scholarly journals Structural and Functional Deficits in Patients with Poststroke Dementia: A Multimodal MRI Study

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Huaying Cai ◽  
Zhiyong Zhao ◽  
Linhui Ni ◽  
Guocan Han ◽  
Xingyue Hu ◽  
...  
Keyword(s):  
Roc Curve ◽  
Brain Activity ◽  
Inferior Frontal Gyrus ◽  
Gray Matter Volume ◽  
Low Frequency ◽  
Superior Temporal Gyrus ◽  
Imaging Data ◽  
Roc Curve Analysis ◽  
Poststroke Dementia ◽  
The Right

Although many neuroimaging studies have reported structural and functional abnormalities in the brains of patients with cognitive impairments following stroke, little is known about the pattern of such brain reorganization in poststroke dementia (PSD). The present study was aimed at investigating alterations in spontaneous brain activity and gray matter volume (GMV) in PSD patients. We collected T1-weighted and resting-state functional magnetic resonance imaging data from 20 PSD patients, 24 poststroke nondementia (PSND) patients, and 21 well-matched normal controls (NCs). We compared the differences among the groups in GMV and the fractional amplitude of low-frequency fluctuations (fALFF). Then, we evaluated the relationship between these brain measures and cognitive assessments and explored the possible distinguisher for PSD by receiver operating characteristic (ROC) curve analysis. PSD patients showed smaller GMV in the right superior temporal gyrus and lower fALFF values in the right inferior frontal gyrus than both PSND patients and NCs, but such differences were not observed between PSND patients and NCs. Moreover, GMV in the left medial prefrontal cortex showed a significant positive correlation with the Mini-Cog assessment in PSD patients, and GMV in the left CPL displayed the highest area under the ROC curve among all the features for classifying PSD versus PSND patients. Our findings suggest that PSD patients show dementia-specific structural and functional alteration patterns, which may help elucidate the pathophysiological mechanisms underlying PSD.

scholarly journals Effect of Repetitive Transcranial Magnetic Stimulation on the Right Superior Temporal Gyrus for Severe Aphasia Caused by Damage to the Left Inferior Frontal Gyrus

2019 ◽  
Vol 11 (2) ◽  
pp. 189-198 ◽  
Author(s):  
Mimpei Kawamura ◽  
Nobuhiro Takahashi ◽  
Yasutaka Kobayashi
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Magnetic Stimulation ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Inferior Frontal Gyrus ◽  
Low Frequency ◽  
Superior Temporal Gyrus ◽  
Verbal Expression ◽  
Left Inferior Frontal Gyrus ◽  
The Right ◽  
Low Frequency Rtms

Several reports on repetitive transcranial magnetic stimulation (rTMS) for the treatment of aphasia caused by damage to the left inferior frontal gyrus state that low-frequency rTMS therapy for the right inferior frontal gyrus, which is contralateral to the focus area, is effective for improving verbal expression. However, most of these reports have studied the effects of rTMS therapy for comparatively mild aphasia. This study attempted to perform low-frequency rTMS on the right posterior superior temporal gyrus (BA22), which is the center for language reception for aphasia patients with a drastic decline in verbal expression due to damage to the left inferior frontal gyrus and a considerable decline in language perception. The participants performed a language task that was displayed on a computer monitor during rTMS. In addition, intensive speech-language and hearing therapy was performed by the therapist after rTMS. This study reports that a resultant improvement in language perception was observed in the activated brain regions based on neuropsychological tests and functional magnetic resonance imaging. This study is considered to be significant as it highlights a new method of rTMS treatment for severe aphasia.

scholarly journals Altered patterns of fractional amplitude of low-frequency fluctuation and regional homogeneity in abstinent methamphetamine-dependent users

