Search results for "brain"
showing 10 items of 3997 documents
Voluntary and Involuntary Attention in Bistable Visual Perception: A MEG Study
2020
In this study, voluntary and involuntary visual attention focused on different interpretations of a bistable image, were investigated using magnetoencephalography (MEG). A Necker cube with sinusoidally modulated pixels' intensity in the front and rear faces with frequencies 6.67 Hz (60/9) and 8.57 Hz (60/7), respectively, was presented to 12 healthy volunteers, who interpreted the cube as either left- or right-oriented. The tags of these frequencies and their second harmonics were identified in the average Fourier spectra of the MEG data recorded from the visual cortex. In the first part of the experiment, the subjects were asked to voluntarily control their attention by interpreting the cu…
Effects of High Frequency Repetitive Transcranial Magnetic Stimulation (HF-rTMS) on Delay Discounting in Major Depressive Disorder: An Open-Label Unc…
2019
Background: Delay discounting (DD) refers to the decrease of a present subjective value of a future reward as the delay of its delivery increases. Major depressive disorder (MDD), besides core emotional and physical symptoms, involves difficulties in reward processing. Depressed patients often display greater temporal discounting rates than healthy subjects. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique applied in several countries to adult patients with treatment resistant depression. Studies suggest that this technique can be used to modulate DD, but no trial has assessed its effects on depressed patients. Methods: In this open-label unc…
Reaching and Grasping a Glass of Water by Locked-In ALS Patients through a BCI-Controlled Humanoid Robot
2017
Locked-in Amyotrophic Lateral Sclerosis (ALS) patients are fully dependent on caregivers for any daily need. At this stage, basic communication and environmental control may not be possible even with commonly used augmentative and alternative communication devices. Brain Computer Interface (BCI) technology allows users to modulate brain activity for communication and control of machines and devices, without requiring a motor control. In the last several years, numerous articles have described how persons with ALS could effectively use BCIs for different goals, usually spelling. In the present study, locked-in ALS patients used a BCI system to directly control the humanoid robot NAO (Aldebar…
Signaling through BMPR-IA regulates quiescence and long-term activity of neural stem cells in the adult hippocampus.
2010
SummaryNeural stem cells (NSCs) in the adult hippocampus divide infrequently, and the molecules that modulate their quiescence are largely unknown. Here, we show that bone morphogenetic protein (BMP) signaling is active in hippocampal NSCs, downstream of BMPR-IA. BMPs reversibly diminish proliferation of cultured NSCs while maintaining their undifferentiated state. In vivo, acute blockade of BMP signaling in the hippocampus by intracerebral infusion of Noggin first recruits quiescent NSCs into the cycle and increases neurogenesis; subsequently, it leads to decreased stem cell division and depletion of precursors and newborn neurons. Consistently, selective ablation of Bmpr1a in hippocampal …
Infections of susceptible and resistant mouse strains with herpes simplex virus type 1 and 2.
1980
The spread of HSV of type 1 and 2 was investigated after intraperitoneal, intraplantar and intracerebral infections of resistant (C57/bl) and susceptible (NMRI) mice. The virus spreads after i.p. infection to the spleen and the liver to the same extent in both strains of mice. However, virus is eliminated earlier in resistant mice. Intracerebral infections revealed a peculiar type of resistance of C57/bl mice especially for type 2 of HSV. HSV multiplies in the thymus at the early stage of infection and can be detected in this organ in sick mice of NMRI strain. HSV-1 and 2 can be detected in the spinal cord of C57/bl mice without sickness or death of these animals.
Sterol Regulatory Element Binding Transcription Factor-1 Gene Variation and Medication Load Influence White Matter Structure in Schizophrenia
2014
<b><i>Background:</i></b> Diffusion tensor imaging (DTI) studies have shown a widespread disruption of white matter (WM) microstructure in schizophrenia. Furthermore, higher fractional anisotropy (FA) has been consistently correlated with the severity of psychotic symptoms. Antipsychotic drugs (APDs) affect lipid homeostasis. Gene polymorphisms in sterol regulatory element binding transcription factor (SREBF)-1 and SREBF-2 have been associated with schizophrenia. <b><i>Methods:</i></b> In a sample of 65 patients affected by chronic schizophrenia, we investigated the effect of ongoing APD medication, SREBF-1 rs11868035<b> </b>polymo…
The Effect of Dexamethasone on Water and Electrolyte Content and on rCBF in Perifocal Brain Edema in Man
1972
The results of clinical studies are reported dealing with the relationship between cerebral edema and regional cerebral blood flow in patients with brain tumor as well as with the effect of dexamethasone on this relationship. rCBF is found to be significantly reduced in brain tissue surrounding brain tumors. Autoregulation as well as cerebrovascular reactivity to PaCO2 is focally or generally impaired. Water content of perifocal white matter is markedly increased. The combination of tissue lactacidosis, low regional blood flow and vasoparalysis seems to be a characteristic finding in this type of local brain edema. The increased local tissue pressure, due to the increased tissue water conte…
Selected Age-Related Disorders
2013
Aged human individuals are frequently affected by various age-related impairments and disorders at once (multimorbidity) making it difficult to investigate and understand the link between aging as key risk factor and single syndromes. In some chapters of this book links have been identified between molecular mechanisms of aging and the pathogenesis of human disorders in the elderly. Here, the focus is put on Alzheimers disease (AD) and cancer. While cancer in many cases can successfully be treated and sometimes even cured by pharmacology and/or surgery, AD is still an incurable deadly disease. Like almost no other disorder the onset of AD is strictly associated with higher age and experienc…
Cessation of Cerebral Blood Flow in Total Irreversible Loss of Brain Function
1969
After the demonstration, by our group [3, 4], that in cases of so-called “cerebral death” there is an absence of clearance from the brain of 133Xe selectively injected into the internal carotid artery, further attention was dedicated to establish possible sources of error in this technique.
Relationship between Diabetes and Ischemic Stroke: Analysis of Diabetes- Related Risk Factors for Stroke and of Specific Patterns of Stroke Associate…
2015
Diabetes and ischemic stroke are common diseases that frequently occurring together. Among patients with diabetes mellitus several factors contribute in varying degrees to the overall cerebrovascular risk including hyperglycemia, vascular risk factors such as hypertension and dyslipidemia and also genetic, demographic, and lifestyle factors and several studies have shown that people with diabetes have approximately twice the risk of ischemic stroke compared with those without diabetes. The association between ischemic stroke and diabetes is bidirectional and it is not limited to acute ischemic stroke since diabetes may contribute to a more insidious brain damage represented by lacunar infar…