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C. Cerami,
A. Dodich,
N. Canessa,
C. Crespi,
S. Iannaccone,
M. Corbo,
C. Lunetta,
M. Consonni,
E. Scola, A. Falini,
S. F. Cappa
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ABSTRACT: Amyotrophic lateral sclerosis (ALS) is a multisystem condition, in which executive and/or behavioural symptoms can occur. Deficits of social cognition, including defective cognitive and emotional empathy, have been recently reported in ALS subjects. The neurostructural correlates of these disorders in ALS are still unknown. The aims of this study were to evaluate two components of empathy in non-demented ALS subjects, and to associate performance with regional grey-matter density using voxel-based morphometry (VBM). Twenty non-demented sporadic probable or definite ALS patients and 56 matched healthy controls (HC) participated in a non-verbal task requiring the attribution of emotional versus cognitive states to identify the correct ending of comic strips, compared with a control condition requiring identifying causal relationships devoid of social components. A subgroup of 14 ALS and 20 HC joined the VBM study. Results demonstrated that, compared with controls, ALS patients showed defective emotional empathy attribution, related with reduced grey-matter density in the anterior cingulate cortex and right inferior frontal gyrus. Our study provided evidence of a specific impairment of emotional empathy in ALS patients, reflecting neural damage in a limbic prefrontal network involved in emotional processing. Social cognition disorders may represent a marker of cognitive dysfunction in ALS.
Amyotroph Lateral Scler Frontotemporal Degener. 01/2013;
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M Filippi,
P Preziosa,
E Pagani,
M Copetti,
S Mesaros,
B Colombo,
Ma Horsfield, A Falini,
G Comi,
H Lassmann,
Ma Rocca
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ABSTRACT: BACKGROUND: Pathologic and magnetic resonance imaging (MRI) studies have shown that cortical lesions (CLs) are a frequent finding in multiple sclerosis (MS). OBJECTIVE: To quantify microstructural damage in CLs and normal appearing (NA) cortex in relapse-onset MS patients at different stages of the disease. METHODS: Brain double inversion recovery (DIR), diffusion tensor (DT) MRI and 3D T(1)-weighted scans were acquired from 35 relapsing-remitting (RR) patients, 23 secondary progressive (SP) patients, 12 benign (B) MS patients and 41 healthy controls (HC). Diffusivity values in CLs, cortex, white matter (WM) lesions and normal-appearing white matter (NAWM) were assessed. RESULTS: Compared to HC, MS patients had a significantly lower fractional anisotropy (FA) and higher mean diffusivity (MD) in the cortex and NAWM. CLs had higher FA vs HC cortex and vs patients' cortex. Compared to RRMS patients, SPMS patients had higher WM lesion volume, higher MD in the cortex, and more severe damage to the NAWM and WM lesions. Compared to SPMS patients, BMS patients had lower MD and FA of CLs. Damage in other compartments was similar between SPMS and BMS patients. Damage in CLs had a high power to discriminate BMS from SPMS (area under the curve: 79-91%), with high specificity (85%), sensitivity (100%) and accuracy (90%). CONCLUSIONS: Microstructural imaging features of CLs differ from those of WM lesions and are likely to reflect neuronal damage and microglial activation. The nature and extent of CL damage can be used to help distinguish the different MS clinical phenotypes.
Multiple Sclerosis 08/2012; · 4.26 Impact Factor
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M Filippi,
F Agosta,
G B Frisoni,
N De Stefano,
A Bizzi,
M Bozzali, A Falini,
M A Rocca,
S Sorbi,
C Caltagirone,
G Tedeschi
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ABSTRACT: Quantitative outcome variables in Alzheimer's disease (AD) are of interest because of their low longitudinal variability compared with that of repeated clinical and cognitive measurements. Conventional MR-based volumetry of structures within and beyond the medial temporal lobe has proven to be useful in the diagnostic work up of early AD patients, and measures of atrophy have the potential to monitor the efficacy of disease-modifying agents. The extensive application of new non-conventional MR-based techniques to the study of AD, such as proton magnetic resonance spectroscopic imaging, diffusion tensor MRI, and functional MRI, has undoubtedly improved our understanding of the pathophysiology of the disease, and might lead to the identification of additional useful markers of disease progression. This review summarizes the main results obtained from the application of conventional and non-conventional MRI in AD patients, and supports their more extensive use in studies of disease evolution and clinical trials.
