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1.
Phys Rev Lett ; 131(16): 162501, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37925694

RESUMEN

Neutrinoless double beta decay (0νßß) is a yet unobserved nuclear process that would demonstrate Lepton number violation, a clear evidence of beyond standard model physics. The process two neutrino double beta decay (2νßß) is allowed by the standard model and has been measured in numerous experiments. In this Letter, we report a measurement of 2νßß decay half-life of ^{100}Mo to the ground state of ^{100}Ru of [7.07±0.02(stat)±0.11(syst)]×10^{18} yr by the CUPID-Mo experiment. With a relative precision of ±1.6% this is the most precise measurement to date of a 2νßß decay rate in ^{100}Mo. In addition, we constrain higher-order corrections to the spectral shape, which provides complementary nuclear structure information. We report a novel measurement of the shape factor ξ_{3,1}=0.45±0.03(stat)±0.05(syst) based on a constraint on the ratio of higher-order terms from theory, which can be reliably calculated. This is compared to theoretical predictions for different nuclear models. We also extract the first value for the effective axial vector coupling constant obtained from a spectral shape study of 2νßß decay.

2.
Brain Topogr ; 35(1): 121-141, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33768383

RESUMEN

We investigate both experimentally and using a computational model how the power of the electroencephalogram (EEG) recorded in human subjects tracks the presentation of sounds with acoustic intensities that increase exponentially (looming) or remain constant (flat). We focus on the link between this EEG tracking response, behavioral reaction times and the time scale of fluctuations in the resting state, which show considerable inter-subject variability. Looming sounds are shown to generally elicit a sustained power increase in the alpha and beta frequency bands. In contrast, flat sounds only elicit a transient upsurge at frequencies ranging from 7 to 45 Hz. Likewise, reaction times (RTs) in an audio-tactile task at different latencies from sound onset also present significant differences between sound types. RTs decrease with increasing looming intensities, i.e. as the sense of urgency increases, but remain constant with stationary flat intensities. We define the reaction time variation or "gain" during looming sound presentation, and show that higher RT gains are associated with stronger correlations between EEG power responses and sound intensity. Higher RT gain further entails higher relative power differences between loom and flat in the alpha and beta bands. The full-width-at-half-maximum of the autocorrelation function of the eyes-closed resting state EEG also increases with RT gain. The effects are topographically located over the central and frontal electrodes. A computational model reveals that the increase in stimulus-response correlation in subjects with slower resting state fluctuations is expected when EEG power fluctuations at each electrode and in a given band are viewed as simple coupled low-pass filtered noise processes jointly driven by the sound intensity. The model assumes that the strength of stimulus-power coupling is proportional to RT gain in different coupling scenarios, suggesting a mechanism by which slower resting state fluctuations enhance EEG response and shorten reaction times.


Asunto(s)
Electroencefalografía , Sonido , Estimulación Acústica , Humanos , Tiempo de Reacción
3.
Phys Rev Lett ; 126(18): 181802, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-34018798

RESUMEN

The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, the next-generation ton-scale bolometric 0νßß experiment. It consists of a 4.2 kg array of 20 enriched Li_{2}^{100}MoO_{4} scintillating bolometers to search for the lepton-number-violating process of 0νßß decay in ^{100}Mo. With more than one year of operation (^{100}Mo exposure of 1.17 kg×yr for physics data), no event in the region of interest and, hence, no evidence for 0νßß is observed. We report a new limit on the half-life of 0νßß decay in ^{100}Mo of T_{1/2}>1.5×10^{24} yr at 90% C.I. The limit corresponds to an effective Majorana neutrino mass ⟨m_{ßß}⟩<(0.31-0.54) eV, dependent on the nuclear matrix element in the light Majorana neutrino exchange interpretation.

