Multi-modal magnetic resonance imaging in the acute and sub-acute phase of mild traumatic brain injury: can we see the difference?

Advanced magnetic resonance imaging (MRI) methods were shown to be able to detect the subtle structural consequences of mild traumatic brain injury (mTBI). The objective of this study was to investigate the acute structural alterations and recovery after mTBI, using diffusion tensor imaging (DTI) to reveal axonal pathology, volumetric analysis, and susceptibility weighted imaging (SWI) to detect microhemorrhage. Fourteen patients with mTBI who had computed tomography with negative results underwent MRI within 3 days and 1 month after injury. High resolution T1-weighted imaging, DTI, and SWI, were performed at both time points. A control group of 14 matched volunteers were also examined following the same imaging protocol and time interval. Tract-Based Spatial Statistics (TBSS) were performed on DTI data to reveal group differences. T1-weighted images were fed into Freesurfer volumetric analysis. TBSS showed fractional anisotropy (FA) to be significantly (corrected p<0.05) lower, and mean diffusivity (MD) to be higher in the mTBI group in several white matter tracts (FA=40,737; MD=39,078 voxels) compared with controls at 72 hours after injury and still 1month later for FA. Longitudinal analysis revealed significant change (i.e., normalization) of FA and MD over 1 month dominantly in the left hemisphere (FA=3408; MD=7450 voxels). A significant (p<0.05) decrease in cortical volumes (mean 1%) and increase in ventricular volumes (mean 3.4%) appeared at 1 month after injury in the mTBI group. SWI did not reveal microhemorrhage in our patients. Our findings present dynamic micro- and macrostructural changes occurring in the acute to sub-acute phase in mTBI, in very mildly injured patients lacking microhemorrhage detectable by SWI. These results underscore the importance of strictly defined image acquisition time points when performing MRI studies on patients with mTBI

Emotional Intelligence Not Only Can Make Us Feel Negative, but Can Provide Cognitive Resources to Regulate It Effectively: An fMRI Study

Neuroscientists have formulated the model of emotional intelligence (EI) based on brain imaging findings of individual differences in EI. The main objective of our study was to operationalize the advantage of high EI individuals in emotional information processing and regulation both at behavioral and neural levels of investigation. We used a self-report measure and a cognitive reappraisal task to demonstrate the role of EI in emotional perception and regulation. Participants saw pictures with negative or neutral captions and shifted (reappraised) from negative context to neutral while we registered brain activation. Behavioral results showed that higher EI participants reported more unpleasant emotions. The Utilization of emotions scores negatively correlated with the valence ratings and the subjective difficulty of reappraisal. In the negative condition, we found activation in hippocampus (HC), parahippocampal gyrus, cingulate cortex, insula and superior temporal lobe. In the neutral context, we found elevated activation in vision-related areas and HC. During reappraisal (negative-neutral) condition, we found activation in the medial frontal gyrus, temporal areas, vision-related regions and in cingulate gyrus. We conclude that higher EI is associated with intensive affective experiences even if emotions are unpleasant. Strong skills in utilizing emotions enable one not to repress negative feelings but to use them as source of information. High EI individuals use effective cognitive processes such as directing attention to relevant details; have advantages in allocation of cognitive resources, in conceptualization of emotional scenes and in building emotional memories; they use visual cues, imagination and executive functions to regulate negative emotions effectively

Changes of migraine-related white matter hyperintensities after 3 years: A longitudinal MRI study

