Publications by authors named "Carmelina Chiriaco"

30 Publications

  • Page 1 of 1

One Hour-Post-load Plasma Glucose ≥155 mg/dl in Healthy Glucose Normotolerant Subjects Is Associated With Subcortical Brain MRI Alterations and Impaired Cognition: A Pilot Study.

Front Aging Neurosci 2021 4;13:608736. Epub 2021 Feb 4.

Geriatrics Division, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy.

Glucose alterations are associated with impaired cognition. The 1-h-post-load plasma glucose ≥155 mg/dl in non-diabetic subjects confers an increased risk of cardiovascular events and diabetes. This pilot study aimed to investigate whether the 1-h-post-load plasma glucose ≥155 mg/dl negatively affects the subcortical regions of the brain and the cognitive functions. We enrolled 32 non-diabetic subjects. Patients were divided into two groups based on 1-h- post-load plasma glucose value > or < 155 mg/dl: normal glucose tolerance (NGT) 1-h-high and NGT 1-h-low subjects. All subjects underwent 3 Tesla MRI and standard neuropsychological tests. NGT 1-h-high subjects showed significantly lower values of both right (4.9 ± 0.9 vs. 5.1 ± 0.9 ml) and left (4.8 ± 1.1 vs. 5.1 ± 1.1 ml) hippocampal hemisphere volume, while right hemisphere hippocampal diffusivity was lower in the NGT 1-h-high group (10.0 ± 0.6 vs. 10.6 ± 0.5 10 mms). NGT 1-h-high subjects also showed a poorer memory performance. In particular, for both Rey Auditory Verbal Learning Task (RAVLT)-immediate-recall and Free and Cued Selective Reminding Test (FCSRT)-delayed total recall, we found lower cognitive test scores in the NGT-1 h-high group (26.5 ± 6.3 and 10.4 ± 0.3, respectively). One-hour-post-load hyperglycemia is associated with morpho-functional subcortical brain alterations and poor memory performance tests.
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http://dx.doi.org/10.3389/fnagi.2021.608736DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7891177PMC
February 2021

Neuropsychological assessment could distinguish among different clinical phenotypes of progressive supranuclear palsy: A Machine Learning approach.

J Neuropsychol 2021 Sep 24;15(3):301-318. Epub 2020 Nov 24.

Neuroscience Research Center, Magna Graecia University, Catanzaro, Italy.

Progressive supranuclear palsy (PSP) is a rare, rapidly progressive neurodegenerative disease. Richardson's syndrome (PSP-RS) and predominant parkinsonism (PSP-P) are characterized by wide range of cognitive and behavioural disturbances, but these variants show similar cognitive pattern of alterations, leading difficult differential diagnosis. For this reason, we explored with an Artificial Intelligence approach, whether cognitive impairment could differentiate the phenotypes. Forty Parkinson's disease (PD) patients, 25 PSP-P, 40 PSP-RS, and 34 controls were enrolled following the consensus criteria diagnosis. Participants were evaluated with neuropsychological battery for cognitive domains. Random Forest models were used for exploring the discriminant power of the cognitive tests in distinguishing among the four groups. The classifiers for distinguishing diseases from controls reached high accuracies (86% for PD, 95% for PSP-P, 99% for PSP-RS). Regarding the differential diagnosis, PD was discriminated from PSP-P with 91% (important variables: HAMA, MMSE, JLO, RAVLT_I, BDI-II) and from PSP-RS with 92% (important variables: COWAT, JLO, FAB). PSP-P was distinguished from PSP-RS with 84% (important variables: JLO, WCFST, RAVLT_I, Digit span_F). This study revealed that PSP-P, PSP-RS and PD had peculiar cognitive deficits compared with healthy subjects, from which they were discriminated with optimal accuracies. Moreover, high accuracies were reached also in differential diagnosis. Most importantly, Machine Learning resulted to be useful to the clinical neuropsychologist in choosing the most appropriate neuropsychological tests for the cognitive evaluation of PSP patients.
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http://dx.doi.org/10.1111/jnp.12232DOI Listing
September 2021

Hippocampal impairment in patients with Essential Tremor.

Parkinsonism Relat Disord 2020 03 19;72:56-61. Epub 2020 Feb 19.

Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy; Neuroscience Centre, Magna Graecia University, Catanzaro, Italy. Electronic address:

Introduction: There is growing evidence that a proportion of patients with Essential Tremor (ET) may develop a memory impairment over time. However, no studies have evaluated whether hippocampal damage really occur in ET. This study investigated the macro and micro-structural integrity of the hippocampus in ET subjects using a multimodal MRI approach.

Methods: Neuropsychological and MRI data were acquired from 110 participants (60 patients with ET and 50 age-, sex-, and education-matched healthy controls [HC]). Whole-brain T1-weighted and Diffusion Tensor Imaging (DTI) were performed to assess macro-and microstructural alterations. MRI parameters (volume; mean diffusivity [MD]; fractional anisotropy [FA]) of bilateral hippocampi were obtained. In order to evaluate the relationship between MRI alterations and neurocognitive impairment, hippocampal parameters were also correlated with cognitive test scores.

Results: Compared to controls, ET patients showed a subclinical memory impairment with significantly lower memory scores, but within the normal ranges. Despite the subclinical damage, however, ET patients showed a significant increase in MD values in the bilateral hippocampi in comparison with HC. A significant correlation was also found between MD and memory scores in ET.

Conclusion: This study improves the knowledge on memory impairment in ET, as our results demonstrate for the first time the hippocampal microstructural damage related to subclinical memory impairment in ET patients. Further studies are needed before these findings can be considered predictive of a distinct ET subtype or suggestive of a co-occurent dementia.
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http://dx.doi.org/10.1016/j.parkreldis.2020.02.006DOI Listing
March 2020

The embodiment of language in tremor-dominant Parkinson's disease patients.

Brain Cogn 2019 10 18;135:103586. Epub 2019 Jul 18.

IBFM, National Research Council, 88100 Catanzaro, Italy; Neuroscience Centre, University "Magna Graecia" 88100, Catanzaro, Italy; Medical and Surgical Sciences Department, University "Magna Graecia", Catanzaro 88100, Italy.