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
An Xie ◽  
Qiuxia Wu ◽  
Winson Fu Zun Yang ◽  
Chang Qi ◽  
Yanhui Liao ◽  
...  
Keyword(s):  
Resting State ◽  
Brain Activity ◽  
Inferior Frontal Gyrus ◽  
Low Frequency ◽  
Regional Homogeneity ◽  
Anterior Cingulate ◽  
Frequency Fluctuation ◽  
Early Recovery ◽  
Left Inferior Frontal Gyrus ◽  
The Right

AbstractMethamphetamine (MA) could induce functional and structural brain alterations in dependent subjects. However, few studies have investigated resting-state activity in methamphetamine-dependent subjects (MADs). We aimed to investigate alterations of brain activity during resting-state in MADs using fractional amplitude of low-frequency fluctuation (fALFF) and regional homogeneity (ReHo). We analyzed fALFF and ReHo between MADs (n = 70) and healthy controls (HCs) (n = 84) and performed regression analysis using MA use variables. Compared to HCs, abstinent MADs showed increased fALFF and ReHo values in the bilateral striatum, decreased fALFF in the left inferior frontal gyrus, and decreased ReHo in the bilateral anterior cingulate cortex, sensorimotor cortex, and left precuneus. We also observed the fALFF values of bilateral striatum were positively correlated with the age of first MA use, and negatively correlated with the duration of MA use. The fALFF value of right striatum was also positively correlated with the duration of abstinence. The alterations of spontaneous cerebral activity in abstinent MADs may help us probe into the neurological pathophysiology underlying MA-related dysfunction and recovery. Since MADs with higher fALFF in the right striatum had shorter MA use and longer abstinence, the increased fALFF in the right striatum might implicate early recovery during abstinence.

scholarly journals Common and distinct patterns of intrinsic brain activity alterations in major depression and bipolar disorder: voxel-based meta-analysis

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jiaying Gong ◽  
Junjing Wang ◽  
Shaojuan Qiu ◽  
Pan Chen ◽  
Zhenye Luo ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Major Depression ◽  
Brain Activity ◽  
Meta Analysis ◽  
Inferior Frontal Gyrus ◽  
Superior Temporal Gyrus ◽  
Occipital Cortex ◽  
Anterior Cingulate ◽  
The Right ◽  
Intrinsic Brain Activity

Abstract Identification of intrinsic brain activity differences and similarities between major depression (MDD) and bipolar disorder (BD) is necessary. However, results have not yet yielded consistent conclusions. A meta-analysis of whole-brain resting-state functional MRI (rs-fMRI) studies that explored differences in the amplitude of low-frequency fluctuation (ALFF) between patients (including MDD and BD) and healthy controls (HCs) was conducted using seed-based d mapping software. Systematic literature search identified 50 studies comparing 1399 MDD patients and 1332 HCs, and 15 studies comparing 494 BD patients and 593 HCs. MDD patients displayed increased ALFF in the right superior frontal gyrus (SFG) (including the medial orbitofrontal cortex, medial prefrontal cortex [mPFC], anterior cingulate cortex [ACC]), bilateral insula extending into the striatum and left supramarginal gyrus and decreased ALFF in the bilateral cerebellum, bilateral precuneus, and left occipital cortex compared with HCs. BD showed increased ALFF in the bilateral inferior frontal gyrus, bilateral insula extending into the striatum, right SFG, and right superior temporal gyrus (STG) and decreased ALFF in the bilateral precuneus, left cerebellum (extending to the occipital cortex), left ACC, and left STG. In addition, MDD displayed increased ALFF in the left lingual gyrus, left ACC, bilateral precuneus/posterior cingulate gyrus, and left STG and decreased ALFF in the right insula, right mPFC, right fusiform gyrus, and bilateral striatum relative to BD patients. Conjunction analysis showed increased ALFF in the bilateral insula, mPFC, and decreased ALFF in the left cerebellum in both disorders. Our comprehensive meta-analysis suggests that MDD and BD show a common pattern of aberrant regional intrinsic brain activity which predominantly includes the insula, mPFC, and cerebellum, while the limbic system and occipital cortex may be associated with spatially distinct patterns of brain function, which provide useful insights for understanding the underlying pathophysiology of brain dysfunction in affective disorders, and developing more targeted and efficacious treatment and intervention strategies.

