Study on brain mechanism of rehabilitation training of articulation disorder in cleft lip and palate patients based on functional magnetic resonance imaging / 生物医学工程学杂志

The cleft lip and palate (CLP) is one of the most common craniofacial malformations in humans. We collected functional magnetic resonance data of 23 CLP patients before rehabilitation training (Bclp) and 23 CLP patients after rehabilitation training (Aclp), who were performing Chinese character pronunciation tasks, and performed brain activation analysis to explore the changes of brain mechanism in CLP patients after articulation disorder rehabilitation training. The study found that Aclp group had significant activation in the motor cortex, Broca area, Wernicke area and cerebellum. While the Bclp group had weak activation in the motor cortex with a small activation range. By comparing the differences and co-activated brain regions between the two groups, we found that rehabilitation training increased the activity level of negatively activated brain areas (cerebellum, left motor area, Wernicke area, etc.) to a positive level. At the same time, the activity level of weakly activated brain areas (right motor area, Broca area, etc.) was also increased. Rehabilitation training promoted the activity level of articulation-related brain regions. So that the activation intensity of articulation-related brain regions can be used as a quantifiable objective evaluation index to evaluate the effect of rehabilitation training, which is of great significance for the formulation of rehabilitation training programs.

The characteristics of cortical activation when hemiplegic stroke survivors walk assisted by functional electrical stimulation / 中华物理医学与康复杂志

Objective:To explore the characteristics of cortical activation during the stimulation-assisted walking of hemiplegic stroke survivors using functional near-infrared spectroscopy (fNIRS).Methods:Eight stroke survivors with right hemiplegia (average age 44.4±7.2 years) in a self-controlled study each walked at 2km/h on a treadmill, alone and assisted by functional electronic stimulation (FES). Real-time near-infrared spectroscopic images were recorded. The Matlab NIRS-SPM toolkit was employed to calculate the changes in oxyhemoglobin concentration in different cortical regions. A general linear model was evaluated which integrated the task effects, and version 20.0 of the SPSS statistical software was used to perform single sample or paired sample t-tests of the beta values so as to produce activation hot maps of the significant differences.Results:During unassisted walking channels 8, 10, 11, 13-20, 23-28, 30 and 32-37 were significantly activated. During FES-assisted walking it was the same channels plus channels 9 and 22, 31. The results suggest that in walking the cortical regions activated are mainly located in M1 of the unaffected hemisphere, supplemented by M1 and SMA, PMC and S1 in the affected hemisphere. There were significant differences in the activation of channels 9, 24, 27, 32, 33 between the two walking tasks. FES-assistance enhances S1 activation on the unaffected side, as well as the SMA and PMC of the affected side more significantly.Conclusions:Bilateral asymmetrical activation is found mostly in M1 during walking with or without FES assistance. FES assistance significantly strengthens the compensatory activation of the PMC and SMA of the affected hemisphere while walking for those with hemiplegia.

An fMRI study on the specific modulation of brain responses to transient pain by anxiety in college students / 中华行为医学与脑科学杂志

Objective:To investigate whether anxiety state and anxiety trait modulate specifically pain-induced brain responses by comparing the brain activations induced by painful stimulation and those by tactile stimulation in college students with different levels of anxiety state or anxiety trait.Methods:From April 2017 to September 2017, sixty-two college students were tested in Tianjin Medical University General Hospital.Each subject’s anxiety trait and anxiety state were assessed by the state-trait anxiety inventory (STAI) prior to the fMRI experiment.During the fMRI experiment, each subject received painful and tactile stimuli.Their brain responses to each stimulus were collected by the MRI scanner, and the perceived intensity rating of each stimulus was collected using the visual analogue scale (VAS). The pain and tactile brain activation values of subjects with different state anxiety levels and different trait anxiety levels were compared.The fMRI brain activation was detected using general linear model.For each type of anxiety (state or trait), two-way ANOVA was performed to detect the interaction between anxiety level and stimulus modality on brain responses and two-sample t-tests were performed to analyze the specific form of interaction in each brain region. Results:There were interactions between state anxiety and stimulation modality on the activation intensity of bilateral posterior parietal lobe, dorsolateral prefrontal lobe and other brain regions( P<0.05, cluster-level FWE corrected) .The brain responses to tactile stimuli (5.66±0.65) in these areas were significantly stronger than those to painful stimuli (1.24±0.55) in the group of middle-level anxiety state ( P<0.001), but no significant difference was found in the other two groups (both P>0.05). For anxiety trait, a few brain areas in bilateral occipital cortex showed significant interactions between anxiety level and stimulus modality.The brain responses to tactile stimuli (8.38±1.00) in these areas were significantly stronger than those to painful stimuli (3.19±1.12) in the group of high-level anxiety trait ( P=0.001), but no significant difference was found in the other two groups (both P>0.05). Conclusion:The modulatory effects of anxiety (both state and trait) on brain responses are different between painful and tactile conditions.It provides important evidence for unveiling the brain mechanisms of the specific modulation of anxiety on pain, and suggests that patients' anxiety trait and anxiety state should be considered during clinical treatment of pain.