According to embodied cognition, processing language with motor content involves a simulation of this content by the brain motor system. Patients with brain lesions involving the motor system are characterized by deficits in action verbs processing in the absence of dementia. We sought to assess whether action verbs interfere with the motor behavior of patients with Parkinson's disease (PD) having tremor dominant symptoms. PD tremor is considered to result from dysfunction of cortical-subcortical motor circuits driven by dopamine depletion. In addition, PD tremor is reduced during active movement execution. Therefore, likewise movement execution, the motor simulation of bodily actions predicted by the embodiment may show to be effective in modifying tremor by interfering with a dysfunctional motor system. Here, we asked to simply read and repeat words expressing a hand-related bodily action. Abstract verbs served as control. Changes in tremor kinematics were evaluated using a monoaxial accelerometer. Seventeen PD patients with rest tremor of the upper limbs were enrolled. Tremor amplitude was significantly smaller when reading action verbs as compared to abstract verbs. We provide empirical evidence supporting the embodied cognition theory by showing that circuits mediating tremor of PD patients are distinctively affected by processing action language.
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http://dx.doi.org/10.1016/j.bandc.2019.103586DOI Listing
October 2019

Functional activity changes in memory and emotional systems of healthy subjects with déjà vu.

Epilepsy Behav 2019 08 7;97:8-14. Epub 2019 Jun 7.

Department of Medical and Surgical Sciences, Institute of Neurology, University "Magna Graecia", Catanzaro, Italy; Neuroimaging Research Unit, Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy. Electronic address:

Déjà vu (DV) is a fascinating and mysterious human experience that has attracted interest from psychologists and neuroscientists for over a century. In recent years, several studies have been conducted to unravel the psychological and neurological correlates of this phenomenon. However, the neural mechanisms underlying the DV experience in benign manifestations are still poorly understood. Thirty-three healthy volunteers completed an extensive neuropsychiatric and neuropsychological battery including personality evaluation. The presence of DV was assessed with the Inventory for Deja vu Experiences Assessment. Participants underwent episodic memory learning test, and 2 days later during event-related functional magnetic resonance imaging (fMRI), they are asked to rate old and new pictures as a novel, moderately/very familiar, or recollected. We identified 18 subjects with DV (DV+) and 15 without DV (DV-) matched for demographical, neuropsychological, and personality characteristics. At a behavioral level, no significant difference was detected in the episodic memory tasks between DV+ and DV-. Functional magnetic resonance imaging analysis revealed that DV+, independently from task conditions, were characterized by increased activity of the bilateral insula coupled with reduced activation in the right parahippocampal, both hippocampi, superior/middle temporal gyri, thalami, caudate nuclei, and superior frontal gyri with respect to DV-. Our study demonstrates that individuals who experienced DV are not characterized by different performance underlying familiarity/recollection memory processes. However, fMRI results provide evidence that the physiological DV experience is associated with the employment of different neural responses of brain regions involved in memory and emotional processes.
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http://dx.doi.org/10.1016/j.yebeh.2019.05.018DOI Listing
August 2019

REM-Sleep Behavior Disorder in Patients With Essential Tremor: What Is Its Clinical Significance?

Front Neurol 2019 24;10:315. Epub 2019 Apr 24.

Neuroimaging Research Unit, Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy.

REM sleep behavior disorder (RBD) is an important risk factor for the dementia development and for the deterioration of autonomic functions in patients with Parkinson's Disease. RBD has also been reported in patients with Essential Tremor (ET). However, its clinical significance in ET remains still unknown. We aimed to investigate clinical, neuropsychological and cardiac autonomic scintigraphic differences between ET patients with and without RBD. To assess RBD symptoms, RBD Single-Question has been administered in a cohort of 55 patients with a clinical diagnosis of ET. Patients with clinical RBD underwent polysomnography (PSG) confirmation. All patients completed a battery of neuropsychological assessment of memory, executive function, attention, language, and visuospatial function. Cardiac MIBG scintigraphy was performed in order to measure the cardiac autonomic innervation. Ten ET patients (18%) had a PSG-confirmed RBD (ET). Compared to ET patients without RBD (ET), significantly reduced scores on memory domain tests such as Rey auditory verbal learning test immediate recall ( = 0.015) and Rey auditory verbal learning test delayed recall ( = 0.004) and phonemic fluency test ( = 0.028) were present in ET. By contrast, no other significant clinical difference has emerged from the comparison between two ET groups. Similarly, ET patients have cardiac MIBG tracer uptake in the normal value range as occurred in those with ET. This study improves the knowledge on clinical significance of RBD symptoms in ET patients. Our preliminary findings demonstrate that presence of RBD in ET is associated with neurocognitive impairment, but not with cardiac autonomic dysfunction. Further longitudinal studies are needed to investigate whether ET patients with RBD will develop a frank dementia over the time.
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http://dx.doi.org/10.3389/fneur.2019.00315DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6491751PMC
April 2019

In vivo evidence for decreased scyllo-inositol levels in the supplementary motor area of patients with Progressive Supranuclear Palsy: A proton MR spectroscopy study.

Parkinsonism Relat Disord 2019 05 11;62:185-191. Epub 2018 Dec 11.

Neuroimaging Research Unit, Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy; Neuroscience Research Centre, Magna Græcia University, Catanzaro, Italy. Electronic address:

Introduction: Several structural and functional neuroimaging studies have shown that the Supplementary Motor Area (SMA) is affected by tau pathology in patients with Progressive Supranuclear Palsy (PSP). The aim of the study was to investigate the biochemical profile of SMA in PSP patients, using proton magnetic resonance spectroscopy (H-MRS).

Methods: Sixteen PSP patients and 18 healthy controls participated in this study. H-MRS was performed by using a Point RESolving Spectroscopy (PRESS) single-voxel sequence implemented on a 3-T scanner. A voxel of 25 × 25 × 15 mm involving the right and left SMA was acquired in all subjects. Peak areas of N-acetyl-aspartate + N-acetyl-aspartyl-glutamate (NAA), creatine with phosphocreatine (Cr), glycerophosphocholine + phosphocholine (Cho), glutamate + glutamine (Glx), glutathione (GSH), myo-Inositol (mI) and Scyllo-Inositol (Scyllo) were calculated using a version 6.3-1K of the fitting program LCModel. Comparative analysis was performed on both absolute concentrations and ratio values relative to Cr.

Results: PSP patients showed a significant decrease in Scyllo concentration and Scyllo/Cr ratio values in SMA, compared to controls, whereas no difference between groups was found for the other ratio values. Of note, the attention and working memory functions were positively related to Scyllo and Scyllo/Cr values in PSP patients.

Conclusions: Our study demonstrates that Scyllo and Scyllo/Cr were significantly reduced in the SMA of PSP patients. Because Scyllo seems to be able to protect against formation of toxic fibrils of amyloid-beta fragments and tau oligomers deposition, these preliminary findings may open new perspectives to investigate Scyllo as a new potential disease-modifying therapy for PSP.
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http://dx.doi.org/10.1016/j.parkreldis.2018.12.008DOI Listing
May 2019

A new MR imaging index for differentiation of progressive supranuclear palsy-parkinsonism from Parkinson's disease.

