96 research outputs found

    Deficits in inhibitory control and conflict resolution on cognitive and motor tasks in Parkinson's disease

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    Recent imaging studies in healthy controls with a conditional stop signal reaction time (RT) task have implicated the subthalamic nucleus (STN) in response inhibition and the pre-supplementary motor area (pre-SMA) in conflict resolution. Parkinson's disease (PD) is characterized by striatal dopamine deficiency and overactivity of the STN and underactivation of the pre-SMA during movement. We used the conditional stop signal RT task to investigate whether PD produced similar or dissociable effects on response initiation, response inhibition and response initiation under conflict. In addition, we also examined inhibition of prepotent responses on three cognitive tasks: the Stroop, random number generation and Hayling sentence completion. PD patients were impaired on the conditional stop signal reaction time task, with response initiation both in situations with or without conflict and response inhibition all being significantly delayed, and had significantly greater difficulty in suppressing prepotent or habitual responses on the Stroop, Hayling and random number generation tasks relative to controls. These results demonstrate the existence of a generalized inhibitory deficit in PD, which suggest that PD is a disorder of inhibition as well as activation and that in situations of conflict, executive control over responses is compromised.This work was supported by a PhD studentship from Fundación Caja Madrid (IO), a Career Development Fellowship from the Parkinson’s disease Society (LW) and a Royal Society Travelling Fellowship.Peer reviewe

    Differences in Cortical Structure and Functional MRI Connectivity in High Functioning Autism

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    Autism spectrum disorders (ASD) represent a complex group of neurodevelopmental conditions characterized by deficits in communication and social behaviors. We examined the functional connectivity (FC) of the default mode network (DMN) and its relation to multimodal morphometry to investigate superregional, system-level alterations in a group of 22 adolescents and young adults with high-functioning autism compared to age-, and intelligence quotient-matched 29 healthy controls. The main findings were that ASD patients had gray matter (GM) reduction, decreased cortical thickness and larger cortical surface areas in several brain regions, including the cingulate, temporal lobes, and amygdala, as well as increased gyrification in regions associated with encoding visual memories and areas of the sensorimotor component of the DMN, more pronounced in the left hemisphere. Moreover, patients with ASD had decreased connectivity between the posterior cingulate cortex, and areas of the executive control component of the DMN and increased FC between the anteromedial prefrontal cortex and areas of the sensorimotor component of the DMN. Reduced cortical thickness in the right inferior frontal lobe correlated with higher social impairment according to the scores of the Autism Diagnostic Interview-Revised (ADI-R). Reduced cortical thickness in left frontal regions, as well as an increased cortical thickness in the right temporal pole and posterior cingulate, were associated with worse scores on the communication domain of the ADI-R. We found no association between scores on the restrictive and repetitive behaviors domain of ADI-R with structural measures or FC. The combination of these structural and connectivity abnormalities may help to explain some of the core behaviors in high-functioning ASD and need to be investigated further

    On-Line Metrology with Conoscopic Holography: Beyond Triangulation

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    On-line non-contact surface inspection with high precision is still an open problem. Laser triangulation techniques are the most common solution for this kind of systems, but there exist fundamental limitations to their applicability when high precisions, long standoffs or large apertures are needed, and when there are difficult operating conditions. Other methods are, in general, not applicable in hostile environments or inadequate for on-line measurement. In this paper we review the latest research in Conoscopic Holography, an interferometric technique that has been applied successfully in this kind of applications, ranging from submicrometric roughness measurements, to long standoff sensors for surface defect detection in steel at high temperatures

    Cognitive Reserve in Parkinson's Disease without Dementia: β-Amyloid and Metabolic Assessment

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    [Background] Cognitive reserve (CR) is the mismatch between preserved cognition and neuropathological damage. Amyloidopathy in Parkinson's disease (PD) could be associated with faster progression to dementia, but the putative protective effect of CR is unknown.[Objectives] To evaluate the effect of CR on β-amyloid burden and brain metabolism in non-demented PD subjects.[Methods] Participants with PD (n = 53) underwent a clinical evaluation, [18F]-fluorodeoxyglucose and [18F]-flutemetamol positron emission tomography magnetic resonances, and were classified according to CR. The metabolic pattern of 16 controls was compared to PD subjects.[Results] The PD subjects showed hypometabolism mainly in the bilateral posterior cortex. Superior-CR subjects (n = 22) exhibited better cognitive performance, increased amyloid burden, and higher metabolism in several right hemisphere areas compared to low-medium-CR subjects (n = 31).[Conclusions] Higher CR in non-demented PD is associated with better cognitive performance, which might reduce vulnerability to the effect of β-amyloid. Whether superior CR leads to protection against metabolic deterioration, and predominantly right hemisphere involvement, deserves further exploration.PET-magnetic resonance studies were funded by the collaboration agreement between General Electric, Siemens Health-care S.L.U., HM Hospitales 1989 S.A., and Fundación de Investigación HM Hospitales.Peer reviewe

    Focused ultrasound subthalamotomy in patients with asymmetric Parkinson's disease: a pilot study

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    Ablative neurosurgery has been used to treat Parkinson's disease for many decades. MRI-guided focused ultrasound allows focal lesions to be made in deep brain structures without skull incision. We investigated the safety and preliminary efficacy of unilateral subthalamotomy by focused ultrasound in Parkinson's disease.Fundación de investigación HM Hospitales and Insightec.Peer reviewe

    Prospective Long-term Follow-up of Focused Ultrasound Unilateral Subthalamotomy for Parkinson Disease

