Search results for "cortex"
showing 10 items of 1827 documents
A histological study of a femur of Plagiosuchus, a Middle Triassic temnospondyl amphibian from southern GEmany, using thin sections and micro-CT scan…
2013
AbstractThe histology of a femur of Plagiosuchus, a Middle Triassic temnospondyl amphibian, is described on the basis of two supplementary methods: classic thin sectioning and micro-CT scanning. In addition, the effectiveness of high-resolution micro-CT scanning for histological analysis is assessed. A classic, mid-shaft thin section of the femur was prepared, but prior to slicing two micro-CT scans were made. One of these has an image stack of a total of 1,024 images in the horizontal plane and a slice thickness of 87.8 μm, so that the entire bone could be captured, while the second was at mid-shaft region only, yet with a higher resolution of 28.3 μm and an image stack of 787 images in th…
Doublecortin expression in the adult rat telencephalon
2001
Doublecortin (DCX) is a protein required for normal neuronal migration in the developing cerebral cortex, where it is widely expressed in both radially and tangentially migrating neuroblasts. Moreover, it has been observed in the adult rostral migratory stream, which contains the neuronal precursors traveling to the olfactory bulb. We have performed DCX immunocytochemistry in the adult rat brain to identify precisely the neuronal populations expressing this protein. Our observations confirm the presence of DCX immunoreactive cells with the characteristic morphology of migrating neuroblasts in the subventricular zone, rostral migratory stream and the main and accessory olfactory bulbs. We ha…
Extremely Low Frequency Magnetic Fields Do Not Affect LTP-Like Plasticity in Healthy Humans.
2020
Introduction: Several studies explored, in vitro, the biological effects of extremely low-frequency magnetic fields (ELF-MFs) and reported the induction of functional changes in neuronal activity. In particular, ELF-MFs can influence synaptic plasticity both in-vitro and in animal models. Indeed, some studies reported an increase in long-term potentiation (LTP) whereas others suggested its reduction. However, no specific study has investigated such effect in humans. Aims: To evaluate whether ELF-MFs affect the propensity of the human cortex to undergo LTP-like plasticity. Methods: We designed a randomized, single-blind, sham-controlled, cross-over study on 10 healthy subjects. Cortical plas…
23. Resting state functional magnetic resonance imaging analysis of the brain of pathological gamblers
2018
Purpose Gambling disorder has been recently reclassified under the category “substance-related and addictive disorders”. Recent studies performed through functional MRI (fMRI) have shown that the perseverance of some behaviors can alter brain activation [1] , [2] . In this work we aim at investigating functional connectivity changes in pathological gamblers (PGs) in comparison to healthy controls (HCs) by means of resting state functional Magnetic Resonance Imaging (rs-fMRI). Methods and materials Thirteen HCs and fourteen PGs were recruited (all right handed males; drugs free; mean age 36 ± 10 yrs). All acquisitions were performed through a 1,5 T MRI scanner using a 8-channels phased-array…
An exploration of anger phenomenology in multiple sclerosis
2009
Background and purpose: Multiple sclerosis (MS) patients are often emotionally disturbed. We investigated anger in these patients in relation to demographic, clinical, and mood characteristics. Patients and methods: About 195 cognitively unimpaired MS patients (150 relapsing–remitting and 45 progressive) were evaluated with the State Trait Anger Expression Inventory, the Chicago Multiscale Depression Inventory, and the State Trait Anxiety Inventory. The patients’ anger score distribution was compared with that of the normal Italian population. Correlation coefficients among scale scores were calculated and mean anger scores were compared across different groups of patients by analysis of …
Dauer epileptischer Anfälle während selektiver pharyngealer Hirnkühlung / Duration of induced seizures during selective pharyngeal brain cooling
2004
Whole body hypothermia can be used to treat the injured brain (e.g. after hypoxic events). Side effects include hemodynamic instability, coagulopathy and infection. Because of these side effects it appears reasonable to cool the brain selectively (selective brain cooling, SBC) without changing the core temperature. A new animal model was used to demonstrate SBC from the pharynx and to examine effects of SBC on the duration of pharmacologically induced seizure activity. Sprague-Dawley rats (n=18, 12 successful experiments) were sedated and mechanically ventilated. Invasive blood pressure monitoring was instituted and blood gases were drawn to evaluate the arterial blood gas status. Electrica…
Lesions to the posterior insular cortex cause dysarthria
2011
Background: Up to now, there are few systematic studies in a sufficient number of patients with lesions involving the insular cortex (IC) examining whether damage of the IC is directly related to dysarthria. Thus, this is the first study applying modern voxel-lesion behaviour mapping (VLBM) aimed to examine whether the IC is involved in dysarthria – and if so – which part of the IC is involved. Methods: Twenty-five patients with acute stroke lesions affecting the IC and peri-insular region were investigated employing VLBM analysis. Results: Present data indicated that dysarthria is associated with stroke lesions affecting the right- and left-sided posterior IC. Conclusions: Owing to the…
Visual Cortex Performs a Sort of Non-linear ICA
2010
Here, the standard V1 cortex model optimized to reproduce image distortion psychophysics is shown to have nice statistical properties, e.g. approximate factorization of the PDF of natural images. These results confirm the efficient encoding hypothesis that aims to explain the organization of biological sensors by information theory arguments.
Tissue Oxygenation in Normal and Edematous Brain Cortex During Arterial Hypocapnia
1984
Since arterial hypocapnia causes a cerebral blood flow decrease, hypocapnic conditions are induced in patients with severe traumatic brain injury by controlled hyperventilation in order to reduce the intracranial pressure (Gordon, 1971). Beneficial effects on the clinical course of patients, however, can be observed only under conditions of moderate hypocapnia. As shown by animal experiments severe arterial hypocapnia results in insufficient oxygen supply conditions in brain tissue (Grote et al., 1981), which subsequently influences the brain metabolism (Granholm et al., 1969, 1971) and counteracts the influence of hypocapnia on cerebral blood flow regulation (Grote et al., 1981). The prese…
Cellular Acetylcholine Receptor Expression in the Brain of Patients with Alzheimer’s and Parkinson’s Dementia
1995
Binding studies and receptor autoradiography reveal the overall changes of acetylcholine receptors (AChR) in Alzheimer’s and Parkinson’s dementia cortices.2,5 A detailed account of these changes requires a study of neurochemical phenotype of individual neurons as basic elements of networks constituting the substrate of cortical functions.4 Examples will be given for cell-type specific AChR localization in normal and diseased human cerebral cortex.