Different types of abstract concepts: evidence from two neurodegenerative patients.

The observation of neurological patients showing selective impairments for specific conceptual categories contributed in the development of semantic memory theories. Here, we studied two patients (P01, P02), affected, respectively, by the semantic variant of Primary Progressive Aphasia (sv-PPA) and Cortico-Basal Syndrome (CBS). An implicit lexical decision task, including concrete (animals, tools) and abstract (emotions, social, quantity) concepts, was administered to patients and healthy controls.P01 and P02 showed an abolished priming effect for social and quantity-related concepts, respectively. This double dissociation suggests a role of different brain areas in representing specific abstract categories, giving insights for current semantic memory theories.

Italian consensus recommendations for a biomarker-based aetiological diagnosis in mild cognitive impairment patients.

BACKGROUND AND PURPOSE: Biomarkers support the aetiological diagnosis of neurocognitive disorders in vivo. Incomplete evidence is available to drive clinical decisions; available diagnostic algorithms are generic and not very helpful in clinical practice. The aim was to develop a biomarker-based diagnostic algorithm for mild cognitive impairment patients, leveraging on knowledge from recognized national experts. METHODS: With a Delphi procedure, experienced clinicians making variable use of biomarkers in clinical practice and representing five Italian scientific societies (neurology - Società Italiana di Neurologia per le Demenze; neuroradiology - Associazione Italiana di Neuroradiologia; biochemistry - Società Italiana di Biochimica Clinica; psychogeriatrics - Associazione Italiana di Psicogeriatria; nuclear medicine - Associazione Italiana di Medicina Nucleare) defined the theoretical framework, relevant literature, the diagnostic issues to be addressed and the diagnostic algorithm. An N-1 majority defined consensus achievement. RESULTS: The panellists chose the 2011 National Institute on Aging and Alzheimer's Association diagnostic criteria as the reference theoretical framework and defined the algorithm in seven Delphi rounds. The algorithm includes baseline clinical and cognitive assessment, blood examination, and magnetic resonance imaging with exclusionary and inclusionary roles; dopamine transporter single-photon emission computed tomography (if no/unclear parkinsonism) or metaiodobenzylguanidine cardiac scintigraphy for suspected dementia with Lewy bodies with clear parkinsonism (round VII, votes (yes-no-abstained): 3-1-1); 18 F-fluorodeoxyglucose positron emission tomography for suspected frontotemporal lobar degeneration and low diagnostic confidence of Alzheimer's disease (round VII, 4-0-1); cerebrospinal fluid for suspected Alzheimer's disease (round IV, 4-1-0); and amyloid positron emission tomography if cerebrospinal fluid was not possible/accepted (round V, 4-1-0) or inconclusive (round VI, 5-0-0). CONCLUSIONS: These consensus recommendations can guide clinicians in the biomarker-based aetiological diagnosis of mild cognitive impairment, whilst guidelines cannot be defined with evidence-to-decision procedures due to incomplete evidence.

An updated Italian normative dataset for the Stroop color word test (SCWT).

The Stroop color and word test (SCWT) is widely used to evaluate attention, information processing speed, selective attention, and cognitive flexibility. Normative values for the Italian population are available only for selected age groups, or for the short version of the test. The aim of this study was to provide updated normal values for the full version, balancing groups across gender, age decades, and education. Two kinds of indexes were derived from the performance of 192 normal subjects, divided by decade (from 20 to 90) and level of education (4 levels: 3-5; 6-8; 9-13; >13 years). They were (i) the correct answers achieved for each table in the first 30 s (word items, WI; color items, CI; color word items, CWI) and (ii) the total time required for reading the three tables (word time, WT; color time, CT; color word time, CWT). For each index, the regression model was evaluated using age, education, and gender as independent variables. The normative data were then computed following the equivalent scores method. In the regression model, age and education significantly influenced the performance in each of the 6 indexes, whereas gender had no significant effect. This study confirms the effect of age and education on the main indexes of the Stroop test and provides updated normative data for an Italian healthy population, well balanced across age, education, and gender. It will be useful to Italian researchers studying attentional functions in health and disease.

