Search results for "behavioral"
showing 10 items of 3011 documents
Localization of Brain Networks Engaged by the Sustained Attention to Response Task Provides Quantitative Markers of Executive Impairment in Amyotroph…
2020
Abstract Objective: To identify cortical regions engaged during the sustained attention to response task (SART) and characterize changes in their activity associated with the neurodegenerative condition amyotrophic lateral sclerosis (ALS). Methods: High-density electroencephalography (EEG) was recorded from 33 controls and 23 ALS patients during a SART paradigm. Differences in associated event-related potential peaks were measured for Go and NoGo trials. Sources active during these peaks were localized, and ALS-associated differences were quantified. Results: Go and NoGo N2 and P3 peak sources were localized to the left primary motor cortex, bilateral dorsolateral prefrontal cortex (DLPFC),…
Is that me in the mirror? Depersonalisation modulates tactile mirroring mechanisms
2016
Our sense of self is thought to develop through sensory-motor contingencies provided, not only by observing one's own body, but also by mirroring interactions with others. This suggests that there is a strong link between mirroring mechanisms and the bodily self. The present study tested whether this link is expressed at early, implicit stages of the mirroring process or at later, more cognitive stages. We also provide, to the best of our knowledge, the first demonstration of how inter-individual differences in our sense of bodily self may affect mirroring mechanisms. We used somatosensory event-related potentials (SEPs) to investigate the temporal dynamics of mirroring highly self-related …
Time and spatial attention: Effects of prism adaptation on temporal deficits in brain damaged patients
2011
Growing evidence indicates that the representations of space and time interact in the brain but the exact neural correlates of such interaction remain unknown. Neuroimaging and neuropsychological studies show that processing of temporal information engages a distributed network in the right hemisphere and suggest a link between deficits in spatial attention and deficits in time perception. In the present study we used the procedure of prismatic adaptation (PA) to directionally manipulate spatial attention in order to explore the effect of attentional deviation on time perception in patients with right (RBD) vs. left (LBD) brain damage. In a first experiment, two groups of RBD and LBD patien…
Capturing the musical brain with Lasso: Dynamic decoding of musical features from fMRI data.
2013
We investigated neural correlates of musical feature processing with a decoding approach. To this end, we used a method that combines computational extraction of musical features with regularized multiple regression (LASSO). Optimal model parameters were determined by maximizing the decoding accuracy using a leave-one-out cross-validation scheme. The method was applied to functional magnetic resonance imaging (fMRI) data that were collected using a naturalistic paradigm, in which participants' brain responses were recorded while they were continuously listening to pieces of real music. The dependent variables comprised musical feature time series that were computationally extracted from the…
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…
Early use of phonological codes in deaf readers: An ERP study.
2017
Previous studies suggest that deaf readers use phonological information of words when it is explicitly demanded by the task itself. However, whether phonological encoding is automatic remains controversial. The present experiment examined whether adult congenitally deaf readers show evidence of automatic use of phonological information during visual word recognition. In an ERP masked priming lexical decision experiment, deaf participants responded to target words preceded by a pseudohomophone (koral - CORAL) or an orthographic control prime (toral - CORAL). Responses were faster for the pseudohomophone than for the orthographic control condition. The N250 and N400 amplitudes were reduced fo…
Use of autobilevel ventilation in patients with obstructive sleep apnea: An observational study.
2017
Continuous positive airway pressure (CPAP) is the first-choice treatment for obstructive sleep-disordered breathing. Automatic bilevel ventilation can be used to treat obstructive sleep-disordered breathing when CPAP is ineffective, but clinical experience is still limited. To assess the outcome of titration with CPAP and automatic bilevel ventilation, the charts of 356 outpatients (obstructive sleep apnea, n = 242; chronic obstructive pulmonary disease + obstructive sleep apnea overlap, n = 80; obesity hypoventilation syndrome [OHS], n = 34; 103 females) treated for obstructive sleep-disordered breathing from January 2014 to April 2017 were reviewed. Positive airway pressure titration was …
Segregation of areas related to visual working memory in the prefrontal cortex revealed by rTMS.
2002
The functional organization of working memory (WM) in the human prefrontal cortex remains unclear. Storage and processing functions might be segregated in ventral and dorsal areas of the prefrontal cortex, respectively. If so, storage functions might be spared, irrespective of informational domain, following damage or dysfunction in dorsolateral areas. Alternatively, WM and prefrontal function in general might be segregated according to informational domains (e.g. spatial versus object-based information). In the present study we used repetitive transcranial magnetic stimulation (rTMS) to directly test these competing hypotheses. We applied rTMS to transiently and selectively disrupt the fun…
Chronometry of parietal and prefrontal activations in verbal working memory revealed by transcranial magnetic stimulation.
2003
We explored the temporal dynamics of parietal and prefrontal cortex involvement in verbal working memory employing single-pulse transcranial magnetic stimulation (TMS). In six healthy volunteers the left or right inferior parietal and prefrontal cortex was stimulated with the aid of a frameless stereotactic system. TMS was applied at 10 different time points 140-500 ms into the delay period of a two-back verbal working memory task. A choice reaction task was used as a control task. Interference with task accuracy was induced by TMS earlier in the parietal cortex than in the prefrontal cortex and earlier over the right than the left hemisphere. This suggests a propagation of information flow…
The influence of rTMS over prefrontal and motor areas in a morphological task: grammatical vs. semantic effects
2008
We investigated the differential role of two frontal regions in the processing of grammatical and semantic knowledge. Given the documented specificity of the prefrontal cortex for the grammatical class of verbs, and of the primary motor cortex for the semantic class of action words, we sought to investigate whether the prefrontal cortex is also sensitive to semantic effects, and whether the motor cortex is also sensitive to grammatical class effects. We used repetitive transcranial magnetic stimulation (rTMS) to suppress the excitability of a portion of left prefontal cortex (first experiment) and of the motor area (second experiment). In the first experiment we found that rTMS applied to t…