Keywords: fMRI Acquisition, fMRI (task based), fMRI motion

Motivation: Handling subject motion in fMRI is an important issue. Thus, it's ideal to correct motion as thoroughly as possible during data preprocessing. 
 

Goal(s): We aim to develop an algorithm that accurately detects precise motion corrupted measurements to efficiently correct motion.
 

Approach: Motion signal was obtained from the k-space data by calculating average squared difference between first measurement and successive measurements . Equation of threshold value to verify presence of motion was formulated. Lastly, the outliers in motion signal were detected using WLS(weighted least square) optimization framework.

Results: The proposed method successfully detects precise motion corrupted measurements automatically.

Impact: The proposed method can facilitate precise fMRI analysis by detecting motion corrupted measurements in advance to data preprocessing procedure and applying suitable corrections, which enables us to input less motion contaminated data from the early stages of fMRI data preprocessing.

Keywords: Functional Connectivity, fMRI (resting state), Tinnitus, sound therapy, fMRI, brain network, effective connectivity

Motivation: We hypothesize that the investigation of brain FC may serve as a foundational step in exploring EC. 

Goal(s): To enhance the precision of identifying effective connectivity between distinct brain regions. 

Approach: We adopts the actor-critic framework with an encoder-decoder model as the actor network. The encoder utilizes the Transformer model, and the decoder employs a bidirectional long-short-term memory (LSTM) network with attention. 

Results: Tinnitus patients were feature by enhanced information output of the motor network, somatosensory network, and the visual network. Effective treatment is featured by a similar pattern of FGEC network between tinnitus patients after treatment and the healthy controls. 

Impact: The pattern of FGEC network can be regarded as a direct evidence to indicate the effectiveness of sound therapy for tinnitus patients prior to treatment. 

Keywords: Functional Connectivity, fMRI (resting state), Obesity, Bariatric surgery

Motivation: Bariatric surgery can rapidly alter obese status, but its effects on resting state functional connectivity (rsFC) in obesity remain unclear. 

Goal(s): We examined the effects of bariatric surgery on rsFC between brain networks in obese patients using independent component analysis. 

Approach: Thirty obese patients underwent resting state fMRI scans before and after bariatric surgery. We used independent component analysis to analyze surgery-related rsFC changes. 

Results: Bariatric surgery improved rsFC of hVN-lFPN, hVN-SMN, AUN-pDMN, AUN-DAN, pVN-aDMN, pVN-SMN, pDMN-SN, aDMN-DAN, and SMN-DAN in obese patients. These results indicate that bariatric surgery induces functional reorganization of brain networks in obesity.

Impact: Bariatric surgery can rapidly alter obese status. Our study investigates the rsFC before and after bariatric surgery, results show that bariatric surgery induces functional reorganization of brain networks in obesity.

Keywords: Task/Intervention Based fMRI, Brain Connectivity, Transcutaneous Vagal Nerve Stimulation

Motivation: There is marked heterogeneity in transcutaneous vagal nerve stimulation (tVNS) based on the anatomical site (cervical/auricular), and the waveform parameters (fixed/variable frequency) of the stimulation. 

Goal(s): To explore the functional brain differences between cervical vagal nerve stimulation and auricular vagal nerve stimulation.

Approach: Ultra-high field functional neuroimaging is performed of the neural correlates of tVNS with disparate anatomical sites and electrical waveform characteristics during rest in healthy participants

Results: Auricular stimulation with a variable frequency was shown to result in a significant decrease of the BOLD response in the amygdala and insular cortex compared to sham stimulation. 

Impact: There exist multiple knowledge gaps in the use of tVNS, which hinders the advancement of tVNS applications. This explorative study has shown the differences in neuronal response of auricular and cervical stimulation with fixed and variable frequencies.

Keywords: Task/Intervention Based fMRI, Data Analysis, Neuroimaging AFNI

Motivation: Mathematical processes are widely studied using neuroimaging techniques.

Goal(s): However limited knowledge exists on neurofunctional correlates of distinct mathematical operations, in adolescent samples, as the majority of studies are with adults or children.

Approach: We examine for the first time, using fMRI, brain activity associated with complex addition, subtraction, multiplication, and division in adolescents.

Results: Our study demonstrates the engagement of fronto-parietal, cingulo-operclum networks, and the cerebellum in mathematical operations. Further, we shed light on brain regions not frequently discussed in models of mathematical cognition, including the left temporal gyrus and bilateral supplementary motor area (SMA), specific to complex subtraction and division.

Impact: Results of the study add new knowledge on a modeling mathematical processes in adolescents. Coordinates in stereotaxic space can serve as a benchmark for future research with neurodevelopmental disorders as well as for individuals exhibiting exceptional mathematical proficiency.