4.
Eur J Neurol ; 25(11): 1333-1340, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29931723

RESUMEN

BACKGROUND AND PURPOSE: Cognitively stimulating life experiences and activities are deemed to moderate the clinical impact of brain damage progressively building a neural and cognitive reserve (CR). CR has been studied extensively in various neurodegenerative disorders, but not in corticobasal degeneration (CBD). METHODS: Using Statistical Parametric Mapping 8, years of education, as a determinant of CR, was correlated with tracer uptake on positron emission tomography with 18 F-fluorodeoxyglucose, as a marker of neurodegeneration, in 35 patients with various phenotypes of CBD, including a cognitive-motor composite score or symptoms duration as covariates for controlling disease stage. RESULTS: A cluster of relative hypometabolism was found associated with higher education in the left inferior regions of pre- and post-rolandic gyri and insula, which represent typical loci of neurodegeneration in CBD regardless of clinical presentation. CONCLUSIONS: The present findings extend to CBD the evidence gathered in other neurodegenerative disorders that a higher CR has a protective effect against the clinical manifestations of brain degeneration.


Asunto(s)
Enfermedades de los Ganglios Basales/diagnóstico por imagen , Reserva Cognitiva/fisiología , Degeneración Nerviosa/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Enfermedades de los Ganglios Basales/psicología , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Degeneración Nerviosa/psicología , Tomografía de Emisión de Positrones/métodos
5.
Neurol Sci ; 39(11): 1877-1879, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30084073

RESUMEN

INTRODUCTION: Orolingual angioedema (OA) is a known adverse effect of intravenous (i.v.) alteplase. We analyzed all patients treated with i.v. alteplase for stroke at our hospital since approval of i.v. thrombolysis in Italy in 2004 to assess the incidence of this complication. PATIENTS AND RESULTS: Four hundred thirty-three patients received alteplase for stroke from April 2004 to May 2017. Two women developed OA (0.4%; 95% confidence interval 0.1 to 1.6%). Angioedema was mild in one case and severe in the other, with massive swelling of the lips, tongue, and oropharyngeal mucosa, and oropharyngeal bleeding, requiring intubation. Neither patient used ACE-inhibitors. DISCUSSION: The incidence of orolingual angioedema was very low in our series. Although OA is usually mild, anaphylactoid reactions may rarely occur, because of the variable degree of activation of the complement system and kinin cascade caused by alteplase. In such instances, admission to neurointensive care may be required. Specific bradykinin antagonists or drugs that target the kallikrein-kinin system are beginning to be used in the more severe cases. Thus, doctors and nurses caring for acute stroke patients need to be able to recognize and treat this complication.


Asunto(s)
Angioedema/inducido químicamente , Angioedema/epidemiología , Fibrinolíticos/administración & dosificación , Accidente Cerebrovascular/terapia , Activador de Tejido Plasminógeno/administración & dosificación , Administración Intravenosa , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/epidemiología
6.
Nature ; 471(7339): 494-8, 2011 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-21430777

RESUMEN

The determination of rock friction at seismic slip rates (about 1 m s(-1)) is of paramount importance in earthquake mechanics, as fault friction controls the stress drop, the mechanical work and the frictional heat generated during slip. Given the difficulty in determining friction by seismological methods, elucidating constraints are derived from experimental studies. Here we review a large set of published and unpublished experiments (∼300) performed in rotary shear apparatus at slip rates of 0.1-2.6 m s(-1). The experiments indicate a significant decrease in friction (of up to one order of magnitude), which we term fault lubrication, both for cohesive (silicate-built, quartz-built and carbonate-built) rocks and non-cohesive rocks (clay-rich, anhydrite, gypsum and dolomite gouges) typical of crustal seismogenic sources. The available mechanical work and the associated temperature rise in the slipping zone trigger a number of physicochemical processes (gelification, decarbonation and dehydration reactions, melting and so on) whose products are responsible for fault lubrication. The similarity between (1) experimental and natural fault products and (2) mechanical work measures resulting from these laboratory experiments and seismological estimates suggests that it is reasonable to extrapolate experimental data to conditions typical of earthquake nucleation depths (7-15 km). It seems that faults are lubricated during earthquakes, irrespective of the fault rock composition and of the specific weakening mechanism involved.