Parkinsonism Relat Disord 2018 09 25;54:3-8. Epub 2018 Jul 25.

Neuroimaging Research Unit, Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy.

Introduction: Differentiating clinically progressive supranuclear palsy-parkinsonism (PSP-P) from Parkinson's disease (PD) may be challenging, especially in the absence of vertical supranuclear gaze palsy (VSGP). The Magnetic Resonance Parkinsonism Index (MRPI) has been reported to accurately distinguish between PSP and PD, yet few data exist on the usefulness of this biomarker for the differentiation of PSP-P from PD.

Methods: Thirty-four patients with PSP-P, 46 with PSP-Richardson's syndrome (PSP-RS), 53 with PD, and 53 controls were enrolled. New consensus criteria for the clinical diagnosis of PSP were used as the reference standard. The MRPI, and a new index termed MRPI 2.0 including the measurement of the third ventricle width (MRPI multiplied by third ventricle width/frontal horns width ratio), were calculated on T1-weighted MR images.

Results: The MRPI differentiated patients with PSP-P from those with PD with sensitivity and specificity of 73.5% and 98.1%, respectively, while the MRPI 2.0 showed higher sensitivity (100%) and similar specificity (94.3%) in differentiating between these two groups. Both biomarkers showed excellent performance in differentiating PSP-P patients with VSGP from those with PD, but the MRPI 2.0 was much more accurate (95.8%) than MRPI in differentiating PSP-P patients with slowness of vertical saccades from PD patients.

Conclusion: The MRPI 2.0 accurately differentiated PSP-P patients from those with PD. This new index was more powerful than MRPI in differentiating PSP patients in the early stage of the disease with slowness of vertical saccades from patients with PD, thus helping clinicians to consolidate the diagnosis based on clinical features, in vivo.
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http://dx.doi.org/10.1016/j.parkreldis.2018.07.016DOI Listing
September 2018

Multimodal assessment of normal-appearing corpus callosum is a useful marker of disability in relapsing-remitting multiple sclerosis: an MRI cluster analysis study.

J Neurol 2018 Oct 26;265(10):2243-2250. Epub 2018 Jul 26.

Institute of Molecular Bioimaging and Physiology, National Research Council (IBFM-CNR), Catanzaro, Italy.

Background And Purpose: Corpus callosum (CC) is frequently involved in relapsing-remitting multiple sclerosis (RRMS). Magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) allow to study CC macrostructural and microstructural tissue integrity. Here, we applied a data-driven approach to MRI and DTI data of normal-appearing CC in RRMS subjects, and subsequently evaluated if differences in tissue integrity corresponded to different levels of physical disability and cognitive impairment.

Methods: 74 RRMS patients and 20 healthy controls (HC) underwent 3 T MRI and DTI. Thickness and fractional anisotropy (FA) along midsagittal CC were extracted, and values from RRMS patients were fed to a hierarchical clustering algorithm. We then used ANOVA to test for differences in clinical and cognitive variables across the imaging-based clusters and HC.

Results: We found three distinct MRI-based subgroups of RRMS patients with increasing severity of CC damage. The first subgroup showed callosal integrity similar to HC (Cluster 1); Cluster 2 had milder callosal damage; a third subgroup showed the most severe callosal damage (Cluster 3). Cluster 3 included patients with longer disease duration and worst scores in Expanded Disability Status Scale. Cognitive domains of verbal memory, executive functions and processing speed were impaired in Cluster 3 and Cluster 2 compared to Cluster 1 and HC.

Conclusions: Within the same homogeneous cohort of patients, we could identify three neuroimaging RRMS clusters characterized by different involvement of normal-appearing CC. Interestingly, these corresponded to three distinct levels of clinical and cognitive disability.
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http://dx.doi.org/10.1007/s00415-018-8980-yDOI Listing
October 2018

Evaluation of machine learning algorithms performance for the prediction of early multiple sclerosis from resting-state FMRI connectivity data.

Brain Imaging Behav 2019 Aug;13(4):1103-1114

National Research Council, Institute of Bioimaging and Molecular Physiology (IBFM), Catanzaro, Italy.

Machine Learning application on clinical data in order to support diagnosis and prognostic evaluation arouses growing interest in scientific community. However, choice of right algorithm to use was fundamental to perform reliable and robust classification. Our study aimed to explore if different kinds of Machine Learning technique could be effective to support early diagnosis of Multiple Sclerosis and which of them presented best performance in distinguishing Multiple Sclerosis patients from control subjects. We selected following algorithms: Random Forest, Support Vector Machine, Naïve-Bayes, K-nearest-neighbor and Artificial Neural Network. We applied the Independent Component Analysis to resting-state functional-MRI sequence to identify brain networks. We found 15 networks, from which we extracted the mean signals used into classification. We performed feature selection tasks in all algorithms to obtain the most important variables. We showed that best discriminant network between controls and early Multiple Sclerosis, was the sensori-motor I, according to early manifestation of motor/sensorial deficits in Multiple Sclerosis. Moreover, in classification performance, Random Forest and Support Vector Machine showed same 5-fold cross-validation accuracies (85.7%) using only this network, resulting to be best approaches. We believe that these findings could represent encouraging step toward the translation to clinical diagnosis and prognosis.
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http://dx.doi.org/10.1007/s11682-018-9926-9DOI Listing
August 2019

Relationship between Hippocampal Subfields and Category Cued Recall in AD and PDD: A Multimodal MRI Study.

Neuroscience 2018 02 29;371:506-517. Epub 2017 Dec 29.

