Influence of anisotropic conductivity on EEG source reconstruction: investigations in a rabbit model.

The aim of our work was to quantify the influence of white matter anisotropic conductivity information on electroencephalography (EEG) source reconstruction. We performed this quantification in a rabbit head using both simulations and source localization based on invasive measurements. In vivo anisotropic (tensorial) conductivity information was obtained from magnetic resonance diffusion tensor imaging and included into a high-resolution finite-element model.

Fetal MCG and fetal MEG measurements with a 3-channel SQUID system.

Since the high costs of common large array SQUID system may hinder widespread application of fetal magnetoencephalography (fMEG) and magnetocardiography (fMCG), we intended to investigate a small non-commercial 3-channel SQUID system. The system comprises 3 axial first order gradiometers with 7 cm base length, 2 cm diameter and 2x2 windings of niobium wire, dc-SQUIDs (UJ-111), and current locked mode SQUID electronics that form an equal length triangle (22.5 mm).

Inhomogeneous propagation of cortical spreading depression-detection by electro- and magnetoencephalography in rats.

Spreading depression (SD) propagates in cortical regions that are different in their morphological and functional characteristics. We tested whether the propagation pattern of spreading depression was different between parts of the cortex. In six adult rats, we recorded the ECoG by a 4 x 4 electrode array that covered parts of the frontal, parietal cortex and the cingulate cortex.

Effects of discotheque music on audiometric results and central acoustic evoked neuromagnetic responses.

Audiograms and auditory evoked magnetic fields (AEFs) were observed in young male and female adults at different ages before and after being exposed to discotheque music for 4 hours. Sound pressure levels (SPLs) ranged from 95 dB (SPL) up to 130 dB (SPL). After exposure, subjects had temporary threshold shifts up to 20-25 dB, which almost disappeared after 2 hours.

Sensitive magnetic sensors without cooling in biomedical engineering.

Magnetic field sensors are used in various fields of technology. In the past few years a large variety of magnetic field sensors has been established and the performance of these sensors has been improved enormously. In this review article all recent developments in the area of sensitive magnetic field sensory analysis (resolution better than 1 nT) are presented and examined regarding their parameters.