The validity of different multiple comparison correction methods in the analysis of brain function image data / 中华行为医学与脑科学杂志

Objective@#To explore the effectiveness of different multiple comparisons correction methods by comparing the detection rate and false positive rate of brain activation analysis using functional magnetic resonance imaging (fMRI) data.@*Methods@#On the basis of task-based fMRI dataset (including low-intensity and high-intensity stimuli condition, n=20) and resting-state fMRI dataset(n=32), brain activation results were corrected by multiple comparsion correction methods in SPM and SnPM13 software, and the activation detection rate and false positive rate were compared with different correction methods.@*Results@#Voxel-or peak-based correction methods had relatively low false positive rate.When P<0.05 after correction, the proportion of the subjects with false-positive were 0.19 and 0.16, and the number of false-positive voxels were 404 and 2 448, respectively.But the two methods had low detection rate, which were more suitable for detecting strong activation.While cluster-based correction methods had relative high detection rate and high false positive rate.When P<0.05 after correction, the proportion of the subjects with false-positive were 0.34 and 0.38, and the number of false-positive voxels were 7 870 and 8 320, respectively.And thus they were more suitable for detecting weak activation. Group-level analysis could effectively reduce false positive rate.@*Conclusion@#In practice, researchers should choose a suitable correction method based on their specific research objectives and data to achieve a balance between the detection rate and false positive rate.

The validity of different multiple comparison correction methods in the analysis of brain function im-age data / 中华行为医学与脑科学杂志

Objective To explore the effectiveness of different multiple comparisons correction methods by comparing the detection rate and false positive rate of brain activation analysis using functional magnetic resonance imaging ( fMRI) data. Methods On the basis of task-based fMRI dataset ( including low-intensity and high-intensity stimuli condition,n=20) and resting-state fMRI dataset( n=32),brain acti-vation results were corrected by multiple comparsion correction methods in SPM and SnPM13 software,and the activation detection rate and false positive rate were compared with different correction methods. Results Voxel-or peak-based correction methods had relatively low false positive rate. When P<0. 05 after correction,the proportion of the subjects with false-positive were 0. 19 and 0. 16,and the number of false-pos-itive voxels were 404 and 2 448,respectively. But the two methods had low detection rate,which were more suitable for detecting strong activation. While cluster-based correction methods had relative high detection rate and high false positive rate. When P<0. 05 after correction,the proportion of the subjects with false-posi-tive were 0. 34 and 0. 38,and the number of false-positive voxels were 7 870 and 8 320,respectively. And thus they were more suitable for detecting weak activation. Group-level analysis could effectively reduce false positive rate. Conclusion In practice,researchers should choose a suitable correction method based on their specific research objectives and data to achieve a balance between the detection rate and false positive rate.

Activation of the Brain to Postpone Dementia: A Concept Originating from Postmortem Human Brain Studies / 神经科学通报·英文版

Alzheimer's disease (AD) is characterized by decreased neuronal activity and atrophy, while hyperactivity of neurons seems to make them resistant to aging and neurodegeneration, a phenomenon which we have paraphrased as 'use it or lose it'. Our hypothesis proposes that (1) during their functioning, neurons are damaged; (2) accumulation of damage that is not repaired is the basis of aging; (3) the vulnerability to AD is determined by the genetic background and the balance between the amount of damage and the efficiency of repair, and (4) by stimulating the brain, repair mechanisms are stimulated and cognitive reserve is increased, resulting in a decreased rate of aging and risk for AD. Environmental stimulating factors such as bilingualism/multilingualism, education, occupation, musical experience, physical exercise, and leisure activities have been reported to reduce the risk of dementia and decrease the rate of cognitive decline, although methodological problems are present.