7.
Vet Pathol ; 54(1): 147-154, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27337982

RESUMEN

Splenitis is uncommonly reported in dogs. Herein, the authors describe its prevalence, clinical findings and outcomes, histologic patterns, and causes. Splenic samples of dogs diagnosed with splenitis between 2005 and 2013 were collected and stained with hematoxylin and eosin, Gram, green-Gram, Giemsa, periodic acid-Schiff, and Ziehl-Neelsen. Samples were processed for polymerase chain reaction (PCR) to detect bacteria, fungi, and protozoa ( Leishmania infantum, Hepatozoon canis). Thirty-three of 660 splenic samples (5%) had splenitis. Clinical findings and outcomes were available in 19 dogs (58%); 49% had weakness, 33% had fever, and 84% survived. The most frequent inflammatory patterns included purulent splenitis (27%), pyogranulomatous splenitis (24%), and neutrophilic perisplenitis (15%). One dog had a putative diagnosis of primary splenitis; in 8 dogs, microorganisms were identified histologically or by PCR in the spleen without obvious comorbidities. Twenty-four dogs (73%) had concurrent diseases; a permissive role in the development of splenitis was suspected in 21 of these cases. Histologic examination identified the cause of splenitis in 10 dogs. Bacteria were identified by PCR in 23 cases, but the bacteria were confirmed histologically in only 6 of these. Leishmania was detected with PCR in 6 dogs. Leishmania was identified in 1 dog and H. canis in another histologically, but both were PCR negative. Fungi were identified in 8 spleens by PCR and in 1 by histology. This study suggests that splenitis is uncommon in dogs and is frequently associated with systemic diseases. Prognosis is favorable in most cases. Identification of bacteria, fungi, and protozoa in the spleens of affected dogs with PCR should be interpreted cautiously, because the findings are not confirmed histologically in many cases.


Asunto(s)
Enfermedades de los Perros/patología , Enfermedades del Bazo/veterinaria , Animales , Biopsia/veterinaria , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/etiología , Perros , Masculino , Reacción en Cadena de la Polimerasa/veterinaria , Bazo/microbiología , Bazo/parasitología , Bazo/patología , Enfermedades del Bazo/diagnóstico , Enfermedades del Bazo/etiología , Enfermedades del Bazo/patología
8.
Acta Psychiatr Scand ; 134(4): 339-49, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27273612

RESUMEN

OBJECTIVE: The objective of the study was to investigate the relationship between structural connectivity (SC) and functional connectivity (FC) in the cingulum in bipolar disorder (BD) and its various phases. METHOD: We combined resting-state functional magnetic resonance imaging and probabilistic tractographic diffusion tensor imaging to investigate FC and SC of the cingulum and its portions, the SC-FC relationship, and their correlations with clinical and neurocognitive measures on sustained attention in manic (n = 21), depressed (n = 20), and euthymic (n = 20) bipolar patients and healthy controls (HC) (n = 42). RESULTS: First, we found decreased FC between the anterior and posterior parts of the cingulum in manic patients when compared to depressed patients and HC. Second, we observed decreased SC of the cingulum bundle, particularly in its anterior part, in manic patients when compared to HC. Finally, alterations in the cingulum FC (but not SC) correlated with clinical severity scores while changes in the cingulum SC (but not FC) were related with neurocognitive deficits in sustained attention in BD. CONCLUSION: We demonstrate for the first time a reduction in FC and concomitantly in SC of the cingulum in mania, which correlated with psychopathological and neurocognitive parameters, respectively, in BD. This supports the central role of cingulum connectivity specifically in mania.