Neuroimaging Research Unit, Institute of Bioimaging and Molecular Physiology, National Research Council, Catanzaro, Italy; Institute of Neurology, Department of Medical Sciences, University "Magna Graecia", Catanzaro, Italy. Electronic address:

Alzheimer's disease (AD) and Parkinson's disease with dementia (PDD) are characterized by a different mnesic failure, particularly in memory cued recall. Although hippocampal involvement has been shown in both these diseases, it remains unknown whether a selective damage of specific subfields within the hippocampus may be responsible for the peculiar mnesic profile observed in AD and PDD. To explore this topic, we combined a multimodal 3 T-MRI hippocampal evaluation (whole-brain T1-weighted and diffusion tensor imaging) with a hippocampal-targeted neuropsychological assessment (Free and Cued Selective Reminding Test [FCSRT]) in 22 AD subjects, 18 PDD and 17 healthy controls. Macro- and microstructural features (volume; shape; mean diffusivity [MD]; fractional anisotropy [FA]) of bilateral hippocampi (whole and subfields) were obtained. Correlations between MRI-derived parameters and neuropsychological evaluations were performed. In the comparison between AD and PDD, the multimodal analysis allowed us to identify that subiculum, CA1 and CA4-DG were differently involved in these diseases and correlated with immediate and delayed total recall items of FCSRT. Moreover, compared to controls, AD showed a reduction in almost all subfields, with a MD increase in the same regions, whereas PDD displayed a volume loss, less severe than AD, more evident in the CA2-3 and presubiculum subfields. Our study provides new evidence that hippocampal subregions had different vulnerability to damage related to AD and PDD. The combination of the in vivo analysis of hippocampal subfields with the FCSRT paradigm provided important insights into whether changes within specific hippocampal subfields are related to the different mnesic profile in AD and PDD patients.
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http://dx.doi.org/10.1016/j.neuroscience.2017.12.028DOI Listing
February 2018

Color vision as a biological marker able to differentiate two phenotypically similar neurological diseases.

Neurol Sci 2018 05 14;39(5):951-952. Epub 2017 Dec 14.

National Researches Council, Research Section, Institute of Molecular Bioimaging and Physiology, 88100, Germaneto, Catanzaro, Italy.

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http://dx.doi.org/10.1007/s10072-017-3219-8DOI Listing
May 2018

Neuropsychological heterogeneity in patients with primary familial brain calcification due to a novel mutation in SLC20A2.

Neurol Sci 2018 02 21;39(2):379-380. Epub 2017 Sep 21.

Institute of Molecular Bioimaging and Physiology, National Research Council, (IBFM-CNR) Section of Germaneto, Catanzaro, Italy.

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http://dx.doi.org/10.1007/s10072-017-3125-0DOI Listing
February 2018

Processing graspable object images and their nouns is impaired in Parkinson's disease patients.

Cortex 2018 03 27;100:32-39. Epub 2017 Mar 27.

Dipartimento di Scienze Mediche e Chirurgiche, Magna Graecia University, Catanzaro, Italy; Consiglio Nazionale delle Ricerche, IBFM, Catanzaro, Italy.

According to embodiment, the recruitment of the motor system is necessary to process language material expressing a motor content. Coherently, an impairment of the motor system should affect the capacity to process language items with a motor content. The aim of the present study was to assess the capacity to process graspable objects and their nouns in Parkinson's disease (PD) patients and healthy controls. Participants saw photos and nouns depicting graspable and non-graspable objects. Scrambled images and pseudo-words served as control stimuli. At 150 msec after stimulus presentation, they had to respond when the stimulus referred to a real object, and refrain from responding when it was meaningless (go-no go paradigm). In the control group, participants gave slower motor responses for stimuli (both photos and nouns) related to graspable objects as compared to non-graspable ones. This in keeping with data obtained in a previous study with young healthy participants. In the PD group, motor responses were similar for both graspable and non-graspable items. Moreover, error number was significantly greater than in controls. These findings support the notion that when the motor circuits are lesioned, like in PD, patients do not show the typical modulation of motor responses and have troubles in processing graspable objects and their nouns.
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http://dx.doi.org/10.1016/j.cortex.2017.03.009DOI Listing
March 2018

MR parkinsonism index predicts vertical supranuclear gaze palsy in patients with PSP-parkinsonism.

Neurology 2016 Sep 24;87(12):1266-73. Epub 2016 Aug 24.

From the Institute of Neurology (A.Q., M.M., G.A., F.P.), Magna Graecia University, Catanzaro, Italy; Neuroimaging Research Unit, Institute of Molecular Bioimaging and Physiology (A.Q., B.V., S.N., G.N., M.S., F.N., R.N., C.C., M.C.), National Research Council, Catanzaro, Italy; Department of Medicine (Neuroscience) (D.R.W.), Monash University, Melbourne, Australia; Neurology Unit (P.P.), Annunziata Hospital, Cosenza, Italy; and Department of Neuroscience (D.B.), San Giovanni di Dio Hospital, Crotone, Italy.

Objective: To identify a biomarker for predicting the appearance of vertical supranuclear gaze palsy (VSGP) in patients affected by progressive supranuclear palsy-parkinsonism (PSP-P).

Methods: Twenty-four patients with PSP-P were enrolled in the current study. Patients were clinically followed up every 6 months until the appearance of VSGP or the end of the follow-up (4 years). Participants underwent MRI at baseline and at the end of follow-up. Magnetic resonance parkinsonism index (MRPI), an imaging measure useful for diagnosing PSP, was calculated.

Results: Twenty-one patients with PSP-P completed follow-up, and 3 patients dropped out. Eleven of 21 patients with PSP-P developed VSGP after a mean follow-up period of 28.5 months (range 6-48 months), while the remaining 10 patients with PSP-P did not develop VSGP during the 4-year follow-up period. At baseline, patients with PSP-P who later developed VSGP had MRPI values significantly higher than those of patients not developing VSGP without overlapping values between the 2 groups. MRPI showed a higher accuracy (100%) in predicting VSGP than vertical ocular slowness (accuracy 33.3%) or postural instability with or without vertical ocular slowness (accuracy 71.4% and 42.9%, respectively).

Conclusions: Our study demonstrates that MRPI accurately predicted, on an individual basis, the appearance of VSGP in patients with PSP-P, thus confirming clinical diagnosis in vivo.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5035983PMC
http://dx.doi.org/10.1212/WNL.0000000000003125DOI Listing
September 2016

Cerebellar involvement in essential tremor with and without resting tremor: A Diffusion Tensor Imaging study.

Parkinsonism Relat Disord 2016 06 30;27:61-6. Epub 2016 Mar 30.

Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy; Institute of Neurology, University "Magna Graecia", Catanzaro, Italy. Electronic address:

Objective: Essential Tremor with resting tremor (rET) is a debated and poorly understood clinical phenotype. Converging evidences show that neurodegeneration of the cerebellum underlies the pathophysiology of ET, but it is not known if cerebellar changes also occurs in patients with rET. The aim of our study was to evaluate cerebellar microstructure in patients with ET with- (rET) and without resting tremor (ETwr) in comparison to healthy controls by MR Diffusion Tensor Imaging (DTI).

Methods: We studied 67 patients with ET (rET: 29 and ETwr: 38) and 39 age-matched healthy controls (HC). DTI was performed to measure fractional anisotropy (FA) and mean diffusivity (MD) of white and grey matter (WM, GM) in the entire cerebellum and in right and left cerebellar hemispheres.