Current Alzheimer research 04/2012; · 4.97 Impact Factor
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ABSTRACT: Wernicke’s encephalopathy (WE) is an acute or subacute syndrome that results from a deficiency in vitamin B1 (thiamine). The
syndrome is characterised by a classical triad of symptoms: nystagmus and ophthalmoplegia, mental-status changes, and unsteadiness
of stance and gait. When patients with WE are inappropriately treated with low doses of thiamine, mortality rates average
out at 20% and Korsakoff’s Psychosis develops in about 85% of survivors (Sechi and Serra in Lancet Neurol 6(5):442–455, 2007). We report the case of a patient with a pyloric sub-stenosis that developed a WE, and was treated with high doses of thiamine
showing after few days of treatment a great improvement of neurological and neuroradiological assessment, even though cognitive
impairment was still severe at discharge and at 6months follow-up.
KeywordsWernicke’s encephalopathy-Pyloric sub-stenosis-Thiamine therapy
Neurological Sciences 04/2012; 31(6):859-861. · 1.32 Impact Factor
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ABSTRACT: Magnetic resonance (MR) imaging is an extremely sensitive modality for detecting focal changes to the white matter (WM) in patients with multiple sclerosis (MS). For this reason, it has become an integral part of the diagnostic workup of patients with clinically isolated syndromes who are at risk of developing definite MS, and it is always recommended in patients with definite MS to confirm the diagnosis and monitor the disease course. Crucial to the use of MR imaging for diagnostic purposes is the identification of lesion features - in terms of site, shape and size - that may be considered suggestive or typical for MS, and thus help in the differential diagnosis with other neurological diseases with similar clinical presentation to MS. This need has led to the publication of several guidelines for characterising MS lesions on both dualecho (T2 and proton density) and T1-weighted sequences after administration of contrast material. Developments in clinical research into MS have highlighted the need to formulate a diagnosis as far as possible on the basis of objective and reproducible criteria. Currently, when making a clinical diagnosis and monitoring patients with suspected MS, neurologists and neuroradiologists make use of specific diagnostic criteria that have changed over the years and will probably continue to be updated. It is therefore crucial for radiologists to become familiar with these criteria in order to improve the quality of their diagnostic assessment. In patients with a definite diagnosis of MS, on the other hand, the main problem is to define standard procedures for monitoring the course of the disease and response to pharmacological treatments. even though no guidelines currently exist, it is possible to suggest some strategies to improve the assessment in this setting.
La radiologia medica 03/2012; · 1.44 Impact Factor
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F Agosta,
E Scola,
E Canu,
A Marcone,
G Magnani,
L Sarro,
M Copetti,
F Caso,
C Cerami,
G Comi,
S F Cappa, A Falini,
M Filippi
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ABSTRACT: White matter (WM) tract damage was assessed in patients with the behavioral variant frontotemporal dementia (bvFTD) and the 3 primary progressive aphasia (PPA) variants and compared with the corresponding brain atrophy patterns. Thirteen bvFTD and 20 PPA patients were studied. Tract-based spatial statistics and voxel-based morphometry were used. Patients with bvFTD showed widespread diffusion tensor magnetic resonance imaging (DT MRI) abnormalities affecting most of the WM bilaterally. In PPA patients, WM damage was more focal and varied across the 3 syndromes: left frontotemporoparietal in nonfluent, left frontotemporal in semantic, and left frontoparietal in logopenic patients. In each syndrome, DT MRI changes extended beyond the topography of gray matter loss. Left uncinate damage was the best predictor of frontotemporal lobar degeneration diagnosis versus controls. DT MRI measures of the anterior corpus callosum and left superior longitudinal fasciculus differentiated bvFTD from nonfluent cases. The best predictors of semantic PPA compared with both bvFTD and nonfluent cases were diffusivity abnormalities of the left uncinate and inferior longitudinal fasciculus. This study provides insights into the similarities and differences of WM damage in bvFTD and PPA variants. DT MRI metrics hold promise to serve as early markers of WM integrity loss that only at a later stage may be detectable by volumetric measures.
