Showing 31 results for Mri
Hussain Jaber, Hadeel Aljobouri, Orhan Kocak, Oktay Algin, Ilyas Cankaya,
Volume 0, Issue 0 (3-2018)
Abstract
In this work, a novel conversion and visualization fMRI (VCfMRI) toolbox is proposed. The VCfMRI tool is enabled to read, write 3-D volume data (.dcm, .nii, .img, hdr and .mat format) as well as multi conversion operations between them are performed in the same package. In the current work, real fMRI data are used and all data are acquired by MRI scanner type Siemens/3T in National Magnetic Resonance Research Center (UMRAM)-Bilkent University. About 62 analyses functions have been implemented and incorporated in analysis about 7 GUI tools for multiple conversions of fMRI modalities, reading/writing and viewing in all fMRI data formats, visualizing 3-dimensional (sagittal, coronal and horizontal slices) statistical and non-statistical neuroimaging, thresholding and overlaying viewing. The presented package is a simple tool to address several issues that related to complexity in visualizing and conversion between multi-formats of fMRI data. This work enables the user to visualize and deals with fMRI data in an easy way especially for physicians, healthcare specialists and researchers whose faced challenges about how handling with these type of data.
Meghdad Ashtiyani, Parmida Moradi Birgani, Maryam Soleimani, Seyed Behnamedin Jameie, Amin Shahrokhi, Mohammad Reze Deevband, Mohammad Mehdi Mirbagheri,
Volume 0, Issue 0 (3-2018)
Abstract
Introduction: Cerebral Palsy (CP) is one of the most common causes of motor disability in childhood. Since CP is a corollary to brain damage, persistent treatment should accompany an alteration in brain functional activity in line with clinical improvements.
Methods: Fourteen children with spastic hemiplegia CP were randomly divided into 2 groups. The study group (8yrs-5mos) underwent 45min AlterG training sessions 3 times/week for 8 weeks, while the control group (8yrs-2mos) received the same amount of occupational therapy (OT). Functional magnetic resonance imaging (fMRI) was conducted to quantify brain activation during the performance of passive tasks including ankle plantarflexion to dorsiflexion and knee flexion to extension over the range of motion. Walking capacity was assessed using the Timed-Up-and-Go, 10-meter, and 6-minute walk tests. All evaluations were performed before and after training and compared between the two groups.
Results: We were able to detect the signatures of ankle and knee passive movement tasks in the fMRI and characterize them in terms of activated voxels. The pre-post activation changes following the completion of training course showed that the elicited motor cortex activation was greater for the ankle than the knee tasks. For the ankle, primary motor cortex, precentral gyrus and corpus callosum showed significant enhancement in most study participants. The results indicated 16.1% more active voxels in the study than control groups. Similarly, clinical outcome measures improved over twice as much in this group.
Conclusions: AlterG training could be a potentially effective therapeutic intervention for improving gait and balance impairments in children with CP.
Mehdi Behroozi, Mohammad Reza Daliri, Huseyin Boyaci,
Volume 2, Issue 4 (8-2011)
Abstract
Functional magnetic resonance imaging (fMRI) is a safe and non-invasive way to assess brain functions by using signal changes associated with brain activity. The technique has become a ubiquitous tool in basic, clinical and cognitive neuroscience. This method can measure little metabolism changes that occur in active part of the brain. We process the fMRI data to be able to find the parts of brain that are involve in a mechanism, or to determine the changes that occur in brain activities due to a brain lesion. In this study we will have an overview over the methods that are used for the analysis of fMRI data.
Farzaneh Pouladi, Habib Ganjgahi, Ali Zadehmohammadi, Mohammad Ali Oghabian,
Volume 3, Issue 1 (10-2011)
Abstract
Introduction: The aim of this study was to get to a neurological evaluation of one of the Persian music scales, Homayoun, on brain activation of non-musician subjects. We selected this scale because Homayoun is one of the main scales in Persian classical music which is similar to minor mode in western scales.