Results: MD was significantly higher in the cerebellar GM of ET total group (10.39 ± 0.87) in comparison with HC (9.90 ± 0.71) (p = 0.0027). Interestingly, MD was significantly different when ETwr (10.48 ± 0.77) were compared with HC (p = 0.0017), whereas a trend toward significance were found between rET (10.29 ± 0.99) and HC (p = 0.067). No differences among groups were found in MD of cerebellar WM and in FA values neither in the WM nor in the GM.

Conclusion: Our results demonstrate the presence of microstructural changes in the cerebellum of patients with ET. It is noteworthy that rET showed intermediate values compared to HC and ETwr, suggesting that rET shares part of the pathophysiological mechanisms of ETwr, but cerebellar involvement seems do not fully account for rET. In addition to the cerebellar loops, other networks may play a role in rET pathophysiology.
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http://dx.doi.org/10.1016/j.parkreldis.2016.03.022DOI Listing
June 2016

Individual differences in depression are associated with abnormal function of the limbic system in multiple sclerosis patients.

Mult Scler 2016 07 9;22(8):1094-105. Epub 2015 Oct 9.

Department of Medical and Surgical Sciences, University 'Magna Graecia', Catanzaro, Italy/Institute of Bioimaging and Molecular Physiology, National Research Council, Catanzaro, Italy.

Background: Depression is common in patients with multiple sclerosis (MS), although the brain mechanisms of this psychiatric condition in MS are poorly understood. Specifically, it remains to be determined whether depression in MS is related to altered activity and functional connectivity patterns within limbic circuits.

Methods: Seventy-seven MS patients with variable levels of depression (as assessed via the Beck Depression Inventory) underwent functional magnetic resonance imaging while performing an emotional processing task. To conduct the functional connectivity analyses, the bilateral amygdala and hippocampus, two areas critically involved in the pathophysiology of depression, were chosen as 'seed' regions. Multiple regression models were used to assess how depression in MS patients was correlated with the activity and functional connectivity patterns within the limbic system.

Results: Depression scores in MS patients were negatively correlated: (1) with the activity in the subgenual cingulate cortex; (2) with the functional connectivity between the hippocampus and orbitofrontal cortex as well as the dorsolateral prefrontal cortex, and (3) with the functional connectivity between the amygdala and dorsolateral prefrontal cortex.

Conclusions: Our study showed that individual differences in depression in MS patients were significantly associated with altered regional activity and functional connectivity patterns within the limbic system.
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http://dx.doi.org/10.1177/1352458515606987DOI Listing
July 2016

The relationship between regional microstructural abnormalities of the corpus callosum and physical and cognitive disability in relapsing-remitting multiple sclerosis.

Neuroimage Clin 2015 18;7:28-33. Epub 2014 Nov 18.

Neuroimaging Unit, Institute of Molecular Bioimaging and Physiology, National Research Council (IBFM-CNR), Viale Europa, Germaneto, Catanzaro 88100, Italy ; Institute of Neurology, University "Magna Graecia", Germaneto, Catanzaro 88100, Italy.

Significant corpus callosum (CC) involvement has been found in relapsing-remitting multiple sclerosis (RRMS), even if conventional magnetic resonance imaging measures have shown poor correlation with clinical disability measures. In this work, we tested the potential of multimodal imaging of the entire CC to explain physical and cognitive disability in 47 patients with RRMS. Values of thickness, fractional anisotropy (FA) and mean diffusivity (MD) were extracted from 50 regions of interest (ROIs) sampled along the bundle. The relationships between clinical, neuropsychological and imaging variables were assessed by using Spearman's correlation. Multiple linear regression analysis was employed in order to identify the relative importance of imaging metrics in modeling different clinical variables. Regional fiber composition of the CC differentially explained the response variables (Expanded Disability Status Scale [EDSS], cognitive impairment). Increases in EDSS were explained by reductions in CC thickness and MD. Cognitive impairment was mainly explained by FA reductions in the genu and splenium. Regional CC imaging properties differentially explained disability within RRMS patients revealing strong, distinct patterns of correlation with clinical and cognitive status of patients affected by this specific clinical phenotype.
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http://dx.doi.org/10.1016/j.nicl.2014.11.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4299954PMC
September 2015

Cortical volume and folding abnormalities in Parkinson's disease patients with pathological gambling.

Parkinsonism Relat Disord 2014 Nov 9;20(11):1209-14. Epub 2014 Sep 9.

Neuroimaging Research Unit, IBFM-CNR, Germaneto, CZ, Italy; Institute of Neurology, University "Magna Graecia", Germaneto, CZ, Italy. Electronic address:

Purpose: Pathological gambling (PG) is one of the most devastating non-motor complications of Parkinson's disease (PD). Neuroanatomical abnormalities in PD patients with PG are poorly understood.

Methods: In the current study we investigated PD patients with and without PG using Voxel Based Morphometry (VBM) and local Gyrification Index (lGI), two neuroimaging techniques useful for detecting complementary morphological metrics in the brain. Twelve PD patients with PG were compared to 12 clinically-matched PD patients without PG and 24 healthy controls.

Results: PD patients with PG showed grey matter volume loss specifically in the orbitofrontal cortex (OFC) when compared to patients without PG, with the atrophy of this region correlating with the increase of gambling symptoms (G-SAS). Surface-based analysis complemented this evidence revealing that the OFC in the PD patients with PG was also characterized by a reduced lGI. Moreover, when compared to controls, PD patients with PG showed a more widespread anatomical neurodegeneration involving several limbic regions such as: the OFC, cingulate cortex, inferior frontal cortex and insular cortex. Otherwise, demographically-/clinically-matched PD patients without PG did not display significant anatomical changes.

Discussion: Our study demonstrates that combined grey matter atrophy and reduced lGI in the OFC differentiates PD patients with PG from those without PG, suggesting that this cortical area may play a critical role in the development of this drug-induced behavioral disorder.
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http://dx.doi.org/10.1016/j.parkreldis.2014.09.001DOI Listing
November 2014

Effect of aging on magnetic resonance measures differentiating progressive supranuclear palsy from Parkinson's disease.

Mov Disord 2014 Apr 26;29(4):488-95. Epub 2014 Feb 26.

Institute of Neurology, University "Magna Graecia", Germaneto, Catanzaro, Italy.