A normative study of the Italian printed word version of the free and cued selective reminding test.

According to the new research criteria for the diagnosis of Alzheimer's disease, episodic memory impairment, not significantly improved by cueing, is the core neuropsychological marker, even at a pre-dementia stage. The FCSRT assesses verbal learning and memory using semantic cues and is widely used in Europe. Standardization values for the Italian population are available for the colored picture version, but not for the 16-item printed word version. In this study, we present age- and education-adjusted normative data for FCSRT-16 obtained using linear regression techniques and generalized linear model, and critical values for classifying sub-test performance into equivalent scores. Six scores were derived from the performance of 194 normal subjects (MMSE score, range 27-30, mean 29.5 ± 0.5) divided per decade (from 20 to 90), per gender and per level of education (4 levels: 3-5, 6-8, 9-13, >13 years): immediate free recall (IFR), immediate total recall (ITR), recognition phase (RP), delayed free recall (DFR), delayed total recall (DTR), Index of Sensitivity of Cueing (ISC), number of intrusions. This study confirms the effect of age and education, but not of gender on immediate and delayed free and cued recall. The Italian version of the FCSRT-16 can be useful for both clinical and research purposes.

Italian Frontotemporal Dementia Network (FTD Group-SINDEM): sharing clinical and diagnostic procedures in Frontotemporal Dementia in Italy.

In the prospect of improved disease management and future clinical trials in Frontotemporal Dementia, it is desirable to share common diagnostic procedures. To this aim, the Italian FTD Network, under the aegis of the Italian Neurological Society for Dementia, has been established. Currently, 85 Italian Centers involved in dementia care are part of the network. Each Center completed a questionnaire on the local clinical procedures, focused on (1) clinical assessment, (2) use of neuroimaging and genetics; (3) support for patients and caregivers; (4) an opinion about the prevalence of FTD. The analyses of the results documented a comprehensive clinical and instrumental approach to FTD patients and their caregivers in Italy, with about 1,000 newly diagnosed cases per year and 2,500 patients currently followed by the participating Centers. In analogy to other European FTD consortia, future aims will be devoted to collect data on epidemiology of FTD and its subtypes and to provide harmonization of procedures among Centers.

Babesia bovis: lipids from virulent S2P and attenuated R1A strains trigger differential signalling and inflammatory responses in bovine macrophages.

The intra-erythrocytic protozoan Babesia bovis is an economically important pathogen that causes an acute and often fatal infection in adult cattle. Babesiosis limitation depends on the early activation of macrophages, essential cells of the host innate immunity, which can generate an inflammatory response mediated by cytokines and nitric oxide (NO). Herein, we demonstrate in bovine macrophages that lipids from B. bovis attenuated R1A strain (LA) produced a stronger NO release, an early TNFα mRNA induction and 2-fold higher IL-12p35 mRNA levels compared to the lipids of virulent S2P strain (LV). Neither LA nor LV induced anti-inflammatory IL-10. Regarding signalling pathways, we here report that LA induced a significant phosphorylation of p38 and extracellular signal-regulated kinases 1 and 2 (ERK1/2) whereas LV only induced a reduced activation of ERK1/2. Besides, NF-κB was activated by LA and LV, but LA produced an early degradation of the inhibitor IκB. Interestingly, LV and the majority of its lipid fractions, exerted a significant inhibition of concanavalin A-induced peripheral blood mononuclear cell proliferation with respect to LA and its corresponding lipid fractions. In addition, we determined that animals infected with R1A developed a higher increase in IgM anti-phosphatidylcholine than those inoculated with S2P. Collectively, S2P lipids generated a decreased inflammatory response contributing to the evasion of innate immunity. Moreover, since R1A lipids induced a pro-inflammatory profile, we propose these molecules as good candidates for immunoprophylactic strategies against babesiosis.