OBJECTIVE/BACKGROUND The aim of this longitudinal study was to investigate changes of migraine-related brain white matter hyperintensities 3 years after an initial study. Baseline quantitative magnetic resonance imaging (MRI) studies of migraine patients with hemispheric white matter hyperintensities performed in 2009 demonstrated signs of tissue damage within the hyperintensities. The hyperintensities appeared most frequently in the deep white matter of the frontal lobe with a similar average hyperintensity size in all hemispheric lobes. Since in this patient group the repeated migraine attacks were the only known risk factors for the development of white matter hyperintensities, the remeasurements of migraineurs after a 3-year long follow-up may show changes in the status of these structural abnormalities as the effects of the repeated headaches. METHODS The same patient group was reinvestigated in 2012 using the same MRI scanner and acquisition protocol. MR measurements were performed on a 3.0-Tesla clinical MRI scanner. Beyond the routine T1-, T2-weighted, and fluid-attenuated inversion recovery imaging, diffusion and perfusion-weighted imaging, proton magnetic resonance spectroscopy, and T1 and T2 relaxation time measurements were also performed. Findings of the baseline and follow-up studies were compared with each other. RESULTS The follow-up proton magnetic resonance spectroscopy studies of white matter hyperintensities showed significantly decreased N-acetyl-aspartate (median values 8.133 vs 7.153 mmol/L, P=.009) and creatine/phosphocreatine (median values 4.970 vs 4.641 mmol/L, P=.015) concentrations compared to the baseline, indicating a more severe axonal loss and glial hypocellularity with decreased intracellular energy production. The diffusion values, the T1 and T2 relaxation times, and the cerebral blood flow and volume measurements presented only mild changes between the studies. The number (median values 21 vs 25, P<.001) and volume (median values 0.896 vs 1.140 mL, P<.001) of hyperintensities were significantly higher in the follow-up study. No changes were found in the hemispheric and lobar distribution of hyperintensities. An increase in the hyperintensity size of preexisting lesions was much more common than a decrease (median values 14 vs 5, P=.004). A higher number of newly developed hyperintensities were detected than disappeared ones (130 vs 22), and most of them were small (<.034 mL). Small white matter hyperintensities in patients with a low migraine attack frequency had a higher chance to disappear than large white matter hyperintensities or white matter hyperintensities in patients with a high attack frequency (coefficient: -0.517, P=.034). CONCLUSIONS This longitudinal MRI study found clinically silent brain white matter hyperintensities to be predominantly progressive in nature. The absence of a control group precludes definitive conclusions about the nature of these changes or if their degree is beyond normal aging

Age-related decline in circulating IGF-1 associates with impaired neurovascular coupling responses in older adults

AbstractImpairment of moment-to-moment adjustment of cerebral blood flow (CBF) to the increased oxygen and energy requirements of active brain regions via neurovascular coupling (NVC) contributes to the genesis of age-related cognitive impairment. Aging is associated with marked deficiency in the vasoprotective hormone insulin-like growth factor-1 (IGF-1). Preclinical studies on animal models of aging suggest that circulating IGF-1 deficiency is causally linked to impairment of NVC responses. The present study was designed to test the hypotheses that decreases in circulating IGF-1 levels in older adults also predict the magnitude of age-related decline of NVC responses. In a single-center cross-sectional study, we enrolled healthy young (n = 31, 11 female, 20 male, mean age: 28.4 + / − 4.2 years) and aged volunteers (n = 32, 18 female, 14 male, mean age: 67.9 + / − 4.1 years). Serum IGF-1 level, basal CBF (phase contrast magnetic resonance imaging (MRI)), and NVC responses during the trail making task (with transcranial Doppler sonography) were assessed. We found that circulating IGF-1 levels were significantly decreased with age and associated with decreased basal CBF. Age-related decline in IGF-1 levels predicted the magnitude of age-related decline in NVC responses. In conclusion, our study provides additional evidence in support of the concept that age-related circulating IGF-1 deficiency contributes to neurovascular aging, impairing CBF and functional hyperemia in older adults.</jats:p

Disconnection Mechanism and Regional Cortical Atrophy Contribute to Impaired Processing of Facial Expressions and Theory of Mind in Multiple Sclerosis: A Structural MRI Study

Successful socialization requires the ability of understanding of others' mental states. This ability called as mentalization (Theory of Mind) may become deficient and contribute to everyday life difficulties in multiple sclerosis. We aimed to explore the impact of brain pathology on mentalization performance in multiple sclerosis. Mentalization performance of 49 patients with multiple sclerosis was compared to 24 age- and gender matched healthy controls. T1- and T2-weighted three-dimensional brain MRI images were acquired at 3Tesla from patients with multiple sclerosis and 18 gender- and age matched healthy controls. We assessed overall brain cortical thickness in patients with multiple sclerosis and the scanned healthy controls, and measured the total and regional T1 and T2 white matter lesion volumes in patients with multiple sclerosis. Performances in tests of recognition of mental states and emotions from facial expressions and eye gazes correlated with both total T1-lesion load and regional T1-lesion load of association fiber tracts interconnecting cortical regions related to visual and emotion processing (genu and splenium of corpus callosum, right inferior longitudinal fasciculus, right inferior fronto-occipital fasciculus, uncinate fasciculus). Both of these tests showed correlations with specific cortical areas involved in emotion recognition from facial expressions (right and left fusiform face area, frontal eye filed), processing of emotions (right entorhinal cortex) and socially relevant information (left temporal pole). Thus, both disconnection mechanism due to white matter lesions and cortical thinning of specific brain areas may result in cognitive deficit in multiple sclerosis affecting emotion and mental state processing from facial expressions and contributing to everyday and social life difficulties of these patients