Cerebral Cortex 10/2011; · 6.54 Impact Factor
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ABSTRACT: Double inversion recovery (DIR) sequences have improved the detection of cortical lesions (CLs) in adult patients with multiple sclerosis (MS). We evaluated the presence and frequency of CLs in pediatric patients with relapsing-remitting MS (RRMS) in comparison to adult patients with MS with the same clinical phenotype.
Using a 3.0-T scanner, brain DIR, dual-echo, and 3-dimensional T1-weighted scans were acquired from 24 pediatric patients with RRMS, 15 adult patients with RRMS, and 10 pediatric healthy controls. CLs and white matter (WM) lesions were identified, and their volumes measured. Brain gray matter and WM volumes were also calculated. Between-group comparisons were performed using χ(2), Mann-Whitney, and analysis of variance tests. Poisson regressions for count data were used to model the number of lesions of the 2 groups of patients.
Compared to adults, pediatric patients had shorter disease duration and lower disability. WM lesion number and volume did not differ between pediatric and adult patients with MS. CLs were detected in 2 (8%) pediatric and 10 (66%) adult patients. Median CL volume was lower in pediatric than adult patients with RRMS (p = 0.0003). Regression analysis showed that pediatric patients had a lower number of CLs than adults (p = 0.0003), after adjusting for age, gender, Expanded Disability Status Scale score, and disease duration.
CLs are rare in pediatric patients with MS. Since pediatric patients with MS have a clinical onset closer to the biological onset of the disease than adult patients with MS, our findings indicate that CL formation is likely not to be an initial event in this disease.
Neurology 03/2011; 76(10):910-3. · 8.31 Impact Factor
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ABSTRACT: Despite behavioural signs of flattened affect, patients affected by schizophrenia show enhanced sensitivity to negative stimuli. The current literature concerning neural circuitry for emotions supports dysregulations of cortico-limbic networks, but gives contrasting results. Adverse childhood experiences (ACEs) could persistently influence emotional regulation and neural correlates of response to emotional stimuli in healthy humans. This study evaluated the effect of ACEs and chronic undifferentiated schizophrenia on neural responses to emotional stimuli (negative facial expression).
Brain blood-oxygen-level-dependent functional magnetic resonance imaging neural responses to a face-matching paradigm, and regional grey matter (GM) volumes were studied at 3.0 T in the amygdala, hippocampus, anterior cingulated cortex (ACC) and prefrontal cortex (PFC). The severity of ACEs was assessed. Participants included 20 consecutively admitted in-patients affected by chronic undifferentiated schizophrenia, and 20 unrelated healthy volunteers from the general population.
Patients reported higher ACEs than controls. Worse ACEs proportionally led to decreasing responses in the amygdala and hippocampus, and to increasing responses in the PFC and ACC in all participants. Patients showed higher activations in the amygdala and hippocampus, and lower activations in the PFC and ACC. Higher ACEs were associated with higher GM volumes in the PFC and ACC, and schizophrenia was associated with GM reduction in all studied regions.
Structural and functional brain correlates of emotional reactivity are influenced by both current chronic undifferentiated schizophrenia and the severity of past ACEs.
Psychological Medicine 03/2011; 41(3):509-19. · 6.16 Impact Factor
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ABSTRACT: Neuro-axonal damage is a well known sequelae of MS pathogeneses. Consequently, our aim was to test whether the ∼20% of patients with MS exhibiting a clinically benign disease course also have minimal neural dysfunction as reflected by the global concentration of their MR imaging marker NAA.