White matter damage in frontotemporal lobar degeneration spectrum.

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.

Education and occupation provide reserve in both ApoE ε4 carrier and noncarrier patients with probable Alzheimer's disease.

According to the reserve hypothesis, a high educational/occupational attainment can modulate Alzheimer's disease (AD) clinical expression. The impact of the Apolipoprotein E (ApoE) ε4 allele on the reserve mechanism in AD has not been assessed. Aim of this European multicenter study was to evaluate the metabolic correlates of reserve and ApoE genotype in early probable AD. 51 AD subjects, 27 ε4 carriers, and 24 noncarriers, underwent FDG-PET brain imaging. We used the general linear model as implemented in SPM2 to test for the linear correlation of a reserve index, accounting for both educational and occupational level, with brain glucose metabolism, controlling for demographic variables (age and gender) and for cognitive performance. We found an inverse correlation between a reserve index, accounting for educational/occupational level, and metabolism in the posterior cingulate cortex and precuneus in both ε4 carriers and noncarriers, and no significant difference between the groups. We show that education and occupation act as proxies for reserve in ε4 carriers, compensating for an unfavorable genetic background; we also show that the degree of compensation does not differ significantly by ApoE ε4 status.

Free and Cued Selective Reminding Test: an Italian normative study.

The presence of episodic memory impairment is required for the diagnosis of Alzheimer's dementia by all current diagnostic criteria. The new research criteria proposed by Dubois et al. (Lancet Neurol 6:734-746, 2007) require that the impairment should not improve significantly with cueing, recognition testing nor after the control of effective encoding. This is considered to be the core deficit of "prodromal Alzheimer's disease". The Free and Cued Selective Reminding Test (FCSRT) is a memory test that allows in assessing these specific features of memory impairment. Here, we report normative data for an Italian version of the FCSRT. The test is based on the 12 pictorial stimuli, 6 belonging to the living domain, and 6 to the non-living domain. Six scores were derived from the performance of 227 healthy Italian adults, with age, sex and education homogenously distributed across subgroups: immediate free recall (IFR), immediate total recall (ITR), delayed-free recall (DFR), delayed total recall (DTR), Index of Sensitivity of Cueing (ISC), number of intrusions. In multiple regression analyses, age emerged as an influencing factor for both IFR and DFR, with older people obtaining lower scores. Education and gender appear to influence only IFR, with better performance by more educated subjects and females. Adjusted scores were used to determine inferential cutoff scores and to compute equivalent scores.

The multidimensionality of abstract concepts: A systematic review.

The neuroscientific study of conceptual representation has largely focused on categories of concrete entities (biological entities, tools…), while abstract knowledge has been less extensively investigated. The possible presence of a categorical organization of abstract knowledge is a debated issue. An embodied cognition framework predicts an organization of the abstract domain into different dimensions, grounded in the brain regions engaged by the corresponding experience. Here we review the types of experience that have been proposed to characterize different categories of abstract concepts, and the evidence supporting a corresponding organization derived from behavioural, neuroimaging (i.e., fMRI, MRI, PET, SPECT), EEG, and neurostimulation (i.e., TMS) studies in healthy and clinical populations. The available data provide substantial converging evidence in favour of the presence of distinct neural representations of social and emotional knowledge, mental states and magnitude concepts, engaging brain systems involved in the corresponding experiences. This evidence is supporting an extension of embodied models of semantic memory organization to several types of abstract knowledge.

Generalization of the effects of phonological training for anomia using structural equation modelling: a multiple single-case study.

Structural Equation Modelling analysis of three longitudinal er-fMRI sessions was used to test the impact of phonological training and of the generalization process on the pattern of brain connectivity during overt picture naming in two chronic anomic patients. Phonological training yielded a positive effect on the trained material. Six months after the training, a generalization of the positive impact on the untrained items was also observed. Connectivity analysis showed that training and generalization effects shared paralleled cortical patterns of functional integration. These findings may represent the neurophysiological correlate of the training-induced cognitive strategies for the compensation of anomia.