Asunto(s)
Trastorno Bipolar/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Imagen por Resonancia Magnética/métodos , Vías Nerviosas/fisiopatología , Trastorno Bipolar/fisiopatología , Mapeo Encefálico , Estudios Transversales , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Descanso
9.
Phys Rev Lett ; 110(8): 083901, 2013 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-23473147

RESUMEN

In this Letter we present experimental results concerning the retrieval of images of absorbing objects immersed in turbid media via differential ghost imaging (DGI) in a backscattering configuration. The method has been applied, for the first time to our knowledge, to the imaging of thin black objects located inside a turbid solution in proximity of its surface. We show that it recovers images with a contrast better than standard noncorrelated direct imaging, but equivalent to noncorrelated diffusive imaging. A simple theoretical model capable of describing the basic optics of DGI in turbid media is proposed.

10.
Int J Immunopathol Pharmacol ; 26(2): 299-304, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23755745

RESUMEN

Anxiety disorders (Ads) are the most common type of psychiatric disorders, Pharmacologic options studied for treating ADs may include benzodiazepines, tricyclic antidepressants (TCA), selective serotonin reuptake inhibitors (SSRIs), noradrenergic and specific serotonergic antidepressants (NaSSA) and serotonin and noradrenaline reuptake inhibitors (SNRIs). Agomelatine, a new melatonergic antidepressant, has been shown effective in various types of mood disorders. Moreover, some evidence points towards a possible efficacy of such a drug in the treatment of ADs. Therefore, the aim of this review was to elucidate current (facts and views) data on the role of agomelatine in the treatment of ADs. The trials evaluating agomelatine in the treatment of generalized anxiety disorder are few but, overall, encouraging in regards to its efficacy. However, further randomized, placebo-controlled studies on larger samples use are needed. Apart from some interesting case reports, no large studies are, to date, present in literature regarding agomelatine in the treatment of other ADs, such as panic disorder, social anxiety disorder, obsessive-compulsive disorder and post-traumatic stress disorder. Therefore, the clinical efficacy and the relative good tolerability of agomelatine in generalized anxiety (GAD) warrants further investigation in ADs.


Asunto(s)
Acetamidas/uso terapéutico , Ansiolíticos/uso terapéutico , Trastornos de Ansiedad/tratamiento farmacológico , Acetamidas/efectos adversos , Animales , Ansiolíticos/efectos adversos , Trastornos de Ansiedad/diagnóstico , Trastornos de Ansiedad/psicología , Humanos , Resultado del Tratamiento
11.
Sci Rep ; 12(1): 5015, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35322083

RESUMEN

It is crucial to control the tuning and improve the emission of a quantum emitter at the nanoscale. We report multiple Fano resonances in metallic nanostructures on an Er3+-doped tellurite glass. Periodic nanoslits were fabricated with a focused gallium ion beam on a gold thin film deposited on the tellurite glass. Is proposed a coupling function with Fano line-shape form, and the asymmetric parameter q for each resonance wavelength in the 515 to 535 nm region was calculated. This asymmetric resonance effect is a consequence of the quantum interaction between the continuum state, generated in the nanostructure, and the Stark splits of the [Formula: see text]H[Formula: see text] state.

12.
Int J Organ Transplant Med ; 13(1): 28-35, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37383419

RESUMEN

Background: This study aims to propose an initial development of the FACT-Liver Transplant (FACT-LT) scale to assess the major physical and emotional concerns of patients before and after Orthotopic Liver transplant (OLT) due to acute and chronic liver failure and hepatocellular carcinoma. Methods: The FACT-LT was developed in two phases. In Phase I, items were generated: 1) through interviews with 10 OLT experts and 15 candidates for or recipients of both oncological and non-oncological OLT which identified relevant topics; 2) from the FACIT item bank. In Phase II, a questionnaire to assess item frequency, applicability, and comprehension was administered to 20 OLT experts and, to assess item difficulty, embarrassment and content irrelevance, to 30 transplant recipients or candidate patients (15 oncological, 15 non-oncological). Results: In Phase I, 44 items were formulated/reviewed, and 30 items were maintained. All the healthcare professionals interviewed rejected the recommendation to develop two different modules for cancer and non-cancer patients. In Phase II, the majority of the experts and patients expressed an overall satisfaction with the questionnaire, indicating that the items were relevant, comprehensible and not embarrassing (range 75% - 99%). The first version of the FACT-LT includes 28 items defining four QOL domains: 5 items relating to Physical Well-Being, 8 to Functional Well-Being, 13 to Emotional Well-Being, and 2 to Social/Family Well-Being. Conclusion: The preliminary results obtained were promising; however further studies are needed, in order to proceed with a FACT-LT validation process.

