Open Source
a) Real-time phase analysis
MATLAB software for estimating the phase of a physiological signal with an oscillatory component (e.g. Gamma activity) in real-time: In an on-going experiment, physiological signals are only known up to the last sample acquired by a recording device. This makes estimation of the current phase of the oscillatory component difficult, since normal phase estimation methods require knowing how the signal will evolve in the future (e.g. Wavelet transform). The method provided here makes use of autoregressive (AR) modelling to obtain a phase estimate which is as accurate as possible up to the latest recorded sample.
Author of the toolbox: Dr. Dmitriy Lisitsyn. This work was supported by the Deutsche Forschungsgemeinschaft priority program SPP 1665 'Resolving and manipulating neuronal networks in the mammalian brain - from correlative to causal analysis' (ER 324/3-2).
b) Fully-Wireless Sub-Cranial Neuro-Implant for Measuring Electrocorticography Signals
Implantable neuronal interfaces to the brain are an important keystone for future medical applications. However, entering this field of research is difficult since such an implant requires components from many different areas of technology. Since the complete avoidance of wires is important due to the risk of infections and other long-term problems, means for wireless transmitting data and energy are a necessity which adds to the requirements. In recent literature many high-tech components for such implants are presented with remarkable properties. However, these components are typically not freely available for your system. Every group needs to re-develop their own solution. This raises the question if it is possible to create a reusable design for an implant and its external base-station, such that it allows other groups to use it as a starting point. In this article we try to answer this question by presenting a design based exclusively on commercial off-the-shelf components and studying the properties of the resulting system. Following this idea, we present a fully wireless neuronal implant for simultaneously measuring electrocorticography signals at 128 locations from the surface of the brain. All design files are available as open source.
This work were supported in part by Bundesministerium fuer Bildung und Forschung, Grant 01 EZ 0867 (Innovationswettbewerb Medizintechnik) and Grant 01 GQ 1106 (Bernstein Award Udo Ernst) as well as Research-Focus Neurotechnology University of Bremen, and the Creative Unit I-See 'The artificial eye: Chronic wireless interface to the visual cortex' at the University of Bremen. Also this work was supported by the Deutsche Forschungsgemeinschaft priority program SPP 1665 'Resolving and manipulating neuronal networks in the mammalian brain - from correlative to causal analysis' (LA 1471/11-1).