Methods:
This study was performed on 19 right handed subjects, Aging 22-31. Here some pieces from Homayoun Dastgah are used in both rhythmic and non-rhythmic. Result:
The results of this study revealed the brain activities for each of rhythmic and non-rhythmic versions of Homayoun Dastgah. The activated regions for non-rhythmic Homayoun contained: right and left Subcallosal Cortex, left Medial Frontal cortex, left anterior Cingulate Gyrus, left Frontal Pole and for rhythmic Homayoun contained: left Precentral Gyrus, left Precuneous Cortex, left anterior Supramarginal, left Superior Parietal Lobule, left Postcentral Gyrus. Also, we acquired amygdala area in both pieces of music. Discussion:
Based on arousal effects of rhythm and Damasio's somatic marker hypothesis, non-rhythmic Homayoun activates regions related to emotion and thinking while activity of rhythmic Homayoun is related to areas of movement and motion.
Maral Yeganehdoost, Morteza Pishnamazi, Mohammad Ali Oghabian,
Volume 3, Issue 4 (8-2012)
Abstract
The attempt to find out if someone is telling a lie has been of human's interest. One of the techniques which is believed to be efficient in future is fMRI (functional Magnetic Resonance Imaging), using which the changes of regional blood flow during the designed paradigm can be recorded. This method has been considered as a better technique for studying lie and deception. For investigating the neural network associated with lying and deception, a task needs to be designed in which participants are instructed to participate in a lie-like situation. In this article, frequently used tasks have been reviewed with their merits and demerits. In addition, a summary of involved neural networks related to lie and deception, according to previous studies, is provided. The goal in future studies is to allocate brain regions associated with lie and deception that are independent of features related to the chosen task.
Mehdi Behroozi, Mohammad Reza Daliri,
Volume 3, Issue 5 (9-2012)
Abstract
Functional magnetic resonance imaging (fMRI) has become the most popular method for imaging of brain functions. Currently, there is a large variety of software packages for the analysis of fMRI data, each providing many features for users. Since there is no single package that can provide all the necessary analyses for the fMRI data, it is helpful to know the features of each software package. In this paper, several software tools have been introduced and they have been evaluated for comparison of their functionality and their features. The description of each program has been discussed and summarized.
Hassan Morsheddost, Davud Asemani, Mahsa Alizadeh,
Volume 6, Issue 1 (2-2015)
Abstract
Introduction: Prior studies comparing Hemodynamic Response Function (HRF) in the young
and elderly adults based on fMRI data have reported inconsistent findings for brain vision and
motor regions in healthy aging. It is shown that the averaging method employed in all previous
works has caused this inconsistency. The averaging is so sensitive to outliers and noise. However,
fMRI data are obscured with a major contribution of noise particularly in the elderly case.
Methods: Deconvolution algorithm is here proposed for HRF extraction to achieve more
robustness against noise. In spite of earlier works, proposed deconvolution algorithm yields
compatible HRF results using either original or denoised fMRI data, though a large percentage
of selected active voxels change in the latter case. In the current study, event-related fMRI
data have been used for 18 subjects (8 young and 10 elderly adults) with a simple visual and
motor task of pressing a key with index in response to the visual presentation of the word tap.
Considering anatomically-defined vision and motor regions and preprocessing steps in FSL and
SPM, the activated voxels have been selected according to t-test for which HRF is estimated
using deconvolution method.
Results: Experimental results demonstrate that HRF peak amplitudes do not differ significantly
(p=0.8) in the vision region for the young and the elderly. In motor region, the HRF peak
significantly increases for the young compared to the elderly (p<0.03). Repeating the procedure
on the denoised fMRI data using MDL algorithm, the same results have been obtained.
Discussion: In this study, a comparative study has been realized on the hemodynamic
response properties associated with the young and the elderly adults on a simple visual
and motor task.
Peyman Hassani-Abharian, Habib Ganjgahi, Hosein Tabatabaei-Jafari, Mohammad Ali Oghabian, Azarakhsh Mokri, Hamed Ekhtiari,
Volume 6, Issue 4 (10-2015)
Abstract
Introduction: Drug craving could be described as a motivational state which drives drug
dependents towards drug seeking and use. Different types of self-reports such as craving feeling,
desire and intention, wanting and need, imagery of use, and negative affect have been attributed
to this motivational state. By using subjective self-reports for different correlates of drug craving
along with functional neuroimaging with cue exposure paradigm, we investigated the brain
regions that could correspond to different dimensions of subjective reports for heroin craving.