13.
Environ Pollut ; 314: 120199, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36155226

RESUMEN

The waste-to-energy (WTE) incinerator plant located in the Turin area (Italy) started to recover energy from the combustion of municipal solid waste in 2013. A health surveillance program was implemented to evaluate the potential health effects on the population living near the plant. This program included a longitudinal biomonitoring to evaluate temporal changes of some environmental pollutants, including polycyclic aromatic hydrocarbons (PAHs), in residents living in areas near the Turin incinerator (exposed group, E) compared to those observed in subjects living far from the plant (not exposed group, NE). Ten monohydroxy-PAHs (OH-PAHs), consisting in the principal metabolites of naphthalene, fluorine, phenanthrene, and pyrene, were analyzed in urines collected from the E and NE subjects after one (T1) and three years (T2) of plant activity and compared with those determined in the same cohort established before the plant start-up (T0). Spearman correlation analysis was undertaken to explore possible associations between OH-PAHs and personal characteristics, lifestyle variables, and dietary habits. A linear mixed model (LMM) approach was applied to determine temporal trends of OH-PAHs observed in the E and NE subjects and to evaluate possible differences in trend between the two groups. Temporal trends of OH-PAHs determined by LMM analysis demonstrated that, at all times, the E group had concentrations lower than those assessed in the NE group, all other conditions being equal. Moreover, no increase in OH-PAH concentrations was observed at T1 and T2 either in E or in NE group. Significant positive correlations were found between all OH-PAHs and smoking habits. Regarding variables associated to outdoor PAH exposure, residence near high traffic roads and daily time in traffic road was positively correlated with 1-hydroxynaphthalene and 1-hydroxypyrene, respectively. In conclusion, no impact of the WTE plant on exposure to PAHs was observed on the population living near the plant.


Asunto(s)
Contaminantes Ambientales , Fenantrenos , Hidrocarburos Policíclicos Aromáticos , Humanos , Hidrocarburos Policíclicos Aromáticos/análisis , Monitoreo Biológico , Residuos Sólidos/análisis , Flúor/análisis , Monitoreo del Ambiente , Pirenos/análisis , Contaminantes Ambientales/análisis , Fenantrenos/análisis , Naftalenos/análisis , Biomarcadores
14.
Nature ; 438(7069): 785-91, 2005 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-16319827

RESUMEN

On the basis of previous ground-based and fly-by information, we knew that Titan's atmosphere was mainly nitrogen, with some methane, but its temperature and pressure profiles were poorly constrained because of uncertainties in the detailed composition. The extent of atmospheric electricity ('lightning') was also hitherto unknown. Here we report the temperature and density profiles, as determined by the Huygens Atmospheric Structure Instrument (HASI), from an altitude of 1,400 km down to the surface. In the upper part of the atmosphere, the temperature and density were both higher than expected. There is a lower ionospheric layer between 140 km and 40 km, with electrical conductivity peaking near 60 km. We may also have seen the signature of lightning. At the surface, the temperature was 93.65 +/- 0.25 K, and the pressure was 1,467 +/- 1 hPa.