Q(NAA) was obtained with nonlocalizing whole-head (1)H-MR spectroscopy in 43 patients with benign RRMS (30 women, 13 men; mean age, 44.7 ± 7.3 years of age) with 21.0 ± 4.4 years (range, 15-35 years) of disease duration from the first symptom and an EDSS score of 1.9 (range, 0-3). Q(NAA) was by divided by the brain volume (from MR imaging segmentation) to normalize it into WBNAA. All participants gave institutional review board-approved written informed consent, and the study was HIPAA compliant.
The patients' lesion load was 12.2 ± 7.7 cm(3). Their 8.3 ± 1.8 mmol/L WBNAA was 35% lower than that in controls (P < .001). Individual average loss rates (absolute loss compared with controls divided by disease duration) clustered around 0.22 ± 0.09 mmol/L/year (1.7%/year, assuming monotonic decline). This rate could be extrapolated from that already reported for patients with RRMS of much shorter disease duration. WBNAA did not correlate with lesion load or EDSS.
Normal WBNAA is not characteristic of benign MS and is not an early predictor of its course. These patients, therefore, probably benefit from successful compensation and sparing of eloquent regions. Because they may ultimately have a rapid decline once their brain plasticity is exhausted, they may benefit from treatment options offered to more affected patients.
American Journal of Neuroradiology 10/2010; 32(1):204-9. · 2.93 Impact Factor
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F Benedetti,
S Poletti,
D Radaelli,
A Bernasconi,
R Cavallaro, A Falini,
C Lorenzi,
A Pirovano,
S Dallaspezia,
C Locatelli,
G Scotti,
E Smeraldi
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ABSTRACT: At the crossroad of multiple pathways regulating trophism and metabolism, glycogen synthase kinase (GSK)3 is considered a key factor in influencing the susceptibility of neurons to harmful stimuli (neuronal resilience) and is a target for several psychiatric drugs that directly inhibit it or increase its inhibitory phosphorylation. Inhibition of GSK3 prevents apoptosis and could protect against the neuropathological processes associated with psychiatric disorders. A GSK3-beta promoter single-nucleotide polymorphism (rs334558) influences transcriptional strength, and the less active form was associated with less detrimental clinical features of mood disorders. Here we studied the effect of rs334558 on grey matter volumes (voxel-based morphometry) of 57 patients affected by chronic schizophrenia. Carriers of the less active C allele variant showed significantly higher brain volumes in an area encompassing posterior regions of right middle and superior temporal gyrus, within the boundaries of Brodmann area 21. The temporal lobe is the brain parenchymal region with the most consistently documented morphometric abnormalities in schizophrenia, and neuropathological processes in these regions develop soon at the beginning of the illness. These results support the interest for GSK3-beta as a factor affecting neuropathology in major behavioural disorders, such as schizophrenia, and thus as a possible target for treatment.
Genes Brain and Behavior 06/2010; 9(4):365-71. · 3.48 Impact Factor
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ABSTRACT: This study explores default-mode network (DMN) abnormalities in patients with secondary progressive (SP) and primary progressive (PP) multiple sclerosis (MS) and whether such abnormalities correlate with cognitive impairment and damage to selected white matter (WM) fiber bundles, quantified using diffusion tensor (DT) MRI tractography.
Resting state (RS) functional MRI and DT MRI data were acquired from 33 patients with SPMS, 24 patients with PPMS, and 24 controls. Independent component analysis (ICA) was used to identify the DMN. SPM5 was used to assess within- and between-group activations.