Imaging measurements, such as the ratio of the midsagittal areas of the midbrain and pons (midbrain/pons) and the Magnetic Resonance Parkinsonism Index (MRPI), have been proposed to differentiate progressive supranuclear palsy (PSP) from Parkinson's disease (PD). However, abnormal midbrain/pons values suggestive of PSP have also been reported in elderly individuals and in patients with PD. We investigated the effect of aging on single or combined imaging measurements of the brainstem. We calculated the midbrain/pons and the MRPI (the ratio of the midsagittal areas of the pons and the midbrain multiplied by the ratio of the middle cerebellar peduncle and superior cerebellar peduncle widths) in 152 patients affected by PD, 25 patients with PSP, and a group of 81 age-matched and sex-matched healthy controls using a 3-Tesla magnetic resonance imaging scanner. In healthy controls, aging was negatively correlated with midsagittal area of the midbrain and midbrain/pons values. In patients with PD, in addition to the effect of aging, the disease status further influenced the midbrain/pons values (R(2)  = 0.23; P < 0.001). In both groups, MRPI values were not influenced either by aging or by disease status. No effect of aging on either midbrain/pons or MRPI values was shown in the patients with PSP. Our findings indicated that the MRPI was not significantly influenced by aging or disease-related changes occurring in PD; whereas, in contrast, the midbrain/pons was influenced. Therefore, the MRPI appears to be a more reliable imaging measurement compared with midbrain/pons values for differentiating PSP from PD and controls in an elderly population.
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http://dx.doi.org/10.1002/mds.25821DOI Listing
April 2014

Neurofunctional correlates of attention rehabilitation in Parkinson's disease: an explorative study.

Neurol Sci 2014 Aug 20;35(8):1173-80. Epub 2014 Feb 20.

Istituto di Bioimmagini e Fisiologia Molecolare, Consiglio Nazionale delle Ricerche, Unità di Ricerca Neuroimmagini, Germaneto (CZ), 88100, Catanzaro, Italy,

The effectiveness of cognitive rehabilitation (CR) in Parkinson's disease (PD) is in its relative infancy, and nowadays there is insufficient information to support evidence-based clinical protocols. This study is aimed at testing a validated therapeutic strategy characterized by intensive computer-based attention-training program tailored to attention deficits. We further investigated the presence of synaptic plasticity by means of functional magnetic resonance imaging (fMRI). Using a randomized controlled study, we enrolled eight PD patients who underwent a CR program (Experimental group) and seven clinically/demographically-matched PD patients who underwent a placebo intervention (Control group). Brain activity was assessed using an 8-min resting state (RS) fMRI acquisition. Independent component analysis and statistical parametric mapping were used to assess the effect of CR on brain function. Significant effects were detected both at a phenotypic and at an intermediate phenotypic level. After CR, the Experimental group, in comparison with the Control group, showed a specific enhanced performance in cognitive performance as assessed by the SDMT and digit span forward. RS fMRI analysis for all networks revealed two significant groups (Experimental vs Control) × time (T0 vs T1) interaction effects on the analysis of the attention (superior parietal cortex) and central executive neural networks (dorsolateral prefrontal cortex). We demonstrated that intensive CR tailored for the impaired abilities impacts neural plasticity and improves some aspects of cognitive deficits of PD patients. The reported neurophysiological and behavioural effects corroborate the benefits of our therapeutic approach, which might have a reliable application in clinical management of cognitive deficits.
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http://dx.doi.org/10.1007/s10072-014-1666-zDOI Listing
August 2014

Diffusion tensor MRI changes in gray structures of the frontal-subcortical circuits in amyotrophic lateral sclerosis.

Neurol Sci 2014 Jun 17;35(6):911-8. Epub 2014 Jan 17.

Institute of Neurology, University Magna Græcia, Catanzaro, Italy.

In this study, we used an automated segmentation of regions of interest and co-registration to diffusion tensor imaging (DTI) images to investigate whether microstructural abnormalities occur in gray structures of the frontal-subcortical circuits in patients with amyotrophic lateral sclerosis (ALS). Twenty-four patients with probable or definite sporadic ALS and 22 healthy controls were enrolled in the study. Thirteen out of 24 ALS patients and all of the control subjects underwent a detailed neuropsychological evaluation. DTI was performed to measure mean diffusivity (MD) and fractional anisotropy in the frontal cortex, caudate, putamen, globus pallidus, thalamus, amygdala and hippocampus. MD values of ALS patients were significantly higher in the frontal cortex (P = 0.023), caudate (P = 0.01), thalamus (P = 0.019), amygdala (P = 0.012) and hippocampus (P = 0.002) compared to controls. MD of these structures significantly correlated to a variable degree with neurological disability and neuropsychological dysfunctions. The increased MD values in several cortical and subcortical gray structures and their correlations with neuropsychological variables substantiate a multisystemic degeneration in ALS and suggest that dysfunctions of frontal-subcortical circuits could play a pivotal role in frontal impairment and behavioral symptoms in ALS patients.
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http://dx.doi.org/10.1007/s10072-013-1626-zDOI Listing
June 2014

Dopamine-transporter levels drive striatal responses to apomorphine in Parkinson's disease.

Brain Behav 2013 May 22;3(3):249-62. Epub 2013 Mar 22.

Istituto di Scienze Neurologiche (ISN), Consiglio Nazionale delle Ricerche 88100, Catanzaro, Italia ; Dipartimento di Scienze Mediche e Chirurgiche, Università degli Studi "Magna Graecia" 88100, Catanzaro, Italia.

Dopaminergic therapy in Parkinson's disease (PD) can improve some cognitive functions while worsening others. These opposite effects might reflect different levels of residual dopamine in distinct parts of the striatum, although the underlying mechanisms remain poorly understood. We used functional magnetic resonance imaging (fMRI) to address how apomorphine, a potent dopamine agonist, influences brain activity associated with working memory in PD patients with variable levels of nigrostriatal degeneration, as assessed via dopamine-transporter (DAT) scan. Twelve PD patients underwent two fMRI sessions (Off-, On-apomorphine) and one DAT-scan session. Twelve sex-, age-, and education-matched healthy controls underwent one fMRI session. The core fMRI analyses explored: (1) the main effect of group; (2) the main effect of treatment; and (3) linear and nonlinear interactions between treatment and DAT levels. Relative to controls, PD-Off patients showed greater activations within posterior attentional regions (e.g., precuneus). PD-On versus PD-Off patients displayed reduced left superior frontal gyrus activation and enhanced striatal activation during working-memory task. The relation between DAT levels and striatal responses to apomorphine followed an inverted-U-shaped model (i.e., the apomorphine effect on striatal activity in PD patients with intermediate DAT levels was opposite to that observed in PD patients with higher and lower DAT levels). Previous research in PD demonstrated that the nigrostriatal degeneration (tracked via DAT scan) is associated with inverted-U-shaped rearrangements of postsynaptic D2-receptors sensitivity. Hence, it can be hypothesized that individual differences in DAT levels drove striatal responses to apomorphine via D2-receptor-mediated mechanisms.
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http://dx.doi.org/10.1002/brb3.115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3683285PMC
May 2013

MR imaging and cognitive correlates of relapsing-remitting multiple sclerosis patients with cerebellar symptoms.