Methods: A total of 25 crystalline-heroin smokers underwent functional magnetic resonance
imaging (fMRI), while viewing heroin-related and neutral cues presented in a block-design task.
During trial intervals, subjects verbally reported their subjective feeling of cue induced craving
(CIC). After fMRI procedure, participants reported the intensity of their “need for drug use”
and “drug use imagination” on a 0-100 visual analog scale (VAS). Afterwards, they completed
positive and negative affect scale (PANAS) and desire for drug questionnaire (DDQ) with 3
components of “desire and intention to drug use,” “negative reinforcement,” and “loss of control.”
Results: The study showed significant correlation between “subjective feeling of craving” and
activation of the left and right anterior cingulate cortex, as well as right medial frontal gyrus.
Furthermore, the “desire and intention to drug use” was correlated with activation of the left
precentral gyrus, left superior frontal gyrus, and left middle frontal gyrus. Subjects also exhibited
significant correlation between the “need for drug use” and activation of the right inferior
temporal gyrus, right middle temporal gyrus, and right parahippocampal gyrus. Correlation
between subjective report of “heroin use imagination” and activation of the cerebellar vermis was
also observed. Another significant correlation was between the “negative affect” and activation
of the left precuneus, right putamen, and right middle temporal gyrus.
Discussion: This preliminary study proposes different neural correlates for various dimensions
of subjective craving self-reports. It could reflect multidimensionality of cognitive functions
corresponding with drug craving. These cognitive functions could represent their motivational
and affective outcomes in a single item “subjective craving feeling” or in self-reports with
multiple dissociable items, such as intention, need, imagination, or negative feeling. The new
psychological models of drug craving for covering various dimensions of subjective craving
self-reports based on their neurocognitive correspondence could potentially modify craving
assessments in addiction medicine.
Somayeh Maleki-Balajoo, Gholam-Ali Hossein-Zadeh, Hamid Soltanian-Zadeh, Hamed Ekhtiari,
Volume 7, Issue 4 (10-2016)
Abstract
Introduction: A fixed hemodynamic response function (HRF) is commonly used for functional magnetic resonance imaging (fMRI) analysis. However, HRF may vary from region to region and subject to subject. We investigated the effect of locally estimated HRF (in functionally homogenous parcels) on activation detection sensitivity in a heroin cue reactivity study.
Methods: We proposed a novel exploratory method for brain parcellation based on a probabilistic model to segregate the brain into spatially connected and functionally homogeneous components. Then, we estimated HRF and detected activated regions in response to an experimental task in each parcel using a joint detection estimation (JDE) method. We compared the proposed JDE method with the general linear model (GLM) that uses a fixed HRF and is implemented in FEAT (as a part of FMRIB Software Library, version 4.1).
Results: 1) Regions detected by JDE are larger than those detected by fixed HRF, 2) In group analysis, JDE found areas of activation not detected by fixed HRF. It detected drug craving a priori “regions-of-interest” in the limbic lobe (anterior cingulate cortex [ACC], posterior cingulate cortex [PCC] and cingulate gyrus), basal ganglia, especially striatum (putamen and
head of caudate), and cerebellum in addition to the areas detected by the fixed HRF method, 3) JDE obtained higher Z-values of local maxima compared to those obtained by fixed HRF.
Conclusion: In our study of heroin cue reactivity, our proposed method (that estimates HRF locally) outperformed the conventional GLM that uses a fixed HRF.
Masoomeh Kazemi, Hedayat Sahraei, Hamed Aliyari, Elaheh Tekieh, Mehdi Saberi, Hassan Tavacoli, Gholam Hossein Meftahi, Hossein Ghanaati, Maryam Salehi, Mostafa Hajnasrollah,
Volume 9, Issue 3 (5-2018)
Abstract
Introduction: The present research aimed to examine Visual Working Memory (VWM) test scores, as well as hormonal, genomic, and brain anatomic changes in the male rhesus macaques exposed to Extremely Low Frequency Magnetic Field (ELF-MF).
