALFF (fALFF) in the whole brain and PALT scores were calculated. We found that spontaneous activity as indexed by both ALFF and fALFF in the parahippocampal gyrus (PHG) was significantly positively correlated with associative memory performance, suggesting that the PHG plays a critical role in associative memory in older people.
Peer Review Status:Awaiting Review
Subjects: Psychology >> Applied Psychology submitted time 2017-11-06
Abstract： Although爈inear trend removing has often been implemented as a routine preprocessing step in resting-state functional magnetic resonance imaging (RS-fMRI) data analysis, the爏patial distribution爋f the magnitude of linear trend is still unclear. Further, it is interesting whether there will be any difference of the linear trend magnitude between different resting-states. For the first aim, we analyzed 5 RS-fMRI datasets from 5 different scanners (namely Beijing-Simens-3T, Cambridge-Siemens-3T, CCBD-GE750-3T, Milwaukee-GE-3T, and Oulu-GE-1.5T). One-sample t-tests on the regression coefficient (i.e., the magnitude of linear trend) were performed for each datasets. For the second aim, we used 2 datasets in each of which different states were compared, one containing eyes-open resting-state (EO-RS) vs. eyes-closed resting-state (EC-RS) and the other containing two steady-state tasks, i.e.,爎eal-time finger force feedback�RT-FFF) and sham finger force feedback (S-FFF) tasks. Paired t-tests were performed between EO-RS and EC-RS, and between RT-FFF and S-FFF. One-sample t-tests showed that the spatial pattern of linear trend of RS-fMRI time series were quite different between different manufactures. The 3T SIEMENS scanners showed positive linear trend in almost all part of the brain, while GE scanners showed primarily negative linear trend in most part of the brain. Paired t-tests showed some differences between paired conditions; differences between EO-RS and EC-RS were mainly in cuneus and eyeballs, and differences between RT-FFF and S-FFF were found in the thalamus, anterior cingulate gyrus, and right sensorimotor cortex. The current study indicated that, while the manufacturer-dependent linear trend of RS-fMRI time series were mostly scanner-related noise, the linear trend may also be physiological noise (eyeballs) or even physiologically meaningful, especially during steady-state tasks.
Peer Review Status:Awaiting Review
Subjects: Biology >> Biophysics submitted time 2016-05-12
Rao, Jia-Sheng
Zhao, Can
Liu, Zuxiang
Yang, Zhao-Yang
Li, Xiao-Guang
Ma, Manxiu
Liu, Zuxiang
Yang, Zhao-Yang
Li, Xiao-Guang
Abstract： Purpose: To investigate the longitudinal brain regional homogeneity (ReHo) changes in nonhuman primate after spinal cord injury (SCI) by resting-state functional magnetic resonance imaging (fMRI). Methods: Three adult female rhesus monkeys underwent unilateral thoracic cord injury. A resting-state fMRI examination was performed in the healthy stage and 4, 8, and 12 weeks after the injury. The ReHo value of each voxel in the monkey brain was calculated and compared between pre- and post-SCI monkeys with paired t test. The regions of interest (ROIs) in the significantly changed ReHo regions were set. The correlations between the ReHo change and the time after injury were also determined. Results: Compared with those in healthy period, the ReHo values of the left premotor cortex and the anterior cingulate cortex (ACC) in post-SCI rhesus monkeys significantly increased in 4-week follow-up examinations. The ReHo values of posterior cingulate cortex, left precuneus, left temporal parietooccipital area, and bilateral superior parietal lobules decreased at 8-week follow-up examinations. In 12-week follow-up examinations, the ReHo values of the left postcentral gyrus, right caudate nucleus, and superior temporal gyrus increased. Correlation analysis showed positive correlations between left ACC and the postoperative time. Conclusion: SCI can change the regional synchronism of brain activity in sensorimotor system and the default mode network. These findings may help us to understand the potential pathophysiological changes in the central nervous system after SCI. (C) 2015 Elsevier Inc. All rights reserved.
Peer Review Status:Awaiting Review
Subjects: Biology >> Biophysics >> Neurosciences submitted time 2016-05-11
Zou, Qihong
Gao, Jia-Hong
Miao, Xinyuan
Liu, Dapeng
Zhuo, Yan
Wang, Danny J. J.
Gao, Jia-Hong
Gao, Jia-Hong
Abstract： Blood oxygenation level dependent (BOLD) and arterial spin labeling (ASL) are two predominant resting-state fMRI techniques in mapping spontaneous brain activities. At single voxel level, cerebral blood flow (CBF) measured by ASL and amplitude of low frequency fluctuations (ALFF) of BOLD have been recognized as useful indices to characterize brain function in health and disease. However, no study has directly compared the test-retest reliability between BOLD and CBF contrasts on the same group of subjects at single voxel level. Moreover, both eyes-open and eyes-closed conditions have been employed as resting states, but it is still not clear which state is more reliable. Here we collected BOLD and ASL data during eyes-open and eyes-closed states across three scanning visits on twenty-two healthy young subjects. CBF-mean, BOLD-and CBF-ALFF were computed to characterize corresponding brain activities at single voxel level. Seed-based functional connectivity (FC) with the posterior cingulate cortex (PCC) was further calculated for both BOLD and CBF data. Intra-class correlation was used as the index of long-term reliability between visits 1 and 2 (two months apart) and short-term reliability between visits 2 and 3 (on the same day). Both short-and long-term reliabilities for CBF-mean and BOLD-ALFF were high, but were lower for CBF-ALFF, BOLD-and CBF-FC in both eyes-open and eyes-closed states. Direct comparisons showed that brain regions with the highest reliability of CBF-mean were mainly in the gray matter. The reliability of CBF-ALFF and BOLD-FC was lower than that of BOLD-ALFF, and the reliability of CBF-FC was lower than those of both CBF-ALFF and BOLD-FC. Furthermore, we observed that reliabilities of the eyes-open state were higher than those of the eyes-closed state for both imaging contrasts, though the effect size was small. Voxel-wise comparisons demonstrated that the long-term reliability of BOLD-ALFF was significantly higher with eyes open in the visual system, and both the short-and long-term reliability of BOLD-FC was slightly higher with eyes open in the default mode network. Moreover, we showed that denoising decreased the reliability of both ALFF and FC of both BOLD and ASL contrasts. In conclusion, our results indicated that CBF-mean and BOLD-ALFF could both be used as reliable indices for characterizing resting-state brain activities at single voxel level and recommended the eyes-open state for resting-state studies, especially for those targeting the visual system and default mode network. (C) 2015 Elsevier Inc. All rights reserved.
Peer Review Status:Awaiting Review
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