Between-group differences in DMN activity were found in the left medial prefrontal cortex (mPFC), left precentral gyrus (PcG), and anterior cingulate cortex (ACC). Compared to controls, patients with SPMS had reduced activity in the mPFC (p = 0.01) and PcG (p = 0.02), while patients with PPMS had reduced activity in the PcG (p = 0.008) and the ACC (p = 0.002). Compared to patients with PPMS, patients with SPMS had increased ACC activity (p = 0.04). Reduction of RS activity in the ACC was more pronounced in cognitively impaired vs cognitively preserved patients with MS (p = 0.02). In patients with MS, DMN abnormalities correlated with the PASAT and word list test scores (r values ranging from 0.35 to 0.45) and DT MRI changes in the corpus callosum and the cingulum (r values ranging from 0.82 to 0.87).
These results suggest that a dysfunction of the anterior components of the default-mode network may be among the factors responsible for the accumulation of cognitive deficits in patients with progressive multiple sclerosis.
Neurology 04/2010; 74(16):1252-9. · 8.31 Impact Factor
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[hide abstract]
ABSTRACT: Wernicke's encephalopathy (WE) is an acute or subacute syndrome that results from a deficiency in vitamin B1 (thiamine). The syndrome is characterised by a classical triad of symptoms: nystagmus and ophthalmoplegia,mental-status changes, and unsteadiness of stance and gait. When patients with WE are inappropriately treated with low doses of thiamine, mortality rates average out at 20% and Korsakoff's Psychosis develops in about 85% of survivors(Sechi and Serra in Lancet Neurol 6(5):442–455,2007). We report the case of a patient with a pyloric substenosis that developed a WE, and was treated with high doses of thiamine showing after few days of treatment a great improvement of neurological and neuroradiological assessment, even though cognitive impairment was still severe at discharge and at 6 months follow-up.
Neurological Sciences 04/2010; 31(6):859-61. · 1.32 Impact Factor
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ABSTRACT: In patients with ALS, conventional MR imaging is frequently noninformative, and its use has been restricted to excluding other conditions that can mimic ALS. Conversely, the extensive application of modern MR imaging-based techniques to the study of ALS has undoubtedly improved our understanding of disease pathophysiology and is likely to have a role in the identification of potential biomarkers of disease progression. This review summarizes how new MR imaging technology is changing dramatically our understanding of the factors associated with ALS evolution and highlights the reasons why it should be used more extensively in studies of disease progression, including clinical trials.
American Journal of Neuroradiology 04/2010; 31(10):1769-77. · 2.93 Impact Factor
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ABSTRACT: Cognitive deficits affect <or=30% of patients with PPMS. We investigated the functional correlates of cognitive network dysfunction in patients with PPMS and their correlation with the extent of structural MR imaging damage.
From 16 right-handed patients with PPMS and 17 matched controls, structural and fMRIs (during the performance of the 2-back task) were acquired. Neuropsychological tests exploring memory, attention, and frontal lobe cognitive domains were administered. T2 LL, NBV, and CC areas were measured.
Six patients with PPMS were CI. Structural MR imaging measures did not differ between patients who were CI and those who were CP. Compared with patients who were CI, patients who were CP had increased activations of the left caudate nucleus, PFC, and inferior parietal lobule. Compared with controls and patients who were CP, patients who were CI had increased activations of the SII, cerebellum, and insula. Compared with controls, they also had increased activations of the right precentral gyrus and a reduced recruitment of the left PFC. In patients with PPMS, a decreased composite cognitive score correlated with increased activity of the cerebellum, insula, and SII, as well as decreased PFC activity. T2 LL correlated with decreased PFC recruitment and increased SII recruitment.
In PPMS, an increased recruitment of cognitive-related networks might represent a functional reserve with the potential to limit the severity of cognitive impairment. The accumulation of T2 lesions and the consequent exhaustion of frontal lobe plasticity might contribute to cognitive impairment in PPMS.
American Journal of Neuroradiology 03/2010; 31(7):1240-6. · 2.93 Impact Factor
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ABSTRACT: We investigated motor network function in patients with benign multiple sclerosis (BMS) and contrasted the results with those obtained from patients with secondary progressive multiple sclerosis (SPMS) and healthy controls (HC) to elucidate better the factors associated with a favorable clinical evolution in multiple sclerosis (MS).