The neural bases of word encoding and retrieval: A fMRI-guided transcranial magnetic stimulation study.

There is evidence that the human prefrontal cortex is asymmetrically involved in long-term episodic memory processing. Moreover, abstract and concrete words processing has been reported to differentially involve prefrontal and parietal areas. We implemented a two-stages functional magnetic resonance imaging (fMRI)-repetitive transcranial magnetic stimulation (rTMS) paradigm to investigate the role of the dorsolateral prefrontal cortices (DLPFCs) and parietal cortices (PARCs) in encoding and retrieval of abstract and concrete words. Using this paradigm we could select areas to be stimulated on the basis of single-subject (SS) anatomical and functional data, investigating the usefulness of this integration approach. With respect to fMRI, abstract and concrete words differed only for a greater left fusiform gyrus activation for concrete words. In turn, significant rTMS effects were found, but only for the retrieval of abstract words. Consistent with previous findings, repetitive stimulation of the right DLPFC had a specific impact on episodic retrieval. Memory retrieval performance was also disrupted when rTMS was applied to the left PARC. Finally, we found a significant positive correlation between the effect sizes of SS right PARC activations for abstract word retrieval and the consequent rTMS interference effects. Taken together these data provide for the first time evidence that also the PARC has a necessary role in episodic retrieval of abstract words. Importantly, from a methodological perspective, our data demonstrate that fMRI-guided rTMS with a SS approach provides a powerful tool to investigate the neural underpinnings of cognitive functions.

Gender-related differences in moral judgments.

The moral sense is among the most complex aspects of the human mind. Despite substantial evidence confirming gender-related neurobiological and behavioral differences, and psychological research suggesting gender specificities in moral development, whether these differences arise from cultural effects or are innate remains unclear. In this study, we investigated the role of gender, education (general education and health education) and religious belief (Catholic and non-Catholic) on moral choices by testing 50 men and 50 women with a moral judgment task. Whereas we found no differences between the two genders in utilitarian responses to non-moral dilemmas and to impersonal moral dilemmas, men gave significantly more utilitarian answers to personal moral (PM) dilemmas (i.e., those courses of action whose endorsement involves highly emotional decisions). Cultural factors such as education and religion had no effect on performance in the moral judgment task. These findings suggest that the cognitive-emotional processes involved in evaluating PM dilemmas differ in men and in women, possibly reflecting differences in the underlying neural mechanisms. Gender-related determinants of moral behavior may partly explain gender differences in real-life involving power management, economic decision-making, leadership and possibly also aggressive and criminal behaviors.

Early diagnosis of Alzheimer's disease: the role of biomarkers including advanced EEG signal analysis. Report from the IFCN-sponsored panel of experts.

Alzheimer's disease (AD) is the most common neurodegenerative disease among the elderly with a progressive decline in cognitive function significantly affecting quality of life. Both the prevalence and emotional and financial burdens of AD on patients, their families, and society are predicted to grow significantly in the near future, due to a prolongation of the lifespan. Several lines of evidence suggest that modifications of risk-enhancing life styles and initiation of pharmacological and non-pharmacological treatments in the early stage of disease, although not able to modify its course, helps to maintain personal autonomy in daily activities and significantly reduces the total costs of disease management. Moreover, many clinical trials with potentially disease-modifying drugs are devoted to prodromal stages of AD. Thus, the identification of markers of conversion from prodromal form to clinically AD may be crucial for developing strategies of early interventions. The current available markers, including volumetric magnetic resonance imaging (MRI), positron emission tomography (PET), and cerebral spinal fluid (CSF) analysis are expensive, poorly available in community health facilities, and relatively invasive. Taking into account its low cost, widespread availability and non-invasiveness, electroencephalography (EEG) would represent a candidate for tracking the prodromal phases of cognitive decline in routine clinical settings eventually in combination with other markers. In this scenario, the present paper provides an overview of epidemiology, genetic risk factors, neuropsychological, fluid and neuroimaging biomarkers in AD and describes the potential role of EEG in AD investigation, trying in particular to point out whether advanced analysis of EEG rhythms exploring brain function has sufficient specificity/sensitivity/accuracy for the early diagnosis of AD.