Functional MRI Characteristics in Visual Cortex (BA 17, 18 and 19) Corresponding to the Visual Field of Normal, Glaucoma Suspect (GS) and Primary Open Angle Glaucoma (POAG) Patients / Jurnal Sains Kesihatan Malaysia

The purpose of this study was to characterize, differentiate and correlate visual field and brain activation in visual cortex for normal, glaucoma suspect (GS) and primary open angle glaucoma (POAG) participants using Standard Automated Perimetry (SAP) and functional Magnetic Resonance Imaging (fMRI) respectively. The fMRI scans and SAP test were both carried out in Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM). Two types of black-and-white checkerboard pattern were displayed to the participants during the fMRI scans. The fMRI data were analyzed using WFU pickatlas toolbox targeting visual cortex area. The results showed that there was no significant difference in number of activated voxel between the three groups in visual cortex (BA 17, 18 and 19) while viewing all the given stimuli (p > 0.05). The pattern standard deviation (PSD) of SAP for visual field also revealed no significant differences (p > 0.05) in all groups of participants. However, negative correlation between PSD and fMRI activation was observed. The PSD values increased with a decrease in fMRI activation. With reference to visual field analysis, the results suggest that glaucomatous neuropathy of POAG patients has led to a gradual decrease in visual cortex activation and a gradual increase in PSD.

Blood oxygen level and the pathogenic mechanism of expressive aphasia after stroke / 中华物理医学与康复杂志

Objective To evaluate the activation patterns in the cortexes of expressive aphasics after stroke so as to explore the pathogenic mechanism of expressive aphasia.Methods Blood oxygen level dependent functional magnetic resonance imaging (BOLD-fMRI) was the method of choice.It was administered to 9 subjects with expressive aphasia at 1 to 3 months post-stroke onset and to 10 healthy controls.Active areas in the patients' brains were observed using a block-designed picture-naming task,and language function was tested with the China Rehabilitation Research Center's aphasia examination (CRRCAE).The control group received BOLD-fMRI only.SPM8 software was used to process the fMRI data.Results Differences were observed in the mapping of activated areas between the two groups,but many activated areas showed no difference.Significant differences in activation were observed in areas associated with vision,language and cognition,including the bilateral inferior frontal gyrus,the bilateral superior temporal gyrus,the bilateral insula,the bilateral basal ganglia,the left superior frontal gyrus,the left middle frontal gyrus,the left precentral gyrus,the left thalamus,and the left middle temporal gyrus.All the patients had activated cortex regions associated with visual processing in the left and/or right hemisphere,such as the middle frontal gyrus,the middle temporal gyrus,the lingual gyrus and the fusiform gyrus.The activation volumes in the left hemisphere were significantly smaller than those in normal adults.Regions related to language such as the left inferior frontal gyrus (Broca's area),the left middle frontal gyrus,and the right inferior frontal gyrus (the mirror region of Broca's area) were activated in some of them.While the activation frequency,activated volume and activation intensity generally were all less in the patients than in the controls,the activation intensity in the right superior temporal gyrus,the bilateral superior parietal lobule and the left inferior temporal gyrus were stronger.Conclusions Language production may be associated with multiple,interconnected regions.The right hemisphere participates in natural language processing.Aphasia damages both linguistic and cognitive areas,reducing activation in Broca's aphasia.Activation areas in the left hemisphere and the right inferior frontal gyrus decrease significantly,while some regions in the right hemisphere are relatively more activated.The right inferior frontal gyrus may play a different role in language recovery at different periods of aphasia after stroke.