scholarly journals The Functional and Structural Changes of the Brain in Parkinson's Disease Patients with Mild Cognitive Impairment

2020 ◽  
Author(s):  
ji bingjun ◽  
Bingjun Ji ◽  
Ting Zhao ◽  
Xuan Cui ◽  
Jingtao Chen ◽  
...  
Keyword(s):  
Cognitive Impairment ◽  
Patient Group ◽  
Gray Matter ◽  
Inferior Frontal Gyrus ◽  
Superior Temporal Gyrus ◽  
Matter Density ◽  
Imaging Data ◽  
Gray Matter Density ◽  
The Right ◽  
Left Middle

Abstract Background: Parkinson's disease (PD) is often associated with cognitive impairment. However, the neural mechanism of cognitive impairment is not clear. The present study investigated the functional and anatomic changes in PD patients with mild cognitive impairment (MCI) and their correlations with cognitive functions by the application of combined functional and structural analysis. Methods: T1-weighted magnetic resonance imaging (MRI) and resting-state functional MRI data were acquired from 23 PD patients with MCI (PD-MCI), 23 PD patients with normal cognitive function (PD-NCI), and 23 matched healthy controls (HC). The structural imaging data was analyzed by voxel-based morphometry (VBM) and surfaced-based morphometry (SBM) methods to assess the changes of gray matter density and cortical thickness, respectively. And the amplitude of low-frequency fluctuations (ALFF) analysis using resting-state functional imaging data to measure the spontaneous changes of brain activity. Their Correlations with neuropsychological assessments (e.g., Montreal cognitive assessment, MOCA; Mini-mental state examination, MMSE) were also examined. Results: Compared to the HC group, the PD-MCI patient group showed both decreased ALFF in the occipital regions (i.e., left middle occipital gyrus) and parietal regions (i.e., left precuneus) and increased ALFF in the right inferior frontal gyrus and bilateral hippocampus. Also, the PD-MCI patient group showed reduced gray matter density in the right inferior frontal gyrus and middle frontal gyrus. Cortical thinning in the left middle temporal gyrus and right superior temporal gyrus was found in the PD_MCI patient group relative to the control group. Furthermore, ALFF of the right hippocampus and gray matter density of right frontal gyrus was correlated with cognitive impairment (e.g., MOCA ), respectively. Cortical thickness of right superior temporal gyrus was also associated with cognitive deficit (e.g., MMSE ). Conclusion: MCI in PD is associated with widespread brain functional and structural alternations. The combination of functional and structural abnormalities may be related to subtle cognitive impairment in PD.

scholarly journals Gray matter volume alterations in patients with strabismus and amblyopia: voxel-based morphometry study

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Ting Su ◽  
Pei-Wen Zhu ◽  
Biao Li ◽  
Wen-Qing Shi ◽  
Qi Lin ◽  
...  
Keyword(s):  
Gray Matter ◽  
Gray Matter Volume ◽  
Superior Temporal Gyrus ◽  
Curve Analysis ◽  
Parahippocampal Gyrus ◽  
Voxel Based Morphometry ◽  
Roc Curve Analysis ◽  
Matter Volume ◽  
The Mean ◽  
The Right

AbstractThis study proposes the use of the voxel-based morphometry (VBM) technique to investigate structural alterations of the cerebral cortex in patients with strabismus and amblyopia (SA). Sixteen patients with SA and sixteen healthy controls (HCs) underwent magnetic resonance imaging. Original whole brain images were analyzed using the VBM method. Pearson correlation analysis was performed to evaluate the relationship between mean gray matter volume (GMV) and clinical manifestations. Receiver operating characteristic (ROC) curve analysis was applied to classify the mean GMV values of the SA group and HCs. Compared with the HCs, GMV values in the SA group showed a significant difference in the right superior temporal gyrus, posterior and anterior lobes of the cerebellum, bilateral parahippocampal gyrus, and left anterior cingulate cortex. The mean GMV value in the right superior temporal gyrus, posterior and anterior lobes of the cerebellum, and bilateral parahippocampal gyrus were negatively correlated with the angle of strabismus. The ROC curve analysis of each cerebral region confirmed the accuracy of the area under the curve. Patients with SA have reduced GMV values in some brain regions. These findings might help to reveal the potential pathogenesis of SA and its relationship with the atrophy of specific regions of the brain.

