Search results for " brain"
showing 10 items of 985 documents
Neglect-like effects induced by tDCS modulation of posterior parietal cortices in healthy subjects
2011
Background Repetitive transcranial magnetic stimulation (rTMS) over right posterior parietal cortex was shown to induce interference on visuospatial perception in healthy subjects. Transcranial direct current stimulation (tDCS) is another noninvasive brain stimulation technique that works modulating cortical activity. It is applied through easy to use, noncostly, and portable devices. Objective/Hypothesis The aim of the current study was to investigate if the novel approach of “dual” stimulation over parietal cortices compared with the unilateral (right) cathodal one is able to induce greater and/or longer-lasting neglect-like effects in normal subjects performing a computerized visuospatia…
Neural correlates of disturbed perception of verticality.
2012
Objective: Perception of verticality can be perturbed after cortical stroke. However, a relationship between lesion location and pathologic perception of verticality is still a matter of debate since previous studies revealed contradictory results. Thus, the aim of the current study was to test whether specific cortical lesions were associated with tilts of subjective visual vertical (SVV) and to determine the critical brain areas that cause such tilts in the case of a lesion. Methods: SVV was systematically studied in 54 patients (22 patients with left-sided and 32 patients with right-sided lesions) with acute unilateral strokes, analyzed by modern voxel-wise lesion-behavior mapping techni…
The value of N-terminal fragment of brain natriuretic peptide and tissue inhibitor of metalloproteinase-1 levels as predictors of cardiovascular outc…
2008
Aims We sought to determine the association between two major biomarkers, the inactive N-terminal fragment of brain natriuretic peptide (NT-proBNP) and tissue inhibitor of metalloproteinase-1 (TIMP-1) and long-term cardiovascular outcomes in a cohort of subjects who had a myocardial infarction or unstable angina 3–36 months previously. Methods and results Plasma NT-proBNP and TIMP-1 were measured in a nested case control study of 250 randomly matched subject pairs enrolled in the long-term intervention with pravastatin in ischaemic disease (LIPID) and LIPID extended follow-up studies. Cases ( n = 250) were defined as those who had a cardiovascular death, non-fatal myocardial infarction or s…
Prognostic value of N-terminal pro-brain natriuretic peptide in elderly people with acute myocardial infarction: prospective observational study
2009
Objective To examine the influence of age on the predictive value of N-terminal pro-brain natriuretic (NT-proBNP) peptide assay in acute myocardial infarction. Design Prospective observational study. Setting All intensive care units in one French region. Participants 3291 consecutive patients admitted for an acute myocardial infarction, from the RICO survey (a French regional survey for acute myocardial infarction). Main outcome measure Cardiovascular death at 1 year. Results Among the 3291 participants, mean age was 68 (SD 14) years and 2356 (72%) were men. In the study population, the median NT-proBNP concentration was 1053 (interquartile range 300-3472) pg/ml. Median values for age quart…
Covariation of spectral and nonlinear EEG measures with alpha biofeedback.
2002
Item does not contain fulltext This study investigated how different spectral and nonlinear EEG measures covaried with alpha power during auditory alpha biofeedback training, performed by 13 healthy subjects. We found a significant positive correlation of alpha power with the largest Lyapunov-exponent, pointing to an increased dynamical instability of the EEG accompanying alpha enhancement. Alpha power amplification, moreover, was significantly correlated with a decrease of spectral entropy within the alpha range. This outcome reflects a sharpening of the alpha peak during biofeedback training. The fact that the sharpening effect clearly preceded the increase of alpha amplitude could be exp…
Life goals after brain injury in the light of the dual process approach: empirical evidence and implications for neuropsychological rehabilitation.
2011
Sequelae of acquired brain injury endanger the realisation of important life-goals. Discrepancies arise between the importance attached to a goal and the success in realising it. This study investigates goal discrepancies and their influence on patients' subjective well-being (SWB) in different rehabilitation stages. Life-goals, SWB and daily functioning were assessed in 130 neurological inpatients and 42 outpatients by self-report questionnaires. Both patient groups reported greater discrepancies between importance and success of life-goals than a normative sample of healthy controls. In multiple regression modelling, goal discrepancy predicted SWB in the inpatient sample even when control…
Sex differences in interhemispheric communication during face identity encoding: Evidence from ERPs
2013
Sex-related hemispheric lateralization and interhemispheric transmission times (IHTTs) were examined in twenty-four participants at the level of the first visual ERP components (P1 and N170) during face identity encoding in a divided visual-field paradigm. While no lateralization-related and sex-related differences were reflected in the P1 characteristics, these two factors modulated the N170. Indeed, N170 amplitudes indicated a right hemisphere (RH) dominance in men (and a more bilateral functioning in women). N170 latencies and the derived IHTTs confirmed the RH advantage in men but showed the reverse asymmetry in women. Altogether, the results of this study suggest a clear asymmetry in m…
Effects of post-extinction l-DOPA administration on the spontaneous recovery and reinstatement of fear in a human fMRI study
2015
Relapse is a pertinent problem in the treatment of anxiety disorders. In the laboratory, relapse is modeled as return of conditioned fear responses after successful fear extinction and is explained by insufficient retrieval and/or expression of the fear-inhibitory extinction memory that is generated during extinction learning. We have shown in mice and humans that return of fear can be prevented by administration of a single dose of the dopamine precursor l-3,4-dihydroxyphenylalanine (l-DOPA) immediately after extinction. In mice, this effect could be attributed to an enhancement of extinction memory consolidation. In our human study, we could not exclude that l-DOPA might have acted by int…
Lateralized effects of self-induced sadness and happiness on corticospinal excitability.
1997
We studied the changes in excitability of the corticospinal projection evoked by self-induced sad and happy thoughts. Corticospinal excitability was probed using focal, single-pulse transcranial magnetic stimulation (TMS) applied to the optimal scalp position for evoking motor potentials in the contralateral first dorsal interosseus muscle. Fourteen right-handed subjects were studied while counting mentally, thinking sad thoughts, or thinking happy thoughts. In each of these three conditions TMS was applied in each subject randomly, 20 times to the right and 20 times to the left hemisphere. Sad thoughts resulted in a significant facilitation of the motor potentials evoked by left-hemispheri…
Living with acquired brain injury: Self-concept as mediating variable in the adjustment process
2010
Sequelae of acquired brain injury (ABI) require adjustment processes in which survivors must strive to regain subjective well-being (SWB) in the face of chronic impairment. The current study investigates whether the self-concept of achievement mediates this process. Thirty-five post-acute patients with ABI were assessed neuropsychologically for performance in memory, attention, concept formation and reasoning. Data concerning subjective complaints in applied cognition, self-concept, and SWB were collected. Patients rated their self-concept more negatively compared to a normative sample. Effects of subjective complaints in applied cognition on SWB were mediated by the self-concept of achieve…