Investigating Brain Activation and Neural Effi cacy During Simple Arithmetic Addition Task in Quiet and in Noise: An fMRI Study / Jurnal Sains Kesihatan Malaysia

Knowledge about the hemodynamic model that mediates synaptic activity and measured magnetic resonance signal is essential in understanding brain activation. Neural effi cacy is a hemodynamic parameter that would change the evoked hemodynamic responses. In this work, brain activation and neural effi cacy of the activated brain areas during simple addition task in two different backgrounds were studied using fMRI. The objectives were to determine the activated areas during the performance of arithmetic addition in quiet (AIQ) and noisy (AIN) background and to investigate the relationship between neural effi cacy and height extent of activation for the respective areas. Eighteen healthy male participants performed simple arithmetic addition in quiet and in noise. Bilateral cerebellum, superior temporal gyrus (STG), temporal pole (TP) and supplementary motor area (SMA) were signifi cantly (p < 0.05) activated during AIQ and AIN. Left middle frontal gyrus (L-MFG), right superior frontal gyrus (R-SFG), right superior orbital gyrus (R-SOG) and bilateral insula were more active in quiet as compared to in noise while the left middle cingulate cortex (L-MCC), left amygdala (L-AMG), right temporal pole (R-TP) and left cerebellum (L-CER) were more active in noise as compared to in quiet. The t value for most of the activated regions was found to be inversely proportional to the neural effi cacy. Signifi cant (p < 0.05) negative relationship between t value and neural effi cacy were found for R-STG and bilateral cerebellum during AIQ, while for AIN, similar relationships were found in R-CER, R-STG and R-TP. This study suggests that while being signifi cantly activated, the hemodynamic responses of these brain regions could have been suppressed by the stimulus resulting in an intensity decrease with increasing neural efficacy

NAA and NAAG variation in neuronal activation during visual stimulation

N-acetyl-aspartyl-glutamate (NAAG) and its hydrolysis product N-acetyl-L-aspartate (NAA) are among the most important brain metabolites. NAA is a marker of neuron integrity and viability, while NAAG modulates glutamate release and may have a role in neuroprotection and synaptic plasticity. Investigating on a quantitative basis the role of these metabolites in brain metabolism in vivo by magnetic resonance spectroscopy (MRS) is a major challenge since the main signals of NAA and NAAG largely overlap. This is a preliminary study in which we evaluated NAA and NAAG changes during a visual stimulation experiment using functional MRS. The paradigm used consisted of a rest period (5 min and 20 s), followed by a stimulation period (10 min and 40 s) and another rest period (10 min and 40 s). MRS from 17 healthy subjects were acquired at 3T with TR/TE = 2000/288 ms. Spectra were averaged over subjects and quantified with LCModel. The main outcomes were that NAA concentration decreased by about 20% with the stimulus, while the concentration of NAAG concomitantly increased by about 200%. Such variations fall into models for the energy metabolism underlying neuronal activation that point to NAAG as being responsible for the hyperemic vascular response that causes the BOLD signal. They also agree with the fact that NAAG and NAA are present in the brain at a ratio of about 1:10, and with the fact that the only known metabolic pathway for NAAG synthesis is from NAA and glutamate.

Brain Activation in Response to Visually Evoked Sexual Arousal in Male-to-Female Transsexuals: 3.0 Tesla Functional Magnetic Resonance Imaging

OBJECTIVE: This study used functional magnetic resonance imaging (fMRI) to contrast the differential brain activation patterns in response to visual stimulation with both male and female erotic nude pictures in male-to-female (MTF) transsexuals who underwent a sex reassignment surgery. MATERIALS AND METHODS: A total of nine healthy MTF transsexuals after a sex reassignment surgery underwent fMRI on a 3.0 Tesla MR Scanner. The brain activation patterns were induced by visual stimulation with both male and female erotic nude pictures. RESULTS: The sex hormone levels of the postoperative MTF transsexuals were in the normal range of healthy heterosexual females. The brain areas, which were activated by viewing male nude pictures when compared with viewing female nude pictures, included predominantly the cerebellum, hippocampus, putamen, anterior cingulate gyrus, head of caudate nucleus, amygdala, midbrain, thalamus, insula, and body of caudate nucleus. On the other hand, brain activation induced by viewing female nude pictures was predominantly observed in the hypothalamus and the septal area. CONCLUSION: Our findings suggest that distinct brain activation patterns associated with visual sexual arousal in postoperative MTF transsexuals reflect their sexual orientation to males.