15.
IEEE Trans Syst Man Cybern B Cybern ; 41(6): 1495-510, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21724519

RESUMEN

The high costs of development and maintenance of multimodal grammars in integrating and understanding input in multimodal interfaces lead to the investigation of novel algorithmic solutions in automating grammar generation and in updating processes. Many algorithms for context-free grammar inference have been developed in the natural language processing literature. An extension of these algorithms toward the inference of multimodal grammars is necessary for multimodal input processing. In this paper, we propose a novel grammar inference mechanism that allows us to learn a multimodal grammar from its positive samples of multimodal sentences. The algorithm first generates the multimodal grammar that is able to parse the positive samples of sentences and, afterward, makes use of two learning operators and the minimum description length metrics in improving the grammar description and in avoiding the over-generalization problem. The experimental results highlight the acceptable performances of the algorithm proposed in this paper since it has a very high probability of parsing valid sentences.

16.
Space Sci Rev ; 217(3): 48, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34776548

RESUMEN

NASA's Mars 2020 (M2020) rover mission includes a suite of sensors to monitor current environmental conditions near the surface of Mars and to constrain bulk aerosol properties from changes in atmospheric radiation at the surface. The Mars Environmental Dynamics Analyzer (MEDA) consists of a set of meteorological sensors including wind sensor, a barometer, a relative humidity sensor, a set of 5 thermocouples to measure atmospheric temperature at ∼1.5 m and ∼0.5 m above the surface, a set of thermopiles to characterize the thermal IR brightness temperatures of the surface and the lower atmosphere. MEDA adds a radiation and dust sensor to monitor the optical atmospheric properties that can be used to infer bulk aerosol physical properties such as particle size distribution, non-sphericity, and concentration. The MEDA package and its scientific purpose are described in this document as well as how it responded to the calibration tests and how it helps prepare for the human exploration of Mars. A comparison is also presented to previous environmental monitoring payloads landed on Mars on the Viking, Pathfinder, Phoenix, MSL, and InSight spacecraft.

17.
Phys Rev Lett ; 104(25): 253603, 2010 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-20867377

RESUMEN

We present a new technique, differential ghost imaging (DGI), which dramatically enhances the signal-to-noise ratio (SNR) of imaging methods based on spatially correlated beams. DGI can measure the transmission function of an object in absolute units, with a SNR that can be orders of magnitude higher than the one achievable with the conventional ghost imaging (GI) analysis. This feature allows for the first time, to our knowledge, the imaging of weakly absorbing objects, which represents a breakthrough for GI applications. Theoretical analysis and experimental and numerical data assessing the performances of the technique are presented.

18.
Psychol Med ; 40(1): 117-24, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19419593

RESUMEN

BACKGROUND: Worry is considered a key feature of generalized anxiety disorder (GAD), whose neural correlates are poorly understood. It is not known whether the brain regions involved in pathological worry are similar to those involved in worry-like mental activity in normal subjects or whether brain areas associated with worry are the same for different triggers such as verbal stimuli or faces. This study was designed to clarify these issues. METHOD: Eight subjects with GAD and 12 normal controls underwent functional magnetic resonance imaging (fMRI) mood induction paradigms based on spoken sentences or faces. Sentences were either neutral or designed to induce worry. Faces conveyed a sad or a neutral mood and subjects were instructed to empathize with those moods. RESULTS: We found that the anterior cingulate and dorsal medial prefrontal cortex [Brodmann area (BA) 32/23 and BA 10/11] were associated with worry triggered by sentences in both subjects with GAD and normal controls. However, GAD subjects showed a persistent activation of these areas even during resting state scans that followed the worrying phase, activation that correlated with scores on the Penn State Worry Questionnaire (PSWQ). This region was activated during the empathy experiment for sad faces. CONCLUSIONS: The results show that worry in normal subjects and in subjects with GAD is based on activation of the medial prefrontal and anterior cingulate regions, known to be involved in mentalization and introspective thinking. A dysregulation of the activity of this region and its circuitry may underpin the inability of GAD patients to stop worrying.