Dyslexia: cultural diversity and biological unity.

The recognition of dyslexia as a neurodevelopmental disorder has been hampered by the belief that it is not a specific diagnostic entity because it has variable and culture-specific manifestations. In line with this belief, we found that Italian dyslexics, using a shallow orthography which facilitates reading, performed better on reading tasks than did English and French dyslexics. However, all dyslexics were equally impaired relative to their controls on reading and phonological tasks. Positron emission tomography scans during explicit and implicit reading showed the same reduced activity in a region of the left hemisphere in dyslexics from all three countries, with the maximum peak in the middle temporal gyrus and additional peaks in the inferior and superior temporal gyri and middle occipital gyrus. We conclude that there is a universal neurocognitive basis for dyslexia and that differences in reading performance among dyslexics of different countries are due to different orthographies.

The NOS3 G894T (Glu298Asp) polymorphism is a risk factor for frontotemporal lobar degeneration.

BACKGROUND AND AIMS: Neuronal nitric oxide synthase (NOS)1 C276T polymorphism was shown to increase the risk for frontotemporal lobar degeneration (FTLD). In the brain, both NOS1 and NOS3 (endothelial isoform) have been detected. The distribution of NOS3 G894T (Glu298Asp) and T-786C single nucleotide polymorphisms (SNPs) was analyzed in a population of 222 patients with FTLD compared with 218 age-matched controls to determine whether they could influence the susceptibility to develop the disease. RESULTS: A statistically significant increased frequency of the NOS3 G894T SNP was observed in patients as compared with controls (40.0 vs. 31.4%, P = 0.011, OR: 1.65, CI: 1.13-2.42). Conversely, the distribution of the T-786C SNP was similar in patients and controls. No differences were observed stratifying according to gender. DISCUSSION: The NOS3 G894T polymorphism likely acts as risk factor for sporadic FTLD, but studies in larger populations are needed to confirm these preliminary findings.

DCUN1D1 is a risk factor for frontotemporal lobar degeneration.

BACKGROUND AND PURPOSE: Frontotemporal lobar degeneration (FTLD) is considered as a proteinopathy; therefore, it is conceivable that genes encoding for factors involved in protein misfolding and/or degradation could play a role in its pathogenesis. METHODS: An association study of defective in cullin neddylation 1 (DCN-1)-domain containing 1 (DCUN1D1), which is involved in protein degradation, was carried out in a population of 220 patients with FTLD as compared with 229 age-matched controls. RESULTS: A statistically significant increased frequency of the GG genotype of the DCUN1D1 rs4859146 single nucleotide polymorphism (SNP) was observed in patients compared with controls (6.9 vs. 1.7%, P = 0.011, adjusted OR: 4.39, 95% CI: 1.40-13.78). Stratifying according to the clinical syndrome, significant differences were observed between the behavioral variant of frontotemporal dementia and controls (GG frequency: 6.3 vs. 1.7%, P = 0.02, OR:4.0, 95%, CI = 1.24-12.92), as well as between patients with progressive aphasia compared with controls (15.4 vs. 1.7%, P = 0.014, OR = 11.30, 95%, CI = 1.63-78.45), but not in patients with SD versus controls (8.3 vs. 1.7%, P = 0.18, OR = 5.24, 95% C.I. = 0.45-60.63). No significant differences in allelic and genotypic frequencies of the DCUN1D1 rs4859147 SNP were found. CONCLUSIONS: The GG genotype of the DCUN1D1 rs4859147 SNP represents a risk factor for the development of FTLD, increasing the risk of about fourfold.