Neuro-Anatomical Evaluation of Human Suitability for Rural and Urban Environment by Using fMRI / 의학물리

The purpose of this study was to identify different cerebral areas of the human brain associated with rural and urban picture stimulation using a 3.0 Tesla functional magnetic resonance imaging (fMRI) and further to investigate the human suitability for rural and urban environments. A total of 27 right-handed participants (mean age: 27.3+/-3.7) underwent fMRI study on a 3.0T MR scanner. The brain activation patterns were induced by visual stimulation with each rural and urban sceneries. The participants were divided into two groups as 26 subjects favorable to rural scenery and 14 subjects unfavorable to urban scenery based on their filled-in questionnaire. The differences of the brain activation in response to two extreme types of pictures by the two sample t-test were characterized as follows: the activation areas observed in rural scenery over urban were the insula, middle frontal gyrus, precuneus, caudate nucleus, superior parietal gyrus, superior occipital gyrus, fusiform gyrus, and globus pallidus. In urban scenery over rural, the inferior frontal gyrus, parahippocampal gyrus, postcentral gyrus, superior temporal gyrus, amygdala, and posterior cingulate gyrus were activated. The fMRI patterns also clearly show that rural scenery elevated positive emotion such as happiness and comfort. On the contrary, urban scenery elevated negative emotion, resulting in activation of the amygdala which is the key region for the feelings of fear, anxiety and unpleasantness. This study evaluated differential cerebral areas of the human brain associated with rural and urban picture stimulation using a 3.0 Tesla fMRI. These findings will be useful as an objective evaluation guide to human suitability for ecological environments that are related to brain activation with joy, anger, sorrow and pleasure.

Functional Neuroanatomy Associated with Natural and Urban Scenic Views in the Human Brain: 3.0T Functional MR Imaging

OBJECTIVE: By using a functional magnetic resonance imaging (fMRI) technique we assessed brain activation patterns while subjects were viewing the living environments representing natural and urban scenery. MATERIALS AND METHODS: A total of 28 healthy right-handed subjects underwent an fMRI on a 3.0 Tesla MRI scanner. The stimulation paradigm consisted of three times the rest condition and two times the activation condition, each of which lasted for 30 and 120 seconds, respectively. During the activation period, each subject viewed natural and urban scenery, respectively. RESULTS: The predominant brain activation areas observed following exposure to natural scenic views in contrast with urban views included the superior and middle frontal gyri, superior parietal gyrus, precuneus, basal ganglia, superior occipital gyrus, anterior cingulate gyrus, superior temporal gyrus, and insula. On the other hand, the predominant brain activation areas following exposure to urban scenic views in contrast with natural scenes included the middle and inferior occipital gyri, parahippocampal gyrus, hippocampus, amygdala, anterior temporal pole, and inferior frontal gyrus. CONCLUSION: Our findings support the idea that the differential functional neuroanatomies for each scenic view are presumably related with subjects' emotional responses to the natural and urban environment, and thus the differential functional neuroanatomy can be utilized as a neural index for the evaluation of friendliness in ecological housing.

Time-Course Analysis of the Neuroanatomical Correlates of Sexual Arousal Evoked by Erotic Video Stimuli in Healthy Males

OBJECTIVE: To assess the dynamic activations of the key brain areas associated with the time-course of the sexual arousal evoked by visual sexual stimuli in healthy male subjects. MATERIALS AND METHODS: Fourteen right-handed heterosexual male volunteers participated in this study. Alternatively combined rest period and erotic video visual stimulation were used according to the standard block design. In order to illustrate and quantify the spatiotemporal activation patterns of the key brain regions, the activation period was divided into three different stages as the EARLY, MID and LATE stages. RESULTS: For the group result (p < 0.05), when comparing the MID stage with the EARLY stage, a significant increase of the brain activation was observed in the areas that included the inferior frontal gyrus, the supplementary motor area, the hippocampus, the head of the caudate nucleus, the midbrain, the superior occipital gyrus and the fusiform gyrus. At the same time, when comparing the EARLY stage with the MID stage, the putamen, the globus pallidus, the pons, the thalamus, the hypothalamus, the lingual gyrus and the cuneus yielded significantly increased activations. When comparing the LATE stage with the MID stage, all the above mentioned brain regions showed elevated activations except the hippocampus. CONCLUSION: Our results illustrate the spatiotemporal activation patterns of the key brain regions across the three stages of visual sexual arousal.