Diffusion tensor (DT) and fMRI scans during the performance of a simple motor task were prospectively acquired from 17 patients with BMS, 15 patients with SPMS, and 17 HC. Patients with BMS and SPMS were matched for age, gender, and disease duration. DT MRI histograms of the normal-appearing white matter (NAWM) and gray matter (GM) were derived. fMRI analysis was performed using SPM5 (Wellcome Department of Cognitive Neurology, London, UK).
Compared with HC, patients with BMS and SPMS had increased activations of the left primary sensorimotor cortex. Patients with SPMS also showed increased activations of the left secondary sensorimotor cortex, left inferior frontal gyrus (IFG), right hippocampus, and several visual areas. Compared with HC and patients with BMS, patients with SPMS had reduced activations of the left supplementary motor area, left putamen, and right cerebellum. Compared with patients with BMS, patients with SPMS had increased activations of the left IFG and right middle occipital gyrus. In patients with MS, fMRI changes were correlated with T2 lesion volumes and DT MRI changes in the NAWM and GM.
This study shows that, contrary to what happens in secondary progressive multiple sclerosis, the movement-associated pattern of activations seen in benign multiple sclerosis resembles that of healthy people, and its abnormalities are restricted to the sensorimotor network. The long-term preservation of brain functional adaptive mechanisms in these patients is likely to contribute to their favorable clinical course.
Neurology 01/2010; 74(2):142-9. · 8.31 Impact Factor
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V Martinelli,
M A Rocca,
P Annovazzi,
A Pulizzi,
M Rodegher,
F Martinelli Boneschi,
R Scotti, A Falini,
M P Sormani,
G Comi,
M Filippi
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ABSTRACT: To compare the efficacy, tolerability, and safety of IV methylprednisolone (IV MP) vs oral methylprednisolone (oMP) at equivalent high doses in patients with multiple sclerosis (MS) experiencing a recent relapse.
Patients with a clinical relapse within the previous 2 weeks and at least 1 gadolinium (Gd)-enhancing lesion on a screening brain MRI scan were included. Forty patients with MS were randomized to receive either 1 g/day for 5 days of oMP (20 patients) or 1 g/day for 5 days of IV MP (20 patients). Expanded Disability Status Scale (EDSS) and brain MRI (dual-echo and postcontrast T1-weighted scans) were assessed at baseline and at weeks 1 and 4. The study primary research question (endpoint) was to compare the efficacy of the 2 treatment routes in reducing the number of Gd-enhancing lesions after 1 week from treatment initiation. Secondary outcomes were safety, tolerability, and clinical efficacy profiles of the 2 routes of administration.
The 2 groups showed a reduction of Gd-enhancing lesions over time (p = 0.002 for oMP and p = 0.001 for IV MP) with a "non-inferiority effect" between the 2 routes of administration at week 1. Both groups showed an improvement of EDSS over time (p < 0.001) without between-group difference at week 4. Both treatments were well-tolerated and adverse events were minimal and occurred similarly in the 2 treatment arms.
Oral methylprednisolone (oMP) is as effective as IV methylprednisolone in reducing gadolinium-enhancing lesions in patients with MS soon after an acute relapse with similar clinical, safety, and tolerability profiles. This study provides class III evidence that 1 g oMP x 5 days is not inferior to 1 g IV MP x 5 days in reducing the number of gadolinium-enhancing lesions over a period of 1 week (mean difference in lesion reduction comparing IV MP to oMP is -20%, 95% confidence interval -48% to + 5%).
Neurology 12/2009; 73(22):1842-8. · 8.31 Impact Factor
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ABSTRACT: Using diffusion tensor (DT) tractography, we quantified optic radiation (OR) structural changes in seven migraine patients with (MA) and eight without visual aura (MoA) and their relation to clinical manifestations and T2-visible burden. The corticospinal tract and the corpus callosum were studied as 'control' white matter (WM). No difference was found for any of the WM fibre bundles metrics between controls and MoA patients. MA patients had reduced average fractional anisotropy (FA) of both OR compared with controls and reduced average FA of the right OR compared with MoA patients. They also showed higher right OR mean diffusivity than controls. OR metrics were not correlated with clinical and magnetic resonance imaging (MRI) metrics. DT tractography reveals OR changes in MA patients that might represent a phenotypic biomarker of the disease given the lack of correlation with clinical and structural MRI metrics.