scholarly journals Altered Spontaneous Brain Activity in Cortical and Subcortical Regions in Parkinson’s Disease

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Jie Xiang ◽  
Xiuqin Jia ◽  
Huizhuo Li ◽  
Jiawei Qin ◽  
Peipeng Liang ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Prefrontal Cortex ◽  
Brain Activity ◽  
Gray Matter Volume ◽  
Low Frequency ◽  
Head Motion ◽  
Gender Education ◽  
Subcortical Regions ◽  
The Right

Purpose. The present study aimed to explore the changes of amplitude of low-frequency fluctuations (ALFF) at rest in patients with Parkinson’s disease (PD).Methods. Twenty-four PD patients and 22 healthy age-matched controls participated in the study. ALFF was measured on the whole brain of all participants. A two-samplet-test was then performed to detect the group differences with age, gender, education level, head motion, and gray matter volume as covariates.Results. It was showed that PD patients had significantly decreased ALFF in the left thalamus/caudate and right insula/inferior prefrontal gyrus, whereas they had increased ALFF in the right medial prefrontal cortex (BA 8/6) and dorsolateral prefrontal cortex (BA 9/10).Conclusions. Our results indicated that significant alterations of ALFF in the subcortical regions and prefrontal cortex have been detected in PD patients, independent of age, gender, education, head motion, and structural atrophy. The current findings further provide insights into the biological mechanism of the disease.

Timing, Storage, and Comparison of Stimulus Duration Engage Discrete Anatomical Components of a Perceptual Timing Network

2008 ◽  
Vol 20 (12) ◽  
pp. 2185-2197 ◽  
Author(s):  
Jennifer T. Coull ◽  
Bruno Nazarian ◽  
Franck Vidal
Keyword(s):  
Stimulus Duration ◽  
Brain Activity ◽  
Temporal Discrimination ◽  
Superior Temporal Gyrus ◽  
Motor Preparation ◽  
Long Term Memory ◽  
Temporal Encoding ◽  
Perceptual Timing ◽  
The Right

The temporal discrimination paradigm requires subjects to compare the duration of a probe stimulus to that of a sample previously stored in working or long-term memory, thus providing an index of timing that is independent of a motor response. However, the estimation process itself comprises several component cognitive processes, including timing, storage, retrieval, and comparison of durations. Previous imaging studies have attempted to disentangle these components by simply measuring brain activity during early versus late scanning epochs. We aim to improve the temporal resolution and precision of this approach by using rapid event-related functional magnetic resonance imaging to time-lock the hemodynamic response to presentation of the sample and probe stimuli themselves. Compared to a control (color-estimation) task, which was matched in terms of difficulty, sustained attention, and motor preparation requirements, we found selective activation of the left putamen for the storage (“encoding”) of stimulus duration into working memory (WM). Moreover, increased putamen activity was linked to enhanced timing performance, suggesting that the level of putamen activity may modulate the depth of temporal encoding. Retrieval and comparison of stimulus duration in WM selectively activated the right superior temporal gyrus. Finally, the supplementary motor area was equally active during both sample and probe stages of the task, suggesting a fundamental role in timing the duration of a stimulus that is currently unfolding in time.