Asunto(s)
Afecto/fisiología , Trastornos de Ansiedad/fisiopatología , Encéfalo/fisiopatología , Imagen por Resonancia Magnética , Adolescente , Adulto , Trastornos de Ansiedad/psicología , Mapeo Encefálico , Dominancia Cerebral/fisiología , Empatía , Femenino , Giro del Cíngulo/fisiopatología , Humanos , Italia , Masculino , Inventario de Personalidad , Corteza Prefrontal/fisiopatología , Valores de Referencia , Estudiantes/psicología , Teoría de la Mente , Adulto Joven
19.
Exp Brain Res ; 205(3): 307-24, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20680252

RESUMEN

Graceful aging has been associated with frontal hyperactivations in working- and episodic long-term memory tasks, a compensatory process, according to some, that allows the best normal elders to perform these tasks at a juvenile level, in spite of natural cortical impoverishment. In this study, 24 young and 24 healthy elderly participants were compared. Graceful aging was explored by investigating domains where most healthy elders perform like youngers (e.g. lexical-semantic knowledge) and tasks that are typically more challenging, like episodic long-term recognition memory tasks. With voxel-based morphometry, we also studied to what extent changes of fMRI activation were consistent with the pattern of brain atrophy. We found that hyperactivations and hypoactivations of the elders were not restricted to the frontal lobes, rather they presented with task-dependent patterns. Only hypoactivations and normal levels of activation systematically overlapped with regional atrophy. We conclude that compensatory processes associated with graceful aging may not necessarily be a sign of early saturation of executive resources, if this was to be represented by a systematic frontal hyperactivation, but rather they may represent the ability of recruiting new cognitive strategies. We discuss two possible approaches to further test this hypothesis.


Asunto(s)
Envejecimiento/psicología , Adulto , Anciano , Atrofia , Encéfalo/patología , Mapeo Encefálico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Memoria/fisiología , Persona de Mediana Edad , Red Nerviosa/crecimiento & desarrollo , Red Nerviosa/fisiología , Pruebas Neuropsicológicas , Oxígeno/sangre , Corteza Prefrontal/crecimiento & desarrollo , Corteza Prefrontal/fisiología , Desempeño Psicomotor/fisiología , Reconocimiento en Psicología/fisiología , Percepción Visual/fisiología
20.
Neuropsychologia ; 147: 107579, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32758552

RESUMEN

The space surrounding our body, defined as peripersonal space (PPS), is dynamically shaped by our motor experiences. For instance, PPS extends after using a tool to reach far objects. Several studies have demonstrated how PPS size varies across people, depending on different individual characteristics, including schizotypy. Coherently, narrower PPS boundaries have been reported among high schizotypal individuals and schizophrenia patients. However, little is known about the relationship between PPS plasticity and personality traits like schizotypy. To this purpose, the present study has investigated the individual PPS plasticity, after two different motor trainings, along the schizotypal continuum. Specifically, PPS plasticity was tested after using a tool (Experiment 1) and after the mere observation of another person using the same tool (Experiment 2). Indeed, previous evidence has shown that tool-use observation influences visual distance judgments, extending the representation of PPS. To date, however, there is no study investigating whether observation of tools action could also affect multisensory PPS tasks. Experiment 1 has shown that PPS boundaries extended after using the tool; on the other hand, Experiment 2 has revealed the absence of PPS expansion. Moreover, greater PPS expansion emerged in the relatively-low schizotypal group than in the relatively-high one, regardless of the type of motor training performed. The absence of PPS modulation after the observation task is discussed in relation to recent findings showing that intentional action and/or the goal of the action represent potentially crucial elements to trigger PPS plasticity. Finally, these new results extend previous evidence underlining a potential general functional alteration of PPS with the increase of schizotypal level.


Asunto(s)
Espacio Personal , Trastorno de la Personalidad Esquizotípica , Humanos , Individualidad , Estimulación Física , Percepción Espacial
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