Characteristics of Brain Activation during Semantic Processing in Schizophrenia / 신경정신의학

OBJECTIVES: Investigators reported that schizophrenies have deficits in semantic processing. However, it is unclear which brain area is associated with semantic processing dysfunction in schizophrenia. This study was designed to explore the activated brain areas associated with semantic processing in schizophrenic patients compared with controls. METHODS: Twelve patients with schizophrenia and twelve healthy controls were studied under two different visual task conditions. Subjects were required to respond to a specific semantic category in a specific figure among word-figure stimuli during the first task, and to respond to a specific figure among figure-only stimuli during the second task. Brain activation during each task was measured using [15O]H2O PET. Activated brain areas were analyzed by subtraction methods using SPM99 in each group. RESULTS: In healthy control group, the left superior temporal gyrus, left premotor area and left cerebellum were activated during semantic processing along with activation of the left inferior temporal gyrus which is a main semantic processing area. But activation of the main semantic processing area in patient group was more posteriorly than controls. In contrast with control group, lateralized activation pattern to the left and cerebellar activation were not observed in patient group. CONCLUSION: Our results suggest that patient's deficit in elaboration due to early semantic processing, decreased efficacy due to the loss of lateralization and decreased modulatory ability due to the loss of cerebellar activation may be involved in the characteristics of brain activation patterns in schizophrenia. This distorted semantic processing in schizophrenia may play a role as one of the basic determinants in thought disorder.

Functional Mapping of the Neural Basis for the Encoding and Retrieval of Human Episodic Memory Using H215O PET / 대한핵의학회잡지

PURPOSE: Episodic memory is described as an 'autobiographical' memory responsible for storing a record of the events in our lives. We performed functional brain activation study using H215O PET to reveal the neural basis of the encoding and the retrieval of episodic memory in human normal volunteers. MATERIALS AND METHODS: Four repeated H215O PET scans with two reference and two activation tasks were performed on 6 normal volunteers to activate brain areas engaged in encoding and retrieval with verbal materials. Images from the same subject were spatially registered and normalized using linear and nonlinear transformation. Using the means and variances for every condition which were adjusted with analysis of covariance, t-statistic analysis were performed voxel-wise. RESULTS: Encoding of episodic memory activated the opercular and triangular parts of left inferior frontal gyrus, right prefrontal cortex, medial frontal area, cingulate gyrus, posterior middle and inferior temporal gyri, and cerebellum, and both primary visual and visual association areas. Retrieval of episodic memory activated the triangular part of left inferior frontal gyrus and inferior temporal gyrus, right prefrontal cortex and medial temporal area, and both cerebellum and primary visual and visual association areas. The activations in the opercular part of left inferior frontal gyrus and the right prefrontal cortex meant the essential role of these areas in the encoding and retrieval of episodic memory. CONCLUSION: We could localize the neural basis of the encoding and retrieval of episodic memory using H215O PET, which was partly consistent with the hypothesis of hemispheric encoding/retrieval asymmetry.

Technical Improvement of Functional MRI for Clinical Application

BACKGROUND: Functional MRI is a new neuroimaging method that detects focal blood flow change associated with neural activation. This study aimed at improving it for use as a clinical test. METHODS: We separated image reconstruction from scan acquisition as an off-line process, systematized post-processing stages, and employed SPM96 package for statistical analysis. Tasks easy enough for most neurological patients were designed for activation of motor, somatosensory, visual, and language areas. From twenty consecutive patients admitted to neurology wards, frequency of expected activation and inactivation among defined regions of interest was obtained as a measure of sensitivity and quasi-specificity. RESULTS: It took about 4 minutes for data acquisition per task condition. Thus within half an hour all four tasks were tested in cooperative patients. Post-processing took about an hour per task condition, using PC-based analysis packages. Sensitivity and quasi-specificity were about 70% and 90%, respectively. CONCLUSIONS: Our newly developed method shortened the time for fMRI acquisition and systematized post-scan analysis. Data obtained from patients showed acceptable reliability for clinical use, but further research and improvement should be necessary.