Search results for "Insula"
showing 10 items of 735 documents
Amphibians and squamate reptiles from the stratigraphic unit Xb of El Salt (Middle Palaeolithic; Alcoy, Spain): palaeoenvironmental and palaeoclimati…
2020
The locality of El Salt (Middle Paleolithic, Alcoy, Spain) is mainly known by having one of the youngest Neanderthals records of the southeastern Iberian Peninsula. In this work, we have analysed the herpetofaunal fossils from the upper part of stratigraphic unit Xb, dated at 52.3 ± 4.6 ka (MIS 3). The faunal list is composed by three taxa of anurans (Alyte obstetricans, Bufo bufo s.l., and Epidalea calamita), one taxon of blanid (Blanus cinereus s.l.), two taxa of lizards (Chalcides bedriagai and cf. Acanthodactylus erythrurus), and one taxon of snakes (cf. Rhinechis scalaris). All of them have a broad distribution range in the Mediterranean, with wide ecological preferences range. This as…
Direction-dependent activation of the insular cortex during vertical and horizontal hand movements
2016
International audience; The planning of any motor action requires a complex multisensory processing by the brain. Gravity - immutable on Earth - has been shown to be a key input to these mechanisms. Seminal fMRI studies performed during visual perception of falling objects and self-motion demonstrated that humans represent the action of gravity in parts of the cortical vestibular system; in particular, the insular cortex and the cerebellum. However, little is known as to whether a specific neural network is engaged when processing non-visual signals relevant to gravity. We asked participants to perform vertical and horizontal hand movements without visual control, while lying in a 3T-MRI sc…
Large-scale network architecture and associated structural cortico-subcortical abnormalities in patients with sleep/awake-related seizures.
2019
Study objectives In this study, we aimed to estimate the alterations of brain networks and structural integrity linked to seizure occurrence during sleep and awake states. Methods Using a graph theory approach to magnetic resonance imaging-derived volumes of cortical and subcortical regions, we investigated the topological organization of structural networks in patients with sleep seizures (n = 13), patients with awake seizures (n = 12), and age- and sex-matched healthy controls (n = 10). Abnormalities in regional structural substrates (cortical volume/surface area, subcortical volumes) associated with sleep seizures and awake seizures were further analyzed. Results Brain networks in patien…
Frontal hypoactivation and alterations in the reward-system during humor processing in patients with schizophrenia spectrum disorders
2018
Humor is a ubiquitous human ability with important implications for both social and emotional functioning. Patients with neuropsychiatric disorders, such as schizophrenia, experience difficulties in the comprehension and appreciation of humor. However, the specific neural mechanisms underlying these deficits are unknown. In the current study, we sought to elucidate the neural correlates of humor processing in patients with schizophrenia spectrum disorders (SSD). Functional Magnetic Resonance Imaging (fMRI) was used in thirty-one patients with SSD and a control group, performing a humor processing paradigm. Both regional brain activation and parametric modulation of brain responses via subje…
High opiate receptor binding potential in the human lateral pain system
2005
To determine how opiate receptor distribution is co-localized with the distribution of nociceptive areas in the human brain, eleven male healthy volunteers underwent one PET scan with the subtype-nonselective opioidergic radioligand [(18)F]fluoroethyl-diprenorphine under resting conditions. The binding potential (BP), a parameter for the regional cerebral opioid receptor availability, was computed using the occipital cortex as reference region. The following regions of interest (ROIs) were defined on individual MR images: thalamus, sensory motor strip (SI/MI area), frontal operculum, parietal operculum, anterior insular cortex, posterior insular cortex, anterior cingulate cortex (ACC; peri-…
Don't stress, it's under control: Neural correlates of stressor controllability in humans
2021
Abstract Animal research has repeatedly shown that control is a key variable in the brain's stress response. Uncontrollable stress triggers a release of monoamines, impairing prefrontal functions while enhancing subcortical circuits. Conversely, control over an adverse event involves prefrontally mediated downregulation of monoamine nuclei and is considered protective. However, it remains unclear to what extent these findings translate to humans. During functional magnetic resonance imaging, we subjected participants to controllable and uncontrollable aversive but non-painful electric stimuli, as well as to a control condition without aversive stimulation. In each trial, a symbol signalled …
Neural correlates of hemispheric dominance and ipsilaterality within the vestibularsystem
2007
Earlier functional imaging studies on the processing of vestibular information mainly focused on cortical activations due to stimulation of the horizontal semicircular canals in right-handers. Two factors were found to determine its processing in the temporo-parietal cortex: a dominance of the non-dominant hemisphere and an ipsilaterality of the neural pathways. In an investigation of the role of these factors in the vestibular otoliths, we used vestibular evoked myogenic potentials (VEMPs) in a fMRI study of monaural saccular-otolith stimulation. Our aim was to (1) analyze the hemispheric dominance for saccular-otolith information in healthy left-handers, (2) determine if there is a predom…
Distinct neural-behavioral correspondence within face processing and attention networks for the composite face effect
2022
The composite face effect (CFE) is recognized as a hallmark for holistic face processing, but our knowledge remains sparse about its cognitive and neural loci. Using functional magnetic resonance imaging with independent localizer and complete composite face task, we here investigated its neural-behavioral correspondence within face processing and attention networks. Complementing classical comparisons, we adopted a dimensional reduction approach to explore the core cognitive constructs of the behavioral CFE measurement. Our univariate analyses found an alignment effect in regions associated with both the extended face processing network and attention networks. Further representational simi…
Left-hemisphere dominance in early nociceptive processing in the human parasylvian cortex.
2003
Pain perception comprises sensory and emotional dimensions. While the emotional experience is thought to be represented in the right hemisphere, we here report a left-hemisphere dominance for the early sensory component of pain perception using brain electrical source analysis of laser-evoked potentials. Ten right-handed subjects underwent several series of laser radiant heat stimuli to pairs of parallel lines on the dorsum of the left or right hand. Stimulus location and intensity were randomised independently. The sensory-discriminative aspects of pain were emphasised by asking the subjects to perform either a spatial or an intensity discrimination task and were contrasted with active dis…
Functional changes in brain activity after hypnosis in patients with dental phobia.
2015
Visiting the dentist is often accompanied by apprehension or anxiety. People, who suffer from specific dental phobia (a disproportional fear of dental) procedures show psychological and physiological symptoms which make dental treatments difficult or impossible. For such purposes, hypnosis is often used in dental practice as an alternative for a number of treatments adjuvant or instead of sedation or general anaesthetics, as medication is often associated with risks and side effects. This is the first study to address the effects of a brief dental hypnosis on the fear processing structures of the brain in dental phobics using functional magnetic resonance imaging (fMRI). 12 dental phobics (…