Methods: Four monkeys were exposed to two different ELF-MF frequencies: 1 Hz (control) and 12 Hz (experiment) with 0.7 µT (magnitude) 4 h/d for 30 consecutive days. Before and after the exposure, VWM test was conducted using a coated devise on a movable stand. About 10 mL of the animals’ blood was obtained from their femoral vain and used to evaluate their melatonin concentration. Blood lymphocytes were used for assaying the expressions of N-Methyl-D-aspartate NMDA-receptor genes expression before and after ELF exposure. Anatomical changes of hippocampus size were also assessed using MRI images.
Results: Results indicated that VWM scores in primates exposed to 12 Hz frequency ELF increased significantly. Plasma melatonin level was also increased in these animals. However, these variables did not change in the animals exposed to 1 Hz ELF. At last, expression of the NMDA receptors increased at exposure to 12 Hz frequency. However, hippocampal volume did not increase significantly in the animals exposed to both frequencies.
Conclusion: In short, these results indicate that ELF (12 Hz) may have a beneficial value for memory enhancement (indicated by the increase in VWM scores). This may be due to an increase in plasma melatonin and or expression of NMDA glutamate receptors. However, direct involvement of the hippocampus in this process needs more research.
Atiye Nazari, Hamid Alavimajd, Nezhat Shakeri, Mohsen Bakhshandeh, Elham Faghihzadeh, Hengameh Marzbani,
Volume 10, Issue 2 (3-2019)
Abstract
Introduction: In recent years, brain functional connectivity studies are extended using the advanced statistical methods. Functional connectivity is identified by synchronous activation in a spatially distinct region of the brain in resting-state functional Magnetic Resonance Imaging (MRI) data. For this purpose there are several methods such as seed-based correlation analysis based on temporal correlation between different Regions of Interests (ROIs) or between brain’s voxels of prior seed.
Methods: In the current study, test-retest Resting State functional MRI (rs-fMRI) data of 21 healthy subjects were analyzed to predict second replication connectivity map using first replication data. A potential estimator is “raw estimator” that uses the first replication data from each subject to predict the second replication connectivity map of the same subject. The second estimator, “mean estimator” uses the average of all sample subjects' connectivity to estimate the correlation map. Shrinkage estimator is made by shrinking raw estimator towards the average connectivity map of all subjects' first replicate. Prediction performance of the second replication correlation map is evaluated by Mean Squared Error (MSE) criteria.
Results: By the employment of seed-based correlation analysis and choosing precentral gyrus as the ROI over 21 subjects in the study, on average MSE for raw, mean and shrinkage estimator were 0.2169, 0.1118, and 0.1103, respectively. Also, percent reduction of MSE for shrinkage and mean estimator in comparison with raw estimator is 49.14 and 48.45, respectively.
Conclusion: Shrinkage approach has the positive effect on the prediction of functional connectivity. When data has a large between session variability, prediction of connectivity map can be improved by shrinking towards population mean.
Alireza Tabibkhooei, Maziar Azar, Ahmad Alagha, Javad Jahandideh, Feyzollah Ebrahimnia,
Volume 11, Issue 5 (9-2020)
Abstract
Introduction: The primary and definitive diagnosis of meningioma is based on histological assessment; however, employing imaging methods, like Magnetic Resonance Imaging (MRI) is very helpful to describe lesion’s characteristics. Accordingly, we decided to study the effect of imaging factors, like MRI data on the volume of hemorrhage (estimated blood loss) during meningioma surgery.
Methods: This was a cross-sectional, retrospective, and analytical study. The eligible patients were those with meningioma who were candidates for surgery. A total of 40 patients with meningioma were selected and assessed. The preoperative imaging findings were recorded, then estimated blood loss during the surgery was determined
Results: A reverse association was revealed between the degree of proximity to the nearest sinus and the rate of bleeding. Furthermore, the size of the mass was positively associated with the rate of bleeding; however, there was no significant correlation between the volume of bleeding and other parameters, including the degree of edema, the volume of mass, the site of the tumor in the brain, and the histological subtype of the tumor. The mean time of operation was strongly correlated with blood loss. The rate of bleeding was more expected in hypertensive versus normotensive patients.
Conclusion: Bleeding in various volumes could be a frequent finding in intracranial meningioma surgery. Overall, tumor size, the duration of surgery, a history of hypertension, and distance to the nearest sinuses were the main determinants for the severity of hemorrhage in patients undergoing meningioma surgery.