Cephalalgia 10/2008; 28(10):1061-8. · 3.43 Impact Factor
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ABSTRACT: Corticobasal degeneration (CBD) presents with symptoms that often overlap with other neurological conditions. In many cases, diagnosis, prognosis and consequent clinical management remain uncertain. Structural and functional asymmetric brain changes represent the most consistent imaging findings that may assist in CBD diagnosis. Diffusion Tensor MRI (DT-MRI) is a quantitative technique that allows microscopic tissue abnormalities to be non-invasively assessed in vivo. A single case of clinically suspected CBD with symmetric diffuse brain atrophy on conventional-MRI scans was studied using DT-MRI by voxel-wise comparison with eight healthy subjects. The lateralized distribution of DT-MRI abnormalities was consistent with clinical features providing a substantial support to the diagnosis.
Parkinsonism & Related Disorders 08/2008; 14(5):436-9. · 3.80 Impact Factor
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ABSTRACT: The mirror neuron system (MNS) is an observation-execution matching system activated, in humans, during action observation, motor learning, and imitation of action. We used functional MRI (fMRI) to investigate the properties of the MNS in patients with multiple sclerosis (MS).
Using a 3 tesla scanner, we acquired fMRI in 16 right-handed patients with relapsing-remitting MS and 14 controls. Two motor tasks were studied. The first consisted of repetitive flexion-extension of the last four fingers of the right hand (simple task) alternated to epochs of rest; the second (MNS task) consisted of observation of a movie showing the hand of another subject while performing the same task.
During the simple task, compared to controls, patients with MS had more significant activations of the contralateral primary sensorimotor cortex and supplementary motor area. During the MNS task, both groups showed the activation of several visual areas, the infraparietal sulcus, and the inferior frontal gyrus (IFG), bilaterally. The IFG and the visual areas were significantly more active in patients than controls. The between-group interaction analysis showed that in patients with MS, part of the regions of the MNS were more active also during the simple task.
This study suggests increased activation of the mirror neuron system in patients with multiple sclerosis (MS) with a normal level of function and widespread CNS damage. The potentialities of this system in facilitating clinical recovery in patients with MS and other neurologic conditions should be investigated.
Neurology 02/2008; 70(4):255-62. · 8.31 Impact Factor
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ABSTRACT: Gene polymorphisms in the mammalian biological clock system influence individual rhythms. A single nucleotide polymorphism (SNP) in the 3' flanking region of CLOCK (3111 T/C; rs1801260) influenced diurnal preference in healthy humans and caused sleep phase delay and insomnia in patients affected by bipolar disorder. Genes of the biological clock are expressed in many brain structures other than in the 'master clock' suprachiasmatic nuclei. These areas, such as cingulate cortex, are involved in the control of many human behaviors. Clock genes could then bias 'nonclock' functions such as information processing and decision making. Thirty inpatients affected by a major depressive episode underwent blood oxygen-level dependent (BOLD) functional magnetic resonance imaging (fMRI). The cognitive activation paradigm was based on a go/no-go task. Morally connoted words were presented. Genotyping of CLOCK was performed for each patients. We measured activity levels through actimetry during the day before the fMRI study. CLOCK 3111 T/C SNP was associated with activity levels in the second part of the day, neuropsychological performance and BOLD fMRI correlates (interaction of genotype and moral valence of the stimuli). Our results support the hypothesis that individual clock genotype may influence several variables linked with human behaviors in normal and psychopathological conditions.
Genes Brain and Behavior 02/2008; 7(1):20-5. · 3.48 Impact Factor
