Electrophysiological Source Imaging of Brain Networks Perturbed by Low-Intensity Transcranial Focused Ultrasound

Focused Ultrasound Help Realize High Spatiotemporal Brain Imaging?-A Concept on Acousto-Electrophysiological Neuroimaging

We present a concept for integrating focused ultrasound (FUS) with electrophysiological neuroimaging, in order to achieve high spatiotemporal resolution brain imaging. This approach, which we are tentatively calling acousto-electrophysiological neuroimaging, leverages on the spatial focality and noninvasiveness of FUS and may potentially lead to a noninvasive human brain imaging modality with high resolution in both space and time domains. By the use of modulated FUS, spatial selectivity can be accomplished for high-resolution electrophysiological neuroimaging. Frequency shifting in resulting magnetic signals (using modulated FUS) may potentially open the door for a room temperature magnetoencephalography device.

Combined EMD-sLORETA Analysis of EEG Data Collected during a Contour Integration Task

Lately, Ensemble Empirical Mode Decomposition (EEMD) techniques receive growing interest in biomedical data analysis. Event-Related Modes (ERMs) represent features extracted by an EEMD from electroencephalographic (EEG) recordings. We present a new approach for source localization of EEG data based on combining ERMs with inverse models. As the first step, 64 channel EEG recordings are pooled according to six brain areas and decomposed, by applying an EEMD, into their underlying ERMs. Then, based upon the problem at hand, the most closely related ERM, in terms of frequency and amplitude, is combined with inverse modeling techniques for source localization. More specifically, the standardized low resolution brain electromagnetic tomography (sLORETA) procedure is employed in this work. Accuracy and robustness of the results indicate that this approach deems highly promising in source localization techniques for EEG data.