J Neurol 2013 May 28;260(5):1358-66. Epub 2012 Dec 28.

Neuroimaging Research Unit, Institute of Neurological Sciences, National Research Council, 88100, Germaneto, CZ, Italy.

Multiple sclerosis (MS) is a demyelinating disease affecting the central nervous system, frequently associated with cognitive impairments. Damages of the cerebellum are very common features of patients with MS, although the impact of this clinical factor is generally neglected. Recent evidence from our group demonstrated that MS patients with cerebellar damages are characterized by selective cognitive dysfunctions related to attention and language abilities. Here, we aimed at investigating the presence of neuroanatomical abnormalities in relapsing-remitting MS patients with (RR-MSc) and without (RR-MSnc) cerebellar signs. Twelve RR-MSc patients, 14 demographically, clinically, and radiologically, matched RR-MSnc patients and 20 controls were investigated. All patients underwent neuropsychological assessment. After refilling of FLAIR lesions on the 3D T1-weighted images, VBM was performed using SPM8 and DARTEL. A correlation analysis was performed between VBM results and neuropsychological variables characterizing RR-MSc patients. Despite a similar clinical status, RR-MSc patients were characterized by more severe cognitive damages in attention and language domains with respect to RR-MSnc and controls. With respect to controls, RR-MSnc patients were characterized by a specific atrophy of the bilateral thalami that became more widespread (including motor cortex) in the RR-MSc group (FWE < 0.05). However, consistent with their well-defined neuropsychological deficits, RR-MSc group showed atrophies in the prefrontal and temporal cortical areas when directly compared with RR-MSnc group. Our results demonstrated that RR-MS patients having cerebellar signs were characterized by a distinct neuroanatomical profile, mainly involving cortical regions underpinning executive functions and verbal fluency.
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http://dx.doi.org/10.1007/s00415-012-6805-yDOI Listing
May 2013

Brain iron deposition in essential tremor: a quantitative 3-Tesla magnetic resonance imaging study.

Mov Disord 2013 Feb 12;28(2):196-200. Epub 2012 Dec 12.

Neuroimaging Research Unit, National Research Council, Catanzaro, Italy.

Studies have demonstrated brain iron deposition in neurodegenerative disease and in normal aging. Data on this topic are lacking in essential tremor (ET). The aim of our study was to investigate brain iron content in patients with ET, using quantitative magnetic resonance imaging (MRI) T2*-relaxometry. We enrolled 24 patients with ET and 25 age-matched healthy controls. Subjects were examined using a 3T MRI scanner. The protocol included conventional MRI sequences and quantitative T2*-relaxometry. Whole-brain voxel-based analyses showed significant differences in T2* values in bilateral globus pallidus, substantia nigra, and in right dentate nucleus (P < .001 uncorrected). In the bilateral pallidum, differences survived family-wise-error (FWE) correction for multiple comparisons (P < .05). The present study provides the first evidence of increased brain iron accumulation in ET patients. Our results are suggestive of a possible involvement of motor systems outside of the cerebellum/cerebellar pathway and, more specifically, of the globus pallidus.
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http://dx.doi.org/10.1002/mds.25263DOI Listing
February 2013

Computer-assisted cognitive rehabilitation of attention deficits for multiple sclerosis: a randomized trial with fMRI correlates.

Neurorehabil Neural Repair 2013 May 27;27(4):284-95. Epub 2012 Nov 27.

Unità di Ricerca Neuroimmagini, ISN-CNR, Catanzaro, Italy.

Background: Although a growing body of evidence has highlighted the role of cognitive rehabilitation (CR) in the management of cognitive dysfunctions in multiple sclerosis (MS), there is still no evidence for a validated therapeutic approach.

Objective: We propose a new therapeutic strategy characterized by a computer-based intensive attention training program in MS patients with predominant attention deficits. We aim to investigate the effectiveness of our rehabilitation procedure, tailored for those with impaired abilities, using functional magnetic resonance imaging (fMRI).

Methods: Using a double-blind randomized controlled study, we enrolled 12 MS patients, who underwent a CR program (experimental group), and 11 age-gender-matched MS patients, who underwent a placebo intervention (control group). fMRI was recorded during the execution of a cognitive task broadly used for assessing attention abilities in MS patients (paced visual serial addition test).

Results: Significant effects were detected both at a phenotypic and at an intermediate phenotypic level. After CR, the experimental group, in comparison with the control group, showed a specific enhanced performance in attention abilities as assessed by the Stroop task with an effect size of 0.88, which was associated with increased activity in the posterior cerebellar lobule and in the superior parietal lobule.

Conclusions: Our study demonstrates that intensive CR tailored for those with impaired abilities affects neural plasticity and improves some aspects of cognitive deficits in MS patients. The reported neurophysiological and behavioral effects corroborate the benefits of our therapeutic approach, which might have a reliable application in the clinical management of cognitive deficits in MS.
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http://dx.doi.org/10.1177/1545968312465194DOI Listing
May 2013

Cerebellar-parietal dysfunctions in multiple sclerosis patients with cerebellar signs.

Exp Neurol 2012 Oct 7;237(2):418-26. Epub 2012 Aug 7.

Unità di Ricerca Neuroimmagini, Istituto di Scienze Neurologiche-Consiglio Nazionale delle Ricerche, 88100 Catanzaro, Italy.