Humor Comprehension and Appreciation: An fMRI Study

2006 ◽  
Vol 18 (11) ◽  
pp. 1789-1798 ◽  
Author(s):  
Angela Bartolo ◽  
Francesca Benuzzi ◽  
Luca Nocetti ◽  
Patrizia Baraldi ◽  
Paolo Nichelli
Keyword(s):  
Left Hemisphere ◽  
Language Processing ◽  
Inferior Frontal Gyrus ◽  
Brain Lesion ◽  
Superior Temporal Gyrus ◽  
Middle Temporal Gyrus ◽  
Stage Model ◽  
Human Beings ◽  
Two Stage ◽  
The Right

Humor is a unique ability in human beings. Suls [A two-stage model for the appreciation of jokes and cartoons. In P. E. Goldstein & J. H. McGhee (Eds.), The psychology of humour. Theoretical perspectives and empirical issues. New York: Academic Press, 1972, pp. 81–100] proposed a two-stage model of humor: detection and resolution of incongruity. Incongruity is generated when a prediction is not confirmed in the final part of a story. To comprehend humor, it is necessary to revisit the story, transforming an incongruous situation into a funny, congruous one. Patient and neuroimaging studies carried out until now lead to different outcomes. In particular, patient studies found that right brain-lesion patients have difficulties in humor comprehension, whereas neuroimaging studies suggested a major involvement of the left hemisphere in both humor detection and comprehension. To prevent activation of the left hemisphere due to language processing, we devised a nonverbal task comprising cartoon pairs. Our findings demonstrate activation of both the left and the right hemispheres when comparing funny versus nonfunny cartoons. In particular, we found activation of the right inferior frontal gyrus (BA 47), the left superior temporal gyrus (BA 38), the left middle temporal gyrus (BA 21), and the left cerebellum. These areas were also activated in a nonverbal task exploring attribution of intention [Brunet, E., Sarfati, Y., Hardy-Bayle, M. C., & Decety, J. A PET investigation of the attribution of intentions with a nonverbal task. Neuroimage, 11, 157–166, 2000]. We hypothesize that the resolution of incongruity might occur through a process of intention attribution. We also asked subjects to rate the funniness of each cartoon pair. A parametric analysis showed that the left amygdala was activated in relation to subjective amusement. We hypothesize that the amygdala plays a key role in giving humor an emotional dimension.

scholarly journals Prefrontal High Gamma in ECoG tags periodicity of musical rhythms in perception and imagination

2019 ◽  
Author(s):  
S. A. Herff ◽  
C. Herff ◽  
A. J. Milne ◽  
G. D. Johnson ◽  
J. J. Shih ◽  
...  
Keyword(s):  
Auditory Processing ◽  
Right Hemisphere ◽  
Brain Activity ◽  
Activity Patterns ◽  
Superior Temporal Gyrus ◽  
Gamma Activity ◽  
Rhythm Perception ◽  
High Gamma ◽  
The Right ◽  
Musical Rhythms

AbstractRhythmic auditory stimuli are known to elicit matching activity patterns in neural populations. Furthermore, recent research has established the particular importance of high-gamma brain activity in auditory processing by showing its involvement in auditory phrase segmentation and envelope-tracking. Here, we use electrocorticographic (ECoG) recordings from eight human listeners, to see whether periodicities in high-gamma activity track the periodicities in the envelope of musical rhythms during rhythm perception and imagination. Rhythm imagination was elicited by instructing participants to imagine the rhythm to continue during pauses of several repetitions. To identify electrodes whose periodicities in high-gamma activity track the periodicities in the musical rhythms, we compute the correlation between the autocorrelations (ACC) of both the musical rhythms and the neural signals. A condition in which participants listened to white noise was used to establish a baseline. High-gamma autocorrelations in auditory areas in the superior temporal gyrus and in frontal areas on both hemispheres significantly matched the autocorrelation of the musical rhythms. Overall, numerous significant electrodes are observed on the right hemisphere. Of particular interest is a large cluster of electrodes in the right prefrontal cortex that is active during both rhythm perception and imagination. This indicates conscious processing of the rhythms’ structure as opposed to mere auditory phenomena. The ACC approach clearly highlights that high-gamma activity measured from cortical electrodes tracks both attended and imagined rhythms.

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.

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