Brain vibration signal extraction and characterization

The heart beat drives blood bilaterally up into the brain through the carotid arteries and the asymmetric blood flow sets the brain into a pulsing motion. This brain’s pulse can be altered in a predictable way by brain disorders or abnormalities. These abnormalities may be vascular such as ischemia, aneurisms or vasospasms or they can be structural such as concussion or dementia. The brain’s pulse impacts the skull and can be measured with highly sensitive accelerometers distributed around the head. This is why Brainlab implemented a simple headset involving accelerometers that are pressed against the head. In this way vibration signals can be obtained. However the signals are highly corrupted by noise and by other dynamics that are also related with the heart. Therefore artefact belonging to seismocardiography, respiration and body motion strongly hide the vibration from the brain. The main objective of this project is to extract the part of the signal that is directly related with the brain motion and to correlate this movement with brain disorders. For that advanced signal processing algorithms based on modal and wavelet analysis are designed and implemented in order to extract a signal signature related with the dynamical movement of the brain.