Consistent findings have shown that the cerebellum is critically implicated in a broad range of cognitive processes including executive functions. Of note, cerebellar symptoms and a number of cognitive deficits have been widely reported in patients with multiple sclerosis (MS). This study investigated for the first time the role of cerebellar symptoms in modulating the neural networks associated with a cognitive task broadly used in MS patients (Paced Visual Serial Addition Test (PVSAT)). Twelve relapsing-remitting (RR) MS patients with prevalent cerebellar signs and symptoms (RR-MSc), 15 RR-MS patients without cerebellar manifestation (RR-MSnc) and 16 matched-healthy controls were examined during functional magnetic resonance imaging (fMRI). We tested whether the RR-MSc patients displayed abnormal activations within "cognitive" cerebellar regions and other areas typically engaged in working memory and tightly connected with the cerebellum. Despite similar behavioral performances during fMRI, RR-MSc patients displayed, relatively to both RR-MSnc patients and controls, significantly greater responses in the left cerebellar Crus I/Lobule VI. RR-MSc patients also displayed reduced functional connectivity between the left cerebellar Crus I and the right superior parietal lobule (FWE<.05). These results demonstrated that the presence of the cerebellar signs drastically impacts on the neurofunctional networks underlying working memory in MS. The altered communication between the cerebellum and a cortical area implicated in short-term buffering and storage of relevant information, offer new insights into the pathophysiological mechanisms of cognition in MS.
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http://dx.doi.org/10.1016/j.expneurol.2012.07.020DOI Listing
October 2012

Altered cortical-cerebellar circuits during verbal working memory in essential tremor.

Brain 2011 Aug 11;134(Pt 8):2274-86. Epub 2011 Jul 11.

National Research Council, Neuroimaging Research Unit, Catanzaro, Italy.

Essential tremor is a common neurological disorder characterized by motor and cognitive symptoms including working memory deficits. Epidemiological research has shown that patients with essential tremor are at a higher risk to develop dementia relative to age-matched individuals; this demonstrates that cognitive impairments reflect specific, although poorly understood, disease mechanisms. Neurodegeneration of the cerebellum has been implicated in the pathophysiology of essential tremor itself; however, whether cerebellar dysfunctions relate to cognitive abnormalities is unclear. We addressed this issue using functional neuroimaging in 15 patients with essential tremor compared to 15 sex-, education- and age-matched healthy controls while executing a verbal working memory task. To remove confounding effects, patients with integrity of the nigrostriatal terminals, no dementia and abstinent from medications altering cognition were enrolled. We tested whether patients displayed abnormal activations of the cerebellum (posterior lobules) and other areas typically engaged in working memory (dorsolateral prefrontal cortex, parietal lobules). Between-groups differences in the interactions of these regions were also assessed with functional connectivity methods. Finally, we determined whether individual differences in neuropsychological and clinical measures modulated the magnitude of regional brain responses and functional connectivity data in patients with essential tremor. Despite similar behavioural performances, patients showed greater cerebellar response (crus I/lobule VI) compared to controls during attentional-demanding working memory trials (F = 8.8; P < 0.05, corrected). They also displayed altered functional connectivity between crus I/lobule VI and regions implicated in focusing attention (executive control circuit including dorsolateral prefrontal cortex, inferior parietal lobule, thalamus) and in generating distracting self-related thoughts (default mode network including precuneus, ventromedial prefrontal cortex and hippocampus) (T-values > 3.2; P < 0.05, corrected). These findings were modulated by the variability in neuropsychological measures: patients with low cognitive scores displayed reduced connectivity between crus I/lobule VI and the dorsolateral prefrontal cortex and enhanced connectivity between crus I/lobule VI and the precuneus (T-values > 3.7; P < 0.05, corrected). It is likely that cerebellar neurodegeneration underlying essential tremor is reflected in abnormal communications between key regions responsible for working memory and that adaptive mechanisms (enhanced response of crus I/lobule VI) occur to limit the expression of cognitive symptoms. The connectivity imbalance between the executive control circuit and the default mode network in patients with essential tremor with low cognitive scores may represent a dysfunction, driven by the cerebellum, in suppressing task irrelevant thoughts via focused attention. Overall, our results offer new insights into pathophysiological mechanisms of cognition in essential tremor and suggest a primary role of the cerebellum in mediating abnormal interactions between the executive control circuit and the default mode network.
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http://dx.doi.org/10.1093/brain/awr164DOI Listing
August 2011

Myocardial (123)I-MIBG scintigraphy for differentiation of Lewy bodies disease from FTD.

Neurobiol Aging 2010 Nov 9;31(11):1903-11. Epub 2009 Jan 9.

Institute of Neurology, University Magna Graecia, Catanzaro, Italy.

Clinical distinction between Lewy bodies disease (LBD) and frontotemporal dementia (FTD) is sometimes difficult. Nigrostriatal dopaminergic degeneration occurs in both LBD and FTD, limiting helpfulness of DAT imaging to differentiate these forms of dementia. Several studies have emphasized the usefulness of myocardial scintigraphy with (123)Metaiodobenzylguanidine ((123)I-MIGB) in assessing the sympathetic nerve terminals in LBD demonstrating that cardiac (123)I-MIGB uptake is decreased in patients with this disease. We investigated the role of cardiac (123)I-MIBG scintigraphy in differentiating patients with LBD from those with FTD. Clinical diagnosis of LBD and FTD was determined according to established consensus criteria. Nine patients with LBD (1 possible and 8 probable), 6 patients with FTD, and 16 control subjects were involved in the study. The heart to mediastinum ratio (H/M) of (123)I-MIBG uptake was markedly reduced in all patients with LBD (H/M early: 1.25±0.12; delayed: 1.14±0.13) whereas it was normal in patients with FTD (H/M early: 1.86±0.20; delayed: 1.80±0.23) and in controls (H/M early: 1.91±0.17; delayed: 1.99±0.19), suggesting that cardiac (123)I-MIBG scintigraphy can help distinguish patients with LBD from those with FTD.
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http://dx.doi.org/10.1016/j.neurobiolaging.2008.11.009DOI Listing
November 2010

Neuropsychological disturbances in frontal lobe epilepsy due to mutated nicotinic receptors.

Epilepsy Behav 2009 Feb 6;14(2):354-9. Epub 2008 Dec 6.

Department of Neurology, University Hospital and Medical School of Geneva, Geneva 14, Switzerland.

Mutations in nicotinic receptor subunits have been identified in some families with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE). Normal intelligence has currently been considered the rule, although anecdotal cases with intellectual disability have been reported. We aimed to evaluate the frequency and degree of neuropsychological disorders in ADNFLE associated with nicotinic receptor mutations by testing 11 subjects from four families with a comprehensive neuropsychological assessment. General intellectual function was below the normal range in 45% of the subjects. All were abnormal in one or more executive task. Memory was either more affected than executive functions or equally affected in two thirds of subjects, suggesting a frontotemporal pattern of cognitive impairment. Cognitive dysfunction appears to be an integral part of the broad phenotype of ADNFLE with nicotinic receptor mutations, a fact that has been underestimated until now. The cognitive disorder affects executive functions as well as memory in most subjects.
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http://dx.doi.org/10.1016/j.yebeh.2008.11.003DOI Listing
February 2009
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