Cerebral Blood Volume Changes in Negative Bold Regions during Visual Stimulation in Humans at 7t
نویسندگان
چکیده
HUMANS AT 7T Laurentius Huber, Jozien Goense, Dimo Ivanov, Steffen N. Krieger, Robert Turner, and Harald E. Moeller NMR-Unit, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Tübingen, Germany, Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, Cognitive and Clinical Neuroscience, Maastricht University, Maastricht, Netherlands
منابع مشابه
Origin of negative blood oxygenation level-dependent fMRI signals.
Functional magnetic resonance imaging (fMRI) techniques are based on the assumption that changes in spike activity are accompanied by modulation in the blood oxygenation level-dependent (BOLD) signal. In addition to conventional increases in BOLD signals, sustained negative BOLD signal changes are occasionally observed and are thought to reflect a decrease in neural activity. In this study, the...
متن کاملIncreases in oxygen consumption without cerebral blood volume change during visual stimulation under hypotension condition.
The magnitude of the blood oxygenation level-dependent (BOLD) signal depends on cerebral blood flow (CBF), cerebral blood volume (CBV) and cerebral metabolic rate of oxygen (CMRO2). Thus, it is difficult to separate CMRO2 changes from CBF and CBV changes. To detect the BOLD signal changes induced only by CMRO2 responses without significant evoked CBF and CBV changes, BOLD and CBV functional mag...
متن کاملSources of phase changes in BOLD and CBV-weighted fMRI.
Phase changes in blood oxygenation-level dependent (BOLD) fMRI have been observed in humans; however, their exact origin has not yet been fully elucidated. To investigate this issue, we acquired gradient-echo (GE) BOLD and cerebral blood volume (CBV)-weighted fMRI data in anesthetized cats during visual stimulation at 4.7T and 9.4T, before and after injection of a superparamagnetic contrast age...
متن کاملThe BOLD Plot Thickens: Sign- and Layer-Dependent Hemodynamic Changes with Activation
In this issue of Neuron, Goense et al. (2012) report on high-resolution, layer-specific measurements of BOLD, cerebral blood volume, and cerebral blood flow in regions of positive and negative BOLD associated with a simple visual stimulus. The findings strongly suggest that the hemodynamic mechanisms behind negative signal changes are quite different from those behind positive signal changes.
متن کاملHemodynamic changes after visual stimulation and breath holding provide evidence for an uncoupling of cerebral blood flow and volume from oxygen metabolism.
Functional neuroimaging is most commonly performed using the blood-oxygenation-level-dependent (BOLD) approach, which is sensitive to changes in cerebral blood flow (CBF), cerebral blood volume (CBV), and the cerebral metabolic rate of oxygen (CMRO(2)). However, the precise mechanism by which neuronal activity elicits a hemodynamic response remains controversial. Here, visual stimulation (14 se...
متن کامل