Search results for " Direct"
showing 10 items of 943 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…
"…The times they aren't a-changin'…" rTMS does not affect basic mechanisms of temporal discrimination: a pilot study with ERPs.
2014
In time processing, the role of different cortical areas is still under investigation. Event-related potentials (ERPs) represent valuable indices of neural timing mechanisms in the millisecond-to-second domain. We used an interference approach by repetitive TMS (rTMS) on ERPs and behavioral performance to investigate the role of different cortical areas in processing basic temporal information. Ten healthy volunteers were requested to decide whether time intervals between two tones (S1-S2, probe interval) were shorter (800 ms), equal to, or longer (1200 ms) than a previously listened 1000-ms interval (target interval) and press different buttons accordingly. This task was performed at the b…
Modulating memory performance in healthy subjects with Trancranial Direct Current Stimulation over the right dorsolateral prefrontal cortex
2015
Objective: The role of the Dorsolateral Prefrontal Cortex (DLPFC) in recognition memory has been well documented in lesion, neuroimaging and repetitive Transcranial Magnetic Stimulation (rTMS) studies. The aim of the present study was to investigate the effects of transcranial Direct Current Stimulation (tDCS) over the left and the right DLPFC during the delay interval of a non-verbal recognition memory task. Method: 36 right-handed young healthy subjects participated in the study. The experimental task was an Italian version of Recognition Memory Test for unknown faces. Study included two experiments: in a first experiment, each subject underwent one session of sham tDCS and one session of…
TRANSCRANIAL DIRECT CURRENT STIMULATION ENHANCES SUCKING OF A LIQUID BOLUS IN HEALTHY HUMANS
2014
Abstract Background Transcranial direct current stimulation (tDCS) is a non-invasive technique used for modulating cortical excitability in vivo in humans. Here we evaluated the effect of tDCS on behavioral and electrophysiological aspects of physiological sucking and swallowing. Methods Twelve healthy subjects underwent three tDCS sessions (anodal, cathodal and sham stimulation) on separate days in a double-blind randomized order. The active electrode was placed over the right swallowing motor cortex. Repeated sucking and swallowing acts were performed at baseline and at 15 and 60 min after each tDCS session and the mean liquid bolus volume ingested at each time point was measured. We also…
Effects of barbell back squat stance width on sagittal and frontal hip and knee kinetics
2018
Different stance widths are commonly utilized when completing the barbell back squat during athletic general preparedness training. Width manipulation is thought to influence sagittal plane stimuli to the hip and knee extensors, the primary extensor musculature in the squat. However, how width manipulation affects frontal plane stimuli is less understood. Knowledge of hip and knee net joint moments (NJM) could improve exercise selection when aiming to improve sport-specific performance and prevent injuries. Fourteen adult amateur rugby athletes were recruited for this study. After a familiarization period, participants performed wide- (WIDE, 1.5× greater trochanter width) and narrow-stance …
Mentalizing eye contact with a face on a video : Gaze direction does not influence autonomic arousal
2018
Recent research has revealed enhanced autonomic and subjective responses to eye contact only when perceiving another live person. However, these enhanced responses to eye contact are abolished if the viewer believes that the other person is not able to look back at the viewer. We purported to investigate whether this "genuine" eye contact effect can be reproduced with pre-recorded videos of stimulus persons. Autonomic responses, gaze behavior, and subjective self-assessments were measured while participants viewed pre-recorded video persons with direct or averted gaze, imagined that the video person was real, and mentalized that the person could see them or not. Pre-recorded videos did not …
Testing Frequency-Domain Causality in Multivariate Time Series
2010
We introduce a new hypothesis-testing framework, based on surrogate data generation, to assess in the frequency domain, the concept of causality among multivariate (MV) time series. The approach extends the traditional Fourier transform (FT) method for generating surrogate data in a MV process and adapts it to the specific issue of causality. It generates causal FT (CFT) surrogates with FT modulus taken from the original series, and FT phase taken from a set of series with causal interactions set to zero over the direction of interest and preserved over all other directions. Two different zero-setting procedures, acting on the parameters of a MV autoregressive (MVAR) model fitted on the ori…
Six novel mutations of the LDL receptor gene in FH kindred of Sicilian and Paraguayan descent
2006
Familial hypercholesterolemia (FH) is an autosomal dominant inherited disease caused by mutations in the gene coding for the low density lipoprotein receptor (LDL-R). It is characterized by a high concentration of low density lipoprotein (LDL), which frequently gives rise to premature coronary artery disease. We studied the probands of five FH Sicilian families with 'definite' FH and one proband of Paraguayan descent with homozygous FH who has been treated with an effective living-donor liver transplantation. In order to seek the molecular defect in these six families, we used direct sequencing to define the molecular defects of the LDL-R gene responsible for the disease. We described three…
AEROgui: A graphical user interface for the optical properties of aerosols
2014
Atmospheric aerosols have an uncertain effect on climate and serious impacts on human health. The uncertainty in the aerosols' role on climate has several sources. First, aerosols have great spatial and temporal variability. The spatial variability arises from the fact that aerosols emitted in a certain place can travel thousands of kilometers, swept by the winds to modify the destination region's climate. The spatial variability also means that aerosols are inhomogeneously distributed in the vertical direction, which can lead to a differential effect on the energy balance depending on the aerosols' altitude. On the other hand, aerosols experience physical and chemical transformations in th…