Keywords: Task/Intervention Based fMRI, Brain, Neuroimaging, Pediatrics, Personalised Medicine

Motivation: Typically, fMRI studies predominantly rely on group comparisons, often lacking direct applications at an individual subject level, whether for research or clinical purposes.

Goal(s): We aimed to unveil the power of fMRI studies using an fMRI experiment to highlight the brain’s area of abnormalities in a 9 years old child experiencing  severe reading impairment.

Approach: Three fMRI tasks were used to characterize different reading network sections that were compared to an age matched control group via Crawford-Howell t-test.

Results: The study subject showed a different activation pattern in the right insula, an area associated with reading comprehension.

Impact: fMRI experiments can compare and emphasize differences in brain function at an individual subject basis in comparison to a control population. This evidence suggests the potential use of fMRI as an informative tool within the precision medicine framework.

Keywords: fMRI Analysis, Head & Neck/ENT

Motivation: This study aimed to explore alterations in brain surface-based morphometry sulcal depth in patients with idiopathic tinnitus before and after 24 weeks of sound therapy.

Goal(s): This study aimed to explore alterations in brain surface-based morphometry sulcal depth in patients with idiopathic tinnitus before and after 24 weeks of sound therapy.

Approach: Thirty-three tinnitus patients underwent magnetic resonance imaging scans at baseline and after 24 weeks of sound therapy.  

Results: Compared to HCs, those in the tinnitus group at baseline had significantly lower sulcal depth in the left medial temporal cortex (MTC) and right somatosensory and motor cortex (SMC).

Impact: The remodeling of sulcal depth after sound therapy is an indicator for effective sound therapy.

Keywords: Functional Connectivity, fMRI (resting state), Functional connectivity;Postpartum women

Motivation: Resting-state functional connectivity can elucidate the brain intrinsic functional connectivity patterns of postpartum women, providing new evidence for functional plasticity in postpartum women.

Goal(s): Our goal is to explore functional connectivity patterns of postpartum women.

Approach: Postpartum women were imaged using rs-fMRI and compared with nonmothers by functional connectivity analysis.

Results: Brain functional remodeling does occur in the postpartum women, as evidenced by changes in intrinsic functional connectivity patterns.

Impact: We used rs-FC to demonstrate that brain functional placity in postpartum women during raising infants, providing new ideas and directions for studying the neural mechanisms of maternal behavior.

Keywords: Task/Intervention Based fMRI, Brain, fractional amplitude of low-frequency fluctuation, postpartum depression, acupuncture, left supramarginal gyrus

Motivation: Acupuncture has received increasing attention for the treatment of postpartum depression (PPD), but the biological mechanisms are unclear.

Goal(s): Our study focused on the mechanisms of acupuncture-induced changes in brain function in PPD and whether this correlates with improvements in clinical symptoms.

Approach: The PPD group underwent depression scale assessment and fMRI at baseline, after 8 weeks of acupuncture, comparing pre- and post-acupuncture data to the HPD cohort.

Results: The results showed a significant decrease in HAMD scores and a significant increase in fALFF values of SMG.L in the PPD group after needling, but no correlation was found between the two.

Impact: This article offers preliminary evidence for acupuncture's potential in treating postpartum depression and explores brain activity changes using neuroimaging. It has the potential to inspire further research on depression treatment and neural mechanisms, providing new insights for clinical practice.

Keywords: Biology, Models, Methods, Spectroscopy, Glutamate, GABA, MRS

Motivation: Current assumptions propose that rapid fluctuations in Glu levels are associated with its release from vesicles in response to an event-related stimulus. Therefore, there should be rapid changes in GABA and Glu in response to a short stimulus that will show local stimulus-induced inhibition and excitation. 

Goal(s): To quantify GABA and Glu levels following a brief visual stimulus lasting three seconds.

Approach: Single voxel ¹H-MRS was used to measure GABA (MEGA-PRESS) and Glx (PRESS) levels. Flickering checkerboard (3s) was used for stimulation.

Results: Both neurotransmitter levels showed increase in first seconds after stimulus presentation and following decrease to a basic level.

Impact: This study tests hypothesis regarding rapid neurotransmitter level changes induced by vesicular release in response to short stimuli. The findings from this research have the potential to offer novel insights and methodologies for investigating neural processes.

Keywords: Task/Intervention Based fMRI, Neuroscience, Looping Star, silent fMRI, auditory task fMRI, auditory processing

Motivation: The scan noise of Gradient-recalled echo echo-planar imaging (GRE-EPI) is a major confounding factor for auditory task fMRI.

Goal(s): This study evaluated a novel silent fMRI technique, "Looping Star," comparing it to the conventional GRE-EPI method.

Approach: A passive listening task consisting of a continuous stream of multilingual babble was applied for seven participants who underwent Looping Star and GRE-EPI scans respectively using similar scan parameters.