Reduction of parasite levels in blood improves pregnancy outcome during experimental Trypanosoma cruzi infection.

Infection with a myotropic Trypanosoma cruzi clone induces maternal fertility failure. In the current work, we evaluated whether reduction of maternal parasitaemia before mating has beneficial effects on pregnancy outcome. Female mice were subjected to benznidazole (Bz) treatment after infection. On day 30 of therapy, mating was assessed and pregnancy outcome was determined on day 14 of gestation. Fetal resorptions diminished in T. cruzi-infected Bz-treated mice compared with T. cruzi-infected untreated mice. This was in agreement with the reduction in the blood/solid tissue parasite load and with the percentage of necrotic foci in placental samples from T. cruzi-infected Bz-treated females. To study eventual changes in the immune homeostasis of T. cruzi-infected Bz-treated mice, activation of the immune system was evaluated at the end of Bz therapy and before mating. We found specific IgG1 reduction resulting in a predominance of specific IgG2a, reduced numbers of CD69+ CD4+ cells and diminished frequency and numbers of CD44+ T cells. Concanavalin A-stimulated splenocytes from T. cruzi-infected Bz-treated mice produced higher amounts of IFN-gamma than T. cruzi-infected untreated mice. These results indicate that reduction of maternal parasite load improves pregnancy outcome. These findings correlate with a favourable modulation of the immune response.

Transcranial magnetic stimulation improves naming in Alzheimer disease patients at different stages of cognitive decline.

OBJECTIVE: Word-finding difficulty (anomia) is commonly observed in Alzheimer's dementia (AD). The aim of this study was to assess the effect of repetitive transcranial magnetic stimulation (rTMS) applied to the dorso-lateral prefrontal cortex (dlPFC) on picture naming in 24 probable AD patients with different degrees of cognitive decline. METHODS: High-frequency rTMS was applied to the left and right dlPFC during object and action naming in AD patients. A sham stimulation was used as a control condition. RESULTS: Whilst, as previously reported, stimulation to both the left and the right dlPFC improved action, but not object naming in the mild AD group; an improved naming accuracy for both classes of stimuli was found in the moderate to severe group. CONCLUSIONS: Repetitive transcranial magnetic stimulation applied to the dlPFC improves naming performance also in the advanced stages of AD. Moreover, in the severe group the effect is not specific for action naming, as in the case of the mild AD group. These findings suggest that rTMS can affect the intrinsic ability of the brain to restore or compensate for damaged function and may represent an useful new tool for cognitive rehabilitation.

Neuronal nitric oxide synthase C276T polymorphism increases the risk for frontotemporal lobar degeneration.

The neuronal nitric oxide synthase (nNOS) is abundantly expressed in the brain and its transcripts have been found in the frontal cerebral cortex. Eighty-nine patients with different neurodegenerative tau-related disorders, including 71 patients with frontotemporal lobar degeneration (FTLD), 12 with progressive supranuclear palsy (PSP) and 6 with corticobasal degeneration (CBD), were genotyped for the C276T single nucleotide polymorphism (SNP) in exon 29 of the nNOS gene and compared with 190 age-matched controls (CON). A significantly increased allelic frequency of the T allele was observed in patients compared with CON (40.4% vs. 29.7%, P = 0.014, OR: 1.94, CI: 1.15-3.27). Considering each disorder separately, significance was reached for FTLD only (39.4%, P = 0.0248 versus controls, OR: 1.96, CI: 1.11-3.47). However, the frequency of the T allele was elevated also in patients with PSP (45.8%) and CBD (41.7%). No differences were observed stratifying according to gender or apolipoprotein E status. The C276T SNP acts as risk factor for sporadic FTLD, possibly influencing NOS1 transcription. Studies in larger populations are needed to confirm its role in PSP and CBD.