Emotional Intelligence Not Only Can Make Us Feel Negative, but Can Provide Cognitive Resources to Regulate It Effectively: An fMRI Study

Neuroscientists have formulated the model of emotional intelligence (EI) based on brain imaging findings of individual differences in EI. The main objective of our study was to operationalize the advantage of high EI individuals in emotional information processing and regulation both at behavioral and neural levels of investigation. We used a self-report measure and a cognitive reappraisal task to demonstrate the role of EI in emotional perception and regulation. Participants saw pictures with negative or neutral captions and shifted (reappraised) from negative context to neutral while we registered brain activation. Behavioral results showed that higher EI participants reported more unpleasant emotions. The Utilization of emotions scores negatively correlated with the valence ratings and the subjective difficulty of reappraisal. In the negative condition, we found activation in hippocampus (HC), parahippocampal gyrus, cingulate cortex, insula and superior temporal lobe. In the neutral context, we found elevated activation in vision-related areas and HC. During reappraisal (negative-neutral) condition, we found activation in the medial frontal gyrus, temporal areas, vision-related regions and in cingulate gyrus. We conclude that higher EI is associated with intensive affective experiences even if emotions are unpleasant. Strong skills in utilizing emotions enable one not to repress negative feelings but to use them as source of information. High EI individuals use effective cognitive processes such as directing attention to relevant details; have advantages in allocation of cognitive resources, in conceptualization of emotional scenes and in building emotional memories; they use visual cues, imagination and executive functions to regulate negative emotions effectively.</jats:p

Neural correlates of Machiavellian strategies in a social dilemma task.

In spite of having deficits in various areas of social cognition, especially in mindreading, Machiavellian individuals are typically very successful in different tasks, including solving social dilemmas. We assume that a profound examination of neural structures associated with decision-making processes is needed to learn more about Machiavellians' abilities in exploiting other people. More specifically, we predicted that high-Mach people would show elevated activity in the brain areas involved in reward-seeking, anticipation of risky situations, and inference making. To test this hypothesis, we used an fMRI technique to examine individuals as they played the Trust Game. In accordance with our predictions, we found consistent activation in high-Machs' thalamus and anterior cingulate cortex (player 1), and dorsal anterior insula/inferior frontal gyrus (player 2). We suggest that Machiavellians conduct specific neural operations in social dilemma situations that make them successful in exploiting others. Machiavellians may have cognitive heuristics that enable them to make predictions about the future reward in a basically risky and unpredictable situation

A Miniature Optical Neuronavigation System for CT-Guided Stereotaxy

Background and Objective: Neuronavigation devices have progressed over the past 2 decades, but logistical limitations remain for many stereotactic procedures. We describe our technique and accuracy for a novel miniature optical tracking system which overcomes these limitations. Method: The minioptical tracking system uses a miniature video camera mounted on a rigid cannula to determine cannula location and orientation relative to a patient-attached sticker containing reference markers. A CT scan is used to register these markers to the anatomy and a user-selected target. A computer displays the cannula guidance information to the target. Bench testing was performed on 225 targets in a custom test phantom and additional testing was performed on 20 small targets in an anthropomorphic head phantom to determine the practical accuracy and workflow. Results: The phantom study demonstrated that 3-D navigation accuracy is 1.41 ± 0.53 mm. There was a 100% head phantom study success rate for the 20 small targets. Conclusions: The resulting accuracy data demonstrated good correlation with the CT data, and the clinical simulation workflow indicated its potential usefulness for common neurosurgical applications. Furthermore, this small-footprint tracking technology does not experience the traditional environmentally induced issues or the requirement of pin-based head fixation, allowing for use in the neurointensive care unit and the emergency department. © 2013 S. Karger AG, Basel