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    Unilateral magnetic resonance-guided focused ultrasound subthalamotomy (FUS-STN) has been shown to improve the cardinal motor features of Parkinson disease (PD). Whether this effect is sustained is not known. This study aims to report the long-term outcome of patients with PD treated with unilateral FUS-STN.Peer reviewe

    Unilateral focused ultrasound subthalamotomy in early Parkinson's disease: a pilot study

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    [Background] Unilateral focused ultrasound subthalamotomy (FUS-STN) improves motor features of Parkinson’s disease (PD) in moderately advanced patients. The less invasive nature of FUS makes its early application in PD feasible. We aim to assess the safety and efficacy of unilateral FUS-STN in patients with PD of less than 5 years from diagnosis (early PD).[Methods] Prospective, open-label study. Eligible patients with early PD had highly asymmetrical cardinal features. The primary outcome was safety, defined as treatment-related adverse events at 6 months. Secondary outcomes included efficacy, assessed as motor improvement in the Movement Disorders Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), motor fluctuations, non-motor symptoms, daily living activities, quality of life, medication and patients’ impression of change.[Results] Twelve patients with PD (median age 52.0 (IQR 49.8–55.3) years, median time from diagnosis 3.0 (2.1–3.9) years) underwent unilateral FUS-STN. Within 2 weeks after treatment, five patients developed dyskinesia on the treated side, all resolved after levodopa dose adjustment. One patient developed mild contralateral motor weakness which fully resolved in 4 weeks. One patient developed dystonic foot and another hand and foot dystonia. The latter impaired gait and became functionally disabling initially. Both cases were well controlled with botulinum toxin injections. The off-medication motor MDS-UPDRS score for the treated side improved at 12 months by 68.7% (from 14.5 to 4.0, p=0.002), and the total motor MDS-UPDRS improved by 49.0% (from 26.5 to 13.0, p=0.002). Eleven patients (92%) reported global improvement 12 months after treatment.[Conclusion] Unilateral FUS-STN may be safe and effective to treat motor manifestations in patients with early PD. A larger confirmatory trial is warranted.[Trial registration number] NCT04692116.This study was supported by Fundación de Investigación HM Hospitales and Fundación MAPFRE. ENV was supported in 2021 for this specific project by a fellowship from the Movement Disorders Group of the Spanish Neurology Society (Sociedad Española de Neurología, SEN) granted by Zambon.Peer reviewe

    Cognitive safety after unilateral magnetic resonance-guided focused ultrasound thalamotomy for essential tremor

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    Essential tremor (ET) is the most common movement disorder, affecting 1% of the population worldwide. There is sound evidence that medically refractory tremor improves with thalamotomy and deep brain stimulation (DBS) targeting the thalamic ventralis intermedius nucleus (VIM). In the last few years, the incisionless technique of magnetic resonance- guided focused ultrasound (MRgFUS) has been demonstrated to be an effective procedure for unilateral thalamotomy,1 with a positive profile with regard to side effects. The thalamus is involved in cognitive functions such as attention/executive control, memory and language. Focal ablation of the thalamus, even when targeting a sensorimotor region as the VIM, raises question about potential cognitive side effects. After unilateral VIM-DBS in 40 patients with ET, Fields et al2 showed statistically significant improvements in visuoperceptual function and verbal memory. There was no significant decline in any measure, but four patients with preoperative low verbal fluency showed a further decline. Most studies have shown reduced verbal fluency under active VIM-DBS.2–4 Since focused ultrasound thalamotomy is a less invasive procedure, we hypothesised that the risk of procedure-related cognitive decline is further reduced.Peer reviewe

    Bilateral staged magnetic resonance-guided focused ultrasound thalamotomy for the treatment of essential tremor: a case series study

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    Unilateral magnetic resonance-guided focused ultrasound (FUS) thalamotomy is efficacious for the treatment of medically refractory essential tremor (ET). Viability of bilateral FUS ablation is unexplored.This study was supported by the Fundación de Investigación HM Hospitales and InSightec, which provided funding for performance of ultrasound procedures.Peer reviewe

    Revista de Vertebrados de la Estación Biológica de Doñana

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    The Osteology of Barbus bocagei (Steindachner, 1866) (Pisces: Cyprinidae).El crecimiento del Cacho (Leuciscus cephalus pyraenaicus Günther, 1862) en el rio Jarama (cuenca del Tajo)Contribución al estudio de la bermejuela, Rutilus arcasi, Steindachner 1866 de la cuenca del Júcar (Osteichthyes: Cyprinidae) 1. MorfometríaDimensiones, estructura, forma y disposición en la cavidad de los nidos de Corvus monedula.Variaciones altitudinales en la composición de las comunidades nidificantes de aves de Sierra Nevada (Sur de España)Ecomorfología de una comunidadde Passeriformes en la Sierra de Cazorla, SE de EspañaLa Distribución del pez-sol (Lepolllis gibbostlS L.) en la Península IbéricaSobre la distribución de Barbus haasi (OSTARIOPHYSI: CYPRINIDAE)La Distribución de Barbus bocagei STEINDACHNER, 1865 (OSTARIOPHYSI: CYPRINIDAE) en la Península IbéricaLighy effects on circadian locomotor activity of Lacerta lepida under constant temperatureEvaluación de diferentes métodos para estimar el área de campeo de dos especies de iguánidos.Un Casal de Cartaxo-Nottenho (Saxicola rubetra) a criar em Portugal.Nidificación de Passer hispaniolensis en antiguos nidos de Dendrocopos major thanneri.Observación de un lince ibérico (Lynx pardina) en la provincia de Lugo. Norte de España.El Visón americano, Mustela vison SCHREBER, 1777 (MAMMALIA, MUSTELIDAE) en Cataluña, N.E. de la Península Ibérica.Peer reviewe
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