Seyed Amir Hossein Batouli, Valiallah Saba,
Volume 11, Issue 5 (9-2020)
Abstract
Introduction: Military missions involve stressful and life-threatening situations; however, soldiers should have a healthy cognition on the battlefield despite their high-stress levels. This is an ability that should be gained during prior military training. Successful and influential training is suggested to be associated with structural and functional improvements of the brain.
Methods: This study investigated the pattern of brain activation while observing videos relevant to life-threatening situations, in addition to brain structure. Accordingly, the obtained data were compared between 20 military members and 26 healthy controls. The study participants were all male, aged between 19 to 24 years, right-handed, studying BSc, and from the same socioeconomic status.
Results: The obtained data presented a larger volume in a total number of 1103 voxels of the brain (in 5 brain areas) in the military group. Furthermore, the military group suggested higher brain activation in the visual processing areas of the brain when observing real combat videos; however, this increment was mostly in the areas associated with motor processing and executive functions in the controls.
Conclusion: This study indicated that military training is associated with positive structural changes in the brain. Besides, it provided a different brain activation in response to stressful situations. These findings highlighted the importance of qualified military training.
Hamed Dehghani, Mohammad Ali Oghabian, Seyed Amir Hosein Batouli, Jalil Arab Kheradmand, Ali Khatibi,
Volume 11, Issue 6 (11-2020)
Abstract
Introduction: Functional magnetic resonance imaging (fMRI) methods have been used to study sensorimotor processing in the spinal cord. However, these techniques confront unwanted noises to the measured signal from the physiological fluctuations. In the spinal cord imaging, most of the challenges are consequences of cardiac and respiratory movement artifacts that are considered as significant sources of noise, especially in the thoracolumbar region. In this study, we investigated the effect of each source of physiological noise and their contribution to the outcome of the analysis of the blood-oxygen-level-dependent signal in the human thoracolumbar spinal cord.
Methods: Fifteen young healthy male volunteers participated in the study, and pain stimuli were delivered on the L5 dermatome between the two malleoli. Respiratory and cardiac signals were recorded during the imaging session, and the generated respiration and cardiac regressors were included in the general linear model for quantification of the effect of each of them on the task-analysis results. The sum of active voxels of the clusters was calculated in the spinal cord in three correction states (respiration correction only, cardiac correction only, and respiration and cardiac noise corrections) and analyzed with analysis of variance statistical test and receiver operating characteristic curve.
Results: The results illustrated that cardiac noise correction had an effective role in increasing the active voxels (Mean±SD= 23.46±9.46) compared to other noise correction methods. Cardiac effects were higher than other physiological noise sources
Conclusion: In summary, our results indicate great respiration effects on the lumbar and thoracolumbar spinal cord fMRI, and its contribution to the heartbeat effect can be a significant variable in the individual fMRI data analysis. Displacement of the spinal cord and the effects of this noise in the thoracolumbar and lumbar spinal cord fMRI results are significant and cannot be ignored.
Aslan Dizaji, Bruno Hebling Vieira, Mohmmad Reza Khodaei, Mahnaz Ashrafi, Elahe Parham, Gholam Ali Hossein-Zadeh, Carlos Ernesto Garrido Salmon, Hamid Soltanian Zadeh,
Volume 12, Issue 1 (1-2021)
Abstract
Human intelligence has always been a fascinating subject for scientists. Since the inception of Spearman’s general intelligence in the early 1900s, there has been significant progress towards characterizing different aspects of intelligence and its relationship with structural and functional features of the brain. In recent years, the invention of sophisticated brain imaging devices using Diffusion-Weighted Imaging (DWI) and functional Magnetic Resonance Imaging (fMRI) has allowed researchers to test hypotheses about neural correlates of intelligence in humans.This review summarizes recent findings on the associations of human intelligence with neuroimaging data. To this end, first, we review the literature that has related brain morphometry to intelligence. Next, we elaborate on the applications of DWI and resting-state fMRI on the investigation of intelligence. Then, we provide a survey of literature that has used multimodal DWI-fMRI to shed light on intelligence. Finally, we discuss the state-of-the-art of individualized prediction of intelligence from neuroimaging data and point out future strategies. Future studies hold promising outcomes for machine learning-based predictive frameworks using neuroimaging features to estimate human intelligence.