Results: Looping Star showed higher sensitivity in detecting activations in primary auditory areas and additional regions not identified by GRE-EPI.

Impact: The results indicate Looping Star's potential for more accurate and comprehensive auditory task fMRI studies due to reduced acoustic interference.

Keywords: Task/Intervention Based fMRI, fMRI, Schizophrenia, machine learning, MVPA, decision maiking, MRI, decoding, tasked-based fmri

Motivation: The neural mechanisms underlying motivation and pleasure deficits in schizophrenia have not yet been elucidated.

Goal(s): We aimed to develop a method to disentangle different aspects of value-based decision making to understand these deficits in schizophrenia.

Approach: We developed a novel fMRI task and combined it with machine learning approaches to effectively measure multiple components of value-based decision making.

Results: Our preliminary results revealed that patterns of brain activity in the value regions of the brain (ventromedial PFC and ventral striatum) are predictive of healthy individuals’ decisions; however, such patterns do not provide value representation to support decision making in schizophrenia.

Impact: Neural patterns in the value regions of the brain were shown to not represent value to support decision making in schizophrenia. These findings will provide targets for treatment developments for motivation and pleasure deficits in schizophrenia and other psychiatric conditions.

Keywords: Peripheral Nerves, fMRI (task based), Sensory, Touch, Social

Motivation: Touch is the first sensory modality to develop. C-tactile (CT) nerves in hairy skin are involved in slow/gentle touch, and social interactions. However, brain mechanisms processing the affective aspects of touch remain under-studied.

Goal(s): We characterised the network of brain regions supporting perception of affective touch.

Approach: 11-volunteers underwent fMRI at clinically relevant 3T field strengths while their arm was gently brushed and compared with brushing to remove a marker.

Results: We found a network of brain regions involved in affective touch processing including the posterior superior temporal sulcus (pSTS), inferior frontal gyrus (IFG), temporoparietal junction (TPJ).

Impact: This study characterises the brain network processing affective touch, critical given the central role of touch during development and its social function throughout the lifespan. It helps understanding brain responses in adults born pre-term, where experience of touch was interrupted/reduced.

Keywords: fMRI Analysis, fMRI (task based), hemodynamic response function, activation

Motivation: Sinusoid tracking has several important advantages over DFT to detect hemodynamic response (HRF). We propose only per voxel HRF estimation to detect activation. GLM globally assumes identical HRF over all voxels to detect activation. While the general contour of HRF is widely accepted, little is known about its variability in different brain regions.

Goal(s): Determine activation and HRF across whole brain simultaneously.

Approach: A periodic impulsive stimulus generates BOLD response. Sinusoid tracking returns seven-harmonic parameters required from BOLD signal. 

Results: HRF is reconstructed from these harmonics, and ratios of harmonic amplitudes define activation.

Impact: A custom sinusoid tracking method, which (unlike windowed DFT) imposes no restriction on sample rate, stimulus task frequency, and record length, can detect hemodynamic response function and fMRI activation simultaneously per voxel across the whole brain.

Keywords: fMRI Analysis, fMRI (task based), motor control

Motivation: There is a lack of understanding of the mechanisms of post-stroke motor recovery. To date, fMRI brings information which are not linked to the movement characteristics.

Goal(s): To investigate whether integration of kinematic in fMRI adds any value to the understanding of motor function.

Approach: A block designed motor-task-fMRI experiment coupled with real-time motion-tracking was performed on sixteen healthy subjects. Post-processing consisted of a group-level analysis comparing the regression of the BOLD signal with action-rest onsets, and with the flexion velocity vector.

Results: Using a wider cluster-size, kinematic approach allows retrieving regions found with conventional approach and additional regions involved in motor control.

Impact: Coupling of fMRI with kinematics provides additional information on motor function and motor control. Post-stroke motor recovery is subject to variability and is linked to motor control. Coupling both measurements could provide better understanding of motor recovery at the individual-level.

Keywords: fMRI Analysis, fMRI, Motor function

Motivation: To benefit patients who needs presurgical mapping of tongue motor areas but have limited tb-fMRI.

Goal(s): To create a probabilistic tongue motor atlas and evaluate its use for guiding rs-fMRI seed-based correlation (SBC) analysis.

Approach: Presurgical tb-fMRI of 30 brain tumor patients were used to create the atlas. This atlas was transferred to a different set of patients’ individual space for guiding rs-fMRI analysis. Locations of functional connectivity detected in the ipsilateral hemisphere were compared with tb-fMRI results.

Results: A tongue motor atlas was developed, which can effectively guide the rs-fMRI analysis with results similar to when seeding based on the tb-fMRI activation.

Impact: The probabilistic functional atlas enables automated seed-based analysis for rs-fMRI localization of tongue motor areas in patients undergoing brain tumor resection. It also provides a functional localizer which can be used for various quantitative image analyses of tongue motor areas.