An electrical interaction with the central nervous system (CNS) to achieve therapeutic effects, can take place, depending on the problem, in both directions, i.e., 'put in' or 'read out'. An example of a reading out electrical interaction is the Brain Machine Interface (BMI), also known as brain computer interface (BCI), which decodes the measured brain activity in order to derive intentions or commands that allow patients with paralysis after stroke or spinal cord injury to use equipment or to control prostheses. While currently available BMI systems allow multi-channel non-invasive and invasive EEG signal detection, a lack in insufficient electrode quality and pre-processing and classification algorithms cause no reliable decoding and execution of complex motoric commands.
BMI are subject of basic research in Magdeburg, in which measurement techniques, classification methods and stimulation paradigms are developed. An approach that can decode the brain activity with just one EEG electrode which is placed in the outer ear canal has been developed. This allows integrating a simple BMI into a headphone of a multimedia device. The electrode grids commercially offered for more complex tasks to derive the activity directly on the cortex (Electrocorticography (ECoG)) are with respect to its recoverable signal-to-noise ratio (SNR) and spatial resolution is not sufficient. As an improvement, a method has been developed, that forms an appropriate laser-based structure of miniaturized interconnects and electrodes made of a platinum film, which is inserted and contacted through a microsystem process in a biocompatible grid. With respect to the signal interpretation classification concepts have been adapted to classify individual trials much higher then coincidence rate in both invasive (ECoG) and non-invasive signals (MEG, EEG). A modification in the direction of real-time application is intended, but requires appropriate equipment modifications.
Eröffnung
