A method is described which has been developed to topographically display the values of spectral EEG analysis from 11 electrodes on each hemisphere and 5 electrodes on the midline. The EEG from 16 channels at a time is multiplexed and sampled at 3.2 kHz. From power spectra averaged every 10 sec for 5 min a few spectral parameters are computed among which are the spectral intensities within the delta, theta, alpha and beta bands. The whole values are then displayed on maps representing lateral views of cerebral hemispheres by means of spectral iso-intensity surfaces with extrapolation of the intermediate points. Different spectral intensities are coded by means of different gray levels. These maps clearly illustrate the topographical distribution of EEG rhythms and their peculiarities related to the side of the head recorded.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/s0370-4475(83)80014-8 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Near-infrared (NIR) phosphor-converted light-emitting diode (pc-LED) has emerged as the most promising NIR light source, highlighting the importance of exploring phosphors with excellent efficiency and sufficient spectral coverage. Herein, a garnet NaCaHfGeO:Cr phosphor with an internal quantum efficiency (IQE) of 79.2% has been developed, which exhibits a relatively long wavelength NIR emission peak at 830 nm and a full width at half maximum (FWHM) of 144 nm.
View Article and Find Full Text PDFComplete 2π cycling of a phase around a phase singularity leads to a rapid phase variation in the nearby zones and forms a sharp local -vector peak. In this paper, the intensity distribution in the spatial domain is transformed into a -vector distribution in the wave vector domain, and we prove that the local -vector peak is generated at the point of minimum light field intensity. The local -vector peak is sharper when the minimum point is closer to the phase singularity.
View Article and Find Full Text PDFQuantitative Analysis of Multi-Elements in a Micron-Sized Single Particle Based on Laser-Induced Breakdown Spectroscopy Signal Enhancement of an Optical Fiber Collimated System.
Anal Chem
January 2025
College of Chemistry and Material Science, Northwest University, Xi'an 710127, China.
With rapid, energy-intensive, and coal-fueled economic growth, global air quality is deteriorating, and particulate matter pollution has emerged as one of the major public health problems worldwide. It is extremely urgent to achieve carbon emission reduction and air pollution prevention and control, aiming at the common problem of weak and unstable signals of characteristic elements in the application of laser-induced breakdown spectroscopy (LIBS) technology for trace element detection. In this study, the influence of the optical fiber collimation signal enhancement method on the LIBS signal was explored.
View Article and Find Full Text PDFHigh-Resolution OCT Reveals Age-Associated Variation in the Region Posterior to the External Limiting Membrane.
Transl Vis Sci Technol
January 2025
New England Eye Center, Tufts Medical Center, Boston, MA, USA.
Purpose: To evaluate visibility of a sub-band posterior to the external limiting membrane (ELM) and assess its age-associated variation.
Methods: In a retrospective cross-sectional study, normal eyes were imaged using a high-resolution spectral-domain optical coherence tomography (SD-OCT) prototype (2.7-µm axial resolution).
Toxicological problems of tattoo removal: characterization of femtosecond laser-induced fragments of Pigment Green 7 and Green Concentrate tattoo ink.
Arch Toxicol
January 2025
STARTNETICS - Department of Chemical Science and Technologies, University of Rome Tor Vergata, Via della Ricerca Scientifica 1, 00133, Rome, Italy.
Femtosecond lasers represent a novel tool for tattoo removal as sources that can be operated at high power, potentially leading to different removal pathways and products. Consequently, the potential toxicity of its application also needs to be evaluated. In this framework, we present a comparative study of Ti:Sapphire femtosecond laser irradiation, as a function of laser power and exposure time, on water dispersions of Pigment Green 7 (PG7) and the green tattoo ink Green Concentrate (GC), which contains PG7 as its coloring agent.
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!