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Functional connectivity analysis is a common approach to the characterization of brain function. While studies of functional connectivity have predominantly focused on resting‐state fMRI, naturalistic paradigms, such as movie watching, are increasingly being used. This ecologically valid, yet relatively unconstrained acquisition state has been shown to improve subject compliance and, potentially, enhance individual differences. However, unlike the reliability of resting‐state functional connectivity, the reliability of functional connectivity during naturalistic viewing has not yet been fully established. The current study investigates the intra‐session reliability of functional connectivity during naturalistic viewing sessions to extend its understanding. Using fMRI data of 24 subjects measured at rest as well as during six naturalistic viewing conditions, we quantified the split‐half reliability of each condition, as well as cross‐condition reliabilities. We find that intra‐session reliability is relatively high for all conditions. While cross‐condition reliabilities are higher for pairings of two naturalistic viewing conditions, split‐half reliability is highest for the resting state. Potential sources of variability across the conditions, as well as the strengths and limitations of using intra‐session reliability as a measure in naturalistic viewing, are discussed. By enhancing the understanding of the reliability of naturalistic fMRI, our study supports future research that relates data measured during this increasingly popular experimental condition to behavioral or clinical characteristics. It demonstrates that the intra‐session reliability of functional connectivity is comparably high during six naturalistic viewing conditions and rest, includes a discussion of potential sources of variability, and a comparison across four anatomical atlases. [ABSTRACT FROM AUTHOR]

Neuroplasticity and brain reorganization associated with positive outcomes of multidisciplinary rehabilitation in progressive multiple sclerosis: a fMRI study. Keywords: fMRI; multiple sclerosis; open access; data report; neurorehabilitation EN fMRI multiple sclerosis open access data report neurorehabilitation 1 6 6 06/05/21 20210528 NES 210528 1. Open Access: The Effect of Neurorehabilitation on Multiple Sclerosis - Unlocking the Resting-State fMRI Data FMRI, multiple sclerosis, open access, data report, neurorehabilitation. [Extracted from the article]

This study analyzes how people's attitudes to the European refugee crisis (ERC) correspond to selected psychological state and trait measures and impact the neural processing of media images of refugees. From a large pool of respondents, who filled in an online xenophobia questionnaire, we selected two groups (total N = 38) with the same socio-demographic background, but with opposite attitudes toward refugees. We found that a negative attitude toward refugees (high xenophobia - HX) was associated with a significantly higher conscientiousness score and with a higher trait aggression and hostility, but there was no group effect connected with empathy, fear, and anxiety measures. At the neural level we found that brain activity during the presentation of ERC stimuli is affected by xenophobic attitudes—with more xenophobic subjects exhibiting a higher BOLD response in the left fusiform gyrus. However, while the fMRI results demonstrate increased attention and vigilance toward ERC-related stimuli in the HX group, they do not show differentiated patterns of brain activity associated with perception of dehumanized outgroup. [ABSTRACT FROM AUTHOR]

Functional MR imaging (fMRI) belongs already longer than two decades between methods used for the investigation of the human brain but also for monitoring of functional changes related to pathological processes. This article shortly explains physical and physiological basis of fMRI methods and shows its advantages and limitations. Also, various types of fMRI data acquisition and evaluation are discussed including their benefits as well as restrictions. Using several examples, different approach to fMRI application is demonstrated beginning with traditional visualization of activated regions to more modern way of investigation of the brain network connectivity. This article is not a survey of published results in fMRI field but rather it should help to reader with orientation in entire issues concerning of fMRI including some new trends in this region. [ABSTRACT FROM AUTHOR]

Abstract: Spinal cord stimulation (SCS) consisting of electrical stimulation of the dorsal spinal cord using epidural electrodes has been shown to relieve chronic neuropathic pain. To analyze the cerebral activation patterns related to SCS, and to evaluate the effects of SCS on the processing of acute experimental pain, we performed functional magnetic resonance imaging (fMRI) on eight patients suffering from failed back surgery syndrome who were also being treated with SCS for severe pain in their legs and lower back. Three types of stimulation were used, each lasting 36s: (i) SCS, (ii) heat pain (HP) applied to the leg affected by neuropathic pain, and (iii) simultaneous HP and SCS. During SCS, we found increased activation of the medial primary sensorimotor cortex somatotopically corresponding to the foot and/or perineal region, contralateral posterior insula, and the ipsilateral secondary somatosensory cortex (S2). Decreased activation was seen in the bilateral primary motor cortices and the ipsilateral primary somatosensory cortex corresponding to the shoulder, elbow and hand. Compared to separately presented HP and SCS, simultaneous HP and SCS showed statistically significant activation of the bilateral inferior temporal cortex and the ipsilateral cerebellar cortex. The activation of the primary motor cortex, insula and S2 during SCS may directly interfere with the processing of neuropathic pain. When SCS is associated with heat pain, the paralimbic association cortex and cerebellum show activation exceeding the sum of activations resulting from separate SCS and heat pain stimulation. The explanation of this could possibly rest with the continuous comparisons of simultaneous pain and somatosensory sensations occurring in a single dermatome. [Copyright &y& Elsevier]

Background and purpose Methods Results Conclusions Cognitive impairment (CI) in multiple sclerosis (MS) is associated with bidirectional changes in resting‐state centrality measures. However, practicable functional magnetic resonance imaging (fMRI) biomarkers of CI are still lacking. The aim of this study was to assess the graph‐theory‐based degree rank order disruption index (kD) and its association with cognitive processing speed as a marker of CI in patients with MS (PwMS) in a secondary cross‐sectional fMRI analysis.Differentiation between PwMS and healthy controls (HCs) using kD and its correlation with CI (Symbol Digit Modalities Test) was compared to established imaging biomarkers (regional degree, volumetry, diffusion‐weighted imaging, lesion mapping). Additional associations were assessed for fatigue (Fatigue Scale for Motor and Cognitive Functions), gait and global disability.Analysis in 56 PwMS and 58 HCs (35/27 women, median age 45.1/40.5 years) showed lower kD in PwMS than in HCs (median −0.30/−0.06, interquartile range 0.55/0.54; p = 0.009, Mann–Whitney U test), yielding acceptable yet non‐superior differentiation (area under curve 0.64). kD and degree in medial prefrontal cortex (MPFC) correlated with CI (kD/MPFC Spearman's ρ = 0.32/−0.45, p = 0.019/0.001, n = 55). kD also explained fatigue (ρ = −0.34, p = 0.010, n = 56) but neither gait nor disability.kD is a potential biomarker of CI and fatigue warranting further validation. [ABSTRACT FROM AUTHOR]

In this study, we use separate eye-tracking measurements and functional magnetic resonance imaging to investigate the neuronal and behavioral response to painted portraits with direct versus averted gaze. We further explored modulatory effects of several painting characteristics (premodern vs modern period, influence of style and pictorial context). In the fMRI experiment, we show that the direct versus averted gaze elicited increased activation in lingual and inferior occipital and the fusiform face area, as well as in several areas involved in attentional and social cognitive processes, especially the theory of mind: angular gyrus/temporo-parietal junction, inferior frontal gyrus and dorsolateral prefrontal cortex. The additional eye-tracking experiment showed that participants spent more time viewing the portrait's eyes and mouth when the portrait's gaze was directed towards the observer. These results suggest that static and, in some cases, highly stylized depictions of human beings in artistic portraits elicit brain activation commensurate with the experience of being observed by a watchful intelligent being. They thus involve observers in implicit inferences of the painted subject's mental states and emotions. We further confirm the substantial influence of representational medium on brain activity. [ABSTRACT FROM AUTHOR]