Search results for "processi"
showing 10 items of 9638 documents
Linguistic Bias Modulates Interpretation of Speech via Neural Delta-Band Oscillations.
2017
Language comprehension requires that single words be grouped into syntactic phrases, as words in sentences are too many to memorize individually. In speech, acoustic and syntactic grouping patterns mostly align. However, when ambiguous sentences allow for alternative grouping patterns, comprehenders may form phrases that contradict speech prosody. While delta-band oscillations are known to track prosody, we hypothesized that linguistic grouping bias can modulate the interpretational impact of speech prosody in ambiguous situations, which should surface in delta-band oscillations when grouping patterns chosen by comprehenders differ from those indicated by prosody. In our auditory electroenc…
Effect of electrode location on surface electromyography changes due to eccentric elbow flexor exercise.
2009
Experiments were carried out to determine whether the location of electrodes has an effect on eccentric exercise–induced changes in surface electromyography (sEMG) variables in the biceps brachii muscle. sEMG signals were recorded with a grid of 64 electrodes before and up to 4 days post-exercise. Root mean square (RMS) and mean power frequency (MNF) were calculated for: (1) each channel; (2) as an average of all channels; and (3) as an average of individual channel rows and columns. Mean muscle-fiber conduction velocity (CV) was estimated similarly but was based on double-differential channels. Maximal isometric voluntary torque decreased 21.3 ± 5.6% post-exercise. The average sEMG variabl…
Differences in the topographical distribution of EEG activity during surgical anaesthesia and on emergence from volatile anesthetics.
1994
Computerized processing of a 16 channel EEG allows mapping and display of cortical electrical activity in a useful mode for intraoperative monitoring. We studied the topographical distribution of EEG-activity displayed as spectral maps comparing inhalational anaesthesia with isoflurane or enflurane during surgical anaesthesia and emergence. Two groups of nine patients each were anaesthetized with one of the two regimens. The EEG patterns during steady state end-tidal concentrations of isoflurane (0.7-1.1%) or enflurane (0.8-1.3%) showed highest activity in the frontal and occipital areas. At near awakening the frontal and occipital dominance of delta activity disappeared in both groups and …
Defects in the Human Leukocyte Antigen Class I Antigen Processing Machinery in Head and Neck Squamous Cell Carcinoma: Association with Clinical Outco…
2005
AbstractPurpose: Human leukocyte antigen (HLA) class I antigen defects, which are frequently present in head and neck squamous cell carcinoma (HNSCC) cells may provide the tumor with an escape mechanism from immune surveillance. Scanty information is available about mechanisms underlying HLA class I antigen defects in both lesions and cell lines from HNSCC. In this study, we investigate the role of antigen processing machinery (APM) component abnormalities in the generation of deficient HLA class I surface expression of HNSCC cells.Experimental Design: Using immunohistochemistry, Western blot, and RT-PCR analyses we correlated the expression of the IFN-γ inducible proteasome subunits and of…
Multitasking in aging: ERP correlates of dual-task costs in young versus low, intermediate, and high performing older adults
2018
Abstract With large inter-individual variability, older adults show a decline in cognitive performance in dual-task situations. Differences in attentional processes, working memory, response selection, and general speed of information processing have been discussed as potential sources of this decline and its between-subject variability. In comparison to young subjects (n = 36, mean age: 25 years), we analyzed the performance of a large group of healthy elderly subjects (n = 138, mean age: 70 years) in a conflicting dual-task situation (PRP paradigm). Based on their dual-task costs (DTCs), the older participants were clustered in three groups of high, medium, and low performing elderly. DTC…
Straight gyrus morphology in first-episode schizophrenia-spectrum patients
2010
et al.
Emotional words induce enhanced brain activity in schizophrenic patients with auditory hallucinations.
2005
Neuroimaging studies of emotional response in schizophrenia have mainly used visual (faces) paradigms and shown globally reduced brain activity. None of these studies have used an auditory paradigm. Our principal aim is to evaluate the emotional response of patients with schizophrenia to neutral and emotional words. An auditory emotional paradigm based on the most frequent words heard by psychotic patients with auditory hallucinations was designed. This paradigm was applied to evaluate cerebral activation with functional magnetic resonance imaging (fMRI) in 11 patients with schizophrenia with persistent hallucinations and 10 healthy subjects. We found a clear enhanced activity of the fronta…
Estimation of the dimensionality of sleep-EEG data in schizophrenics
1993
Deterministic chaos could be regarded as a healthy flexibility of the human brain necessary for correct neuronal operations. Several investigations have demonstrated that in healthy subjects the dimensionality of REM sleep is much higher than that of slow wave sleep (SWS). We investigated the sleep-EEG of schizophrenic patients with methods from nonlinear system theory in order to estimate the dynamic properties of CNS. We hypothesized that schizophrenics would reveal alterations of their dynamic EEG features indicating impaired information processing. In 11 schizophrenic patients, the EEG's dimensionality during sleep stages II and REM was reduced. We suggest that such lower dimensional ch…
Motor abnormalities and basal ganglia in first-episode psychosis (FEP)
2020
AbstractBackgroundMotor abnormalities (MAs) are the primary manifestations of schizophrenia. However, the extent to which MAs are related to alterations of subcortical structures remains understudied.MethodsWe aimed to investigate the associations of MAs and basal ganglia abnormalities in first-episode psychosis (FEP) and healthy controls. Magnetic resonance imaging was performed on 48 right-handed FEP and 23 age-, gender-, handedness-, and educational attainment-matched controls, to obtain basal ganglia shape analysis, diffusion tensor imaging techniques (fractional anisotropy and mean diffusivity), and relaxometry (R2*) to estimate iron load. A comprehensive motor battery was applied incl…
Non-compact myocardium assessment by cardiac magnetic resonance: dependence on image analysis method
2018
To compare image analysis methods for the assessment of left ventricle non-compaction from cardiac magnetic resonance (CMR) imaging. CMR images were analyzed in 20 patients and 10 normal subjects. A reference model of the MR signal was introduced and validated based on image data. Non-compact (NC) myocardium size and distribution were assessed by tracing a single, continuous contour delimiting trabeculated region (Jacquier) or by one-by-one selection of trabeculae (Grothoff). The global non-compact/compact (NC/C) ratio, the NC mass, and the segmental NC/C ratio were assessed. Results were compared with the reference model. A significant difference between Grothoff and Jacquier approaches in…