Objective: When an individual engages in a cognitive task, a multitude of diverse processes are activated in his/her brain and it is reasonable to assume that multiple brain sources are simultaneously active at any one time. Magnetoencephalographic (MEG) data recorded in such circumstances provide a picture of spatial distribution and time course of the sum of the magnetic fields generated by all these sources. Thus, the experimenter faces the challenge of separating the multiple contributions to the total recorded signal before attempting a localization of their sources and studying their functional roles.
Methods: We describe in this paper how independent component analysis of MEG data collected in a word/pseudo-word reading experiment elegantly solves this problem.
Results: Using a few statistical assumptions, independent component analysis resolved simultaneously active brain sources in the right-frontal, left-parietal and left-frontal areas, all showing well defined dipolar field distributions.
Discussion: We describe the characteristics of these contributions and discuss the language-related functional roles that appear to be associated to some of the independent sources. We report in particular on one source, localized near Broca's area, which showed to be affected by reading words but not pseudo-words.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.clinph.2003.09.015 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Access to HIV testing and factors associated among sexual minority women in a metropolitan region of the Brazilian Amazon.
Sci Rep
January 2025
Universidade Federal do Pará, Belém, 66075-110, Brazil.
In Brazil, health policies implemented over the last three decades have enabled rapid testing for HIV to be made available in primary health care services. However, although these policies are national, the implementation of actions is not uniform, as they depend on the local management of local health systems. In this context, the study identified the proportion of women from sexual minorities who had never tested for HIV and the factors associated with access, in a Metropolitan Region of the Brazilian Amazon.
View Article and Find Full Text PDFNutrient control of splice site selection contributes to methionine addiction of cancer.
Mol Metab
January 2025
Department of Biological Chemistry, University of California, Irvine School of Medicine. Electronic address:
Objectives: Many cancer cells depend on exogenous methionine for proliferation, whereas non-tumorigenic cells can divide in media supplemented with the metabolic precursor homocysteine. This phenomenon is known as methionine dependence of cancer or methionine addiction. The underlying mechanisms driving this cancer-specific metabolic addiction are poorly understood.
View Article and Find Full Text PDFElevated glycocalyx shedding components as the early predictors of unfavorable outcomes in patients after cardiac arrest: A single-center observational study.
J Crit Care
January 2025
Department of Emergency Medicine Center, the Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221002, China. Electronic address:
Objective: To assess the association of serum glycocalyx shedding components (Heparan sulfate, HS; Hyaluronic acid, HA; Syndecan-1, Sdc-1) with outcomes after CA.
Methods: Patients who were comatose for >24 h after CA in the intensive care unit (ICU) of the Affiliated Hospital of Xuzhou Medical University from 9/2021 to 04/2023 were enrolled. Serum samples were collected 24 h after CA to measure the concentrations of glycocalyx shedding components.
Mapping conformational landscape in protein folding: Benchmarking dimensionality reduction and clustering techniques on the Trp-Cage mini-protein.
Biophys Chem
January 2025
Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata 700106, India. Electronic address:
Quantitative characterization of protein conformational landscapes is a computationally challenging task due to their high dimensionality and inherent complexity. In this study, we systematically benchmark several widely used dimensionality reduction and clustering methods to analyze the conformational states of the Trp-Cage mini-protein, a model system with well-documented folding dynamics. Dimensionality reduction techniques, including Principal Component Analysis (PCA), Time-lagged Independent Component Analysis (TICA), and Variational Autoencoders (VAE), were employed to project the high-dimensional free energy landscape onto 2D spaces for visualization.
View Article and Find Full Text PDFTelomerase in cancer- ongoing quest and future discoveries.
Mol Biol Rep
January 2025
Department of Integrative Biology, School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu, 632014, India.
Telomerase, constituted by the dynamic duo of telomerase reverse transcriptase (TERT), the catalytic entity, and an integral RNA component (TERC), is predominantly suppressed in differentiated human cells due to postnatal transcriptional repression of the TERT gene. Dysregulation of telomerase significantly contributes to cancer development via telomere-dependent and independent mechanisms. Telomerase activity is often elevated in advanced cancers, with TERT reactivation and upregulation of TERC observed in early tumorigenesis.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!