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Abstract: Recognition and processing of emotional facial expression are crucial for social behavior and employ higher-order cognitive and visual working processes. In neuropsychiatric disorders, impaired emotion recognition most frequently concerned three specific emotions, i.e., anger, fear, and disgust. As incorrect processing of (neutral) facial stimuli per se might also underlie deficits in the recognition of emotional facial expressions, we aimed to assess all these aspects in one experiment. We therefore report here a functional magnetic resonance imaging (fMRI) paradigm for parallel assessment of the neural correlates of both the recognition of neutral faces and the three clinically most relevant emotions for future use in patients with neuropsychiatric disorders. FMRI analyses were expanded through comparisons of the emotional conditions with each other. The differential insights resulting from these two analyses strategies are compared and discussed. 30 healthy participants (21 F/9 M; age 36.3±14.3, 17–66years) underwent fMRI and behavioral testing for non-emotional and emotional face recognition. Recognition of neutral faces elicited activation in the fusiform gyri. Processing angry faces led to activation in left middle and superior frontal gyri and the anterior cingulate cortex. There was considerable heterogeneity regarding the fear versus neutral contrast, resulting in null effects for this contrast. Upon recognition of disgust, activation was noted in bilateral occipital, in the fronto-orbital cortex and in the insula. Analyzing contrasts between emotional conditions showed similar results (to those of contrasting with reference conditions) for separated emotional network patterns. We demonstrate here that our paradigm reproduces single aspects of separate previous studies across a cohort of healthy subjects, irrespective of age. Our approach might prove useful in future studies of patients with neurologic disorders with potential effect on emotion recognition. [Copyright &y& Elsevier]

Background: Lesion dissemination in time and space represents a key feature and diagnostic marker of multiple sclerosis (MS). The correlation between magnetic resonance imaging (MRI) lesion load and disability is only modest, however. Strategic lesion location might at least partially account for this ‘clinico-radiologic paradox’.Objectives: Here we used a non-parametric permutation-based approach to map lesion location probability based on MS lesions identified on T2-weighted MRI. We studied 121 patients with clinically isolated syndrome, relapsing–remitting or secondary progressive MS and correlated these maps to assessments of neurologic and cognitive functions.Results: The Expanded Disability Status Scale correlated with bilateral periventricular lesion location (LL), and sensory and coordination functional system deficits correlated with lesion accumulation in distinct anatomically plausible regions, i.e. thalamus and middle cerebellar peduncule. Regarding cognitive performance, decreased verbal fluency correlated with left parietal LL comprising the putative superior longitudinal fascicle. Delayed spatial recall correlated with _amygdalar, _left frontal and parietal LL. Delayed selective reminding correlated with bilateral frontal and temporal LL. However, only part of the spectrum of cognitive and neurological problems encountered in our cohort could be explained by specific lesion location.Conclusions: Lesion probability mapping supports the association of specific lesion locations with symptom development in MS, but only to limited extent. [ABSTRACT FROM AUTHOR]

Background: Cognitive deficits are frequent in multiple sclerosis (MS) and have been associated with morphologic brain changes. Less information exists on their extent and relation to MRI findings in clinically isolated syndrome (CIS). It is also unclear if structural changes as detected by magnetization transfer (MT) imaging may provide an additional explanation for cognitive dysfunction.Objective: To analyse the extent of cognitive deficits and their relation to MRI metrics including MT imaging in CIS compared to relapsing-remitting MS (RRMS).Methods: Forty-four CIS and 80 RRMS patients underwent the Brief Repeatable Battery of Neuropsychological Tests (BRB-N) and a 3 T MRI scan.Results: BRB-N subtests revealed similar results in CIS and RRMS. Impaired mental processing speed was most prevalent in both groups (CIS 13.6%; RRMS 16.3%) and thus served for correlation with MRI metrics. Using stepwise linear regression analyses, the strongest predictor for decreased mental processing speed was normalized cortex volume (p < 0.001) followed by T2-lesion load (p < 0.05) in RRMS, whereas cortical MT ratio was the only MRI parameter associated with decreased mental processing speed in CIS (p < 0.005).Conclusion: Cognitive dysfunction occurs in CIS in a pattern similar to RRMS, with impaired mental processing speed being most prevalent. Cortical MT-ratio changes may be an early sign for tissue changes related to impaired mental processing speed in CIS while this association shifts to increased signs of cortical atrophy and lesion load in RRMS. [ABSTRACT FROM AUTHOR]

Background Increased iron deposition has been implicated in the pathophysiology of multiple sclerosis (MS), based on visual analysis of signal reduction on T2-weighted images. R2* relaxometry allows to assess brain iron accumulation quantitatively. Objective To investigate regional brain iron deposition in patients with a clinically isolated syndrome (CIS) or relapsing-remitting MS (RRMS) and its associations with demographical, clinical, and conventional magnetic resonance imaging (MRI) parameters. Methods We studied 69 patients (CIS, n = 32; RRMS, n = 37) with 3T MRI and analyzed regional R2* relaxation rates and their correlations with age, disease duration, disability, T2 lesion load, and normalized brain volumes. Results Basal ganglia R2* relaxation rates increased in parallel with age (r = 0.3-0.6; P < 0.01) and were significantly higher in RRMS than in CIS (P < 0.05). Using multivariate linear regression analysis, the rate of putaminal iron deposition was independently predicted by the patients' age, disease duration, and gray matter atrophy. Conclusions Quantitative assessment by R2* relaxometry suggests increased iron deposition in the basal ganglia of MS patients, which is associated with disease duration and brain atrophy. This technique together with long-term follow-up thus appears suited to clarify whether regional iron accumulation contributes to MS morbidity or merely reflects an epiphenomenon. [ABSTRACT FROM AUTHOR]