Mahdieh Karami, Jafar Mehvari Habibabadi, Reza Nilipour, Majid Barekatain, William D. Gaillard, Hamid Soltanian-Zadeh,
Volume 12, Issue 2 (3-2021)
Abstract
Introduction: about 20% to 30% of patients with epilepsy are diagnosed with drug-resistant epilepsy and one third of these are candidates for epilepsy surgery. Surgical resection of the epileptogenic tissue is a well-established method for treating patients with intractable focal epilepsy. Determining language laterality and locality is an important part of a comprehensive epilepsy program before surgery. Functional Magnetic Resonance Imaging (fMRI) has been increasingly employed as a non-invasive alternative method for the Wada test and cortical stimulation. Sensitive and accurate language tasks are essential for any reliable fMRI mapping.
Methods: The present study reviews the methods of presurgical fMRI language mapping and their dedicated fMRI tasks, specifically for patients with epilepsy.
Results: Different language tasks including verbal fluency are used in fMRI to determine language laterality and locality in different languages such as Persian. there are some considerations including the language materials and technical protocols for task design that all presurgical teams should take into consideration.
Conclusion: Accurate presurgical language mapping is very important to preserve patients language after surgery. This review was the first part of a project for designing standard tasks in Persian to help precise presurgical evaluation and in Iranian PWFIE.
Fatemeh Yavari, Pardis Oliazadeh, Meisam Radfar, Mohsen Foroughipour, Karim Nikkhah, Alireza Heidari Bakavoli, Morteza Saeidi,
Volume 12, Issue 2 (3-2021)
Abstract
Introduction: Fingolimod is the first confirmed oral immune-modulator to treat Relapsing-Remitting Multiple Sclerosis (RRMS). This study aimed to investigate the safety and efficacy of fingolimod therapy in Iranian patients with RRMS.
Methods: In our trial, 50 patients resistant to conventional interferon therapy were assigned to receive fingolimod 0.5 mg per day for 12 months. The number of Dadolinium (Gd)-enhanced lesions, enlarged T2 lesions, and relapses over 12 months were considered as endpoints and compared to baseline. Liver biochemical evaluations and lymphocyte count were done at baseline and in months 3, 6, and 12 of the study. Patients were also monitored for possible cardiovascular events within the first 24 h and other side effects routinely.
Results: Among the patients who completed the trial, the number of Gd-enhanced and enlarged T2 lesions over 12 months significantly decreased (P=0.03 and P<0.001, respectively). The proportion of relapse-free patients was higher compared to the onset of fingolimod administration. There were no significant alterations in the Expanded Disability Status Scale (EDSS) scores. A slight, transient increase was recorded in liver enzymes among the participants. Lymphocyte count reduced by 61% at month 1 and displayed a gradual increase until month 12. No bradycardia and macular edema were recorded.
Conclusion: These findings indicate an effective first-line fingolimod therapy for the first time in Iranian patients with RRMS. The decrease in the number of new attacks and the amelioration of MRI lesions were the benefits of fingolimod therapy, suggesting that it is preferred to other medicines to treat RRMS in Iran.
Nasim Sattari, Fariborz Faeghi, Babak Shekarchi, Mohammad Hossein Heidari,
Volume 13, Issue 2 (3-2022)
Abstract
Introduction: In this study, we intend to determine the correlation between the thickness of the cerebral cortex and the severity of the cognitive disorder in Alzheimer disease (AD).
Methods: A total of 20 (14 women and 6 men) patients diagnosed with AD with a Mean age of 72.95 years, and 10 (7 women and 3 men) cognitively normal (CN) subjects with a Mean age of 70.50 years were included in the study. Of the AD patient and CN subjects, 70% were female, and 30% were male. All individuals underwent 1.5 T Magnetic resonance imaging (MRI). The MRI scanning protocol included 3D MPRAGE (3D-T1W) sequence. All images were analyzed using Freesurfer v5.3, and then the brain cortical thickness in 7 cortical areas (inferior temporal, middle temporal, superior temporal, parahippocampal, pars triangularis, rostral middle frontal, and superior frontal) was calculated.
Results: The analysis of covariance (ANCOVA) was conducted to compare the mean thickness of each region between the patient and the control group. There was a significant difference in the mean cortical thickness in all regions. In all cases, the mean cortical thickness in CN subjects was greater than in AD patients. However, the mean thickness of pars triangularis left hand in CN subjects was not significantly greater than that in AD patients. The receiver operating characteristic system (ROC) was designed to evaluate the predictive power of the patients and the healthy people. We have selected a thousand cut-off points from 1.5 to 3.5 mm for cortical thickness. When the cut-off points were within 2.276878–2.299680 mm in the left hemisphere, Youden’s index was maximum. The sensitivity and specificity, in this case, were 80%. Also, when the cut-off points were within the range of 2.263278–2.282278 mm in the right hemisphere, the sensitivity and specificity were 90% and 80%, respectively.
Conclusion: This study demonstrates the importance of quantifying the cortical thickness changes in the early diagnosis of AD. In addition, examining the pattern of changes and quantifying the reduction in the thickness of the cortex is a crucial tool for displaying the local and global atrophy of the brain. Also, this pattern can be used as an alternative marker for the diagnosis of dementia. Finally, to the best of our knowledge, our study is the first to report finding on the cortical thickness that would help the clinician have a better differential diagnosis. Also, this study has checked the possibility of early diagnosis of the disease.
Hamed Aliyari, Hedayat Sahraei, Sahar Gholabi, Mohammad Bagher Menhaj, Masoomeh Kazemi, Seyed Hossein Hosseinian,
Volume 13, Issue 4 (7-2022)
Abstract
Introduction: Living near high-voltage power lines and exposure to high-frequency electromagnetic fields (EMFs) is a potentially serious hazard to animal and human health. The present study was conducted to evaluate the effect of high-frequency EMFs from simulated high-voltage electric towers on cognitive, anatomical, and biological changes in the male macaque.
Methods: In this study, two Rhesus macaque were recruited, one experimental and one control. The experimental subject was exposed to EMFs from 3 kV/m simulated electric towers with a specific protocol and the control subject was tested without irradiation (4h per day, for 30 days). All required tests were performed before and after the intervention on experimental and control monkeys. The anatomical alternation of the prefrontal area (PFA) was measured by MRI images. All tests were performed on irradiated and control animals before and after the intervention and the results were compared between irradiated and control animals.
Results: The results of the present study indicated increased white blood cell counts after high-frequency EMFs irradiation. Also, the red blood cell counts showed a decreasing trend after irradiation. The plasma adrenaline level increased after irradiation. Besides, the blood glucose levels increased after irradiation. The PFA was different before and after the irradiation. Moreover, some behavioral disorders, such as fatigue, drowsiness, anorexia, and insomnia were observed after irradiation.
Conclusion: The results of biological tests and MRI showed an elevated risk of immunodeficiency disorders, weakness, and behavioral disorders. People who live or work near high-voltage electric towers with high-frequency EMFs are warned.
Chan-A Park, Yeong-Bae Lee, Chang-Ki Kang,
Volume 13, Issue 6 (11-2022)
Abstract
Introduction: This study aimed to assess the effect of controlled mouth breathing during the resting state using functional magnetic resonance imaging (fMRI).
Methods: Eleven subjects participated in this experiment in which the controlled “Nose” and “Mouth” breathings of 6 s respiratory cycle were performed with a visual cue at 3T MRI. Voxel-wise seed-to-voxel maps and whole-brain region of interest (ROI)-to-ROI connectome maps were analyzed in both “Nose>Mouth” and “Mouth>Nose” contrasts.
Results: As a result, there were more connection pairs in the “Mouth” breathing condition, i.e., 14 seeds and 14 connecting pairs in the “Mouth>Nose” contrast, compared to 7 seeds and 4 connecting pairs in the “Nose>Mouth” contrast (false discovery rate [FDR] of P<0.05).
Conclusion: The present study demonstrated that mouth breathing with controlled respiratory cycles could significantly induce alterations in functional connectivity in the resting-state network, suggesting that it can differently affect resting brain function; in particular, the brain can hardly rest during mouth breathing, as opposed to conventional nasal breathing.
