On the detection of denrite activity using MRI

Abstract

The currents associated with neural activity generate their own magnetic fields which potentially cause a measurable phase change in a magnetic resonance (MR) signal. The feasibility of directly measuring neural currents via magnetic resonance imaging (MRI) is still under debate. If direct imaging were possible, there would be immediate benefits for neurosurgeons, doctors studying degenerative diseases of the brain, neuroscientists, and others. In this thesis, individually dendrites are modeled as magnetic current dipoles on a variable lattice structure in order to calculate the magnetic fields and phase shifts generated by active neural tissue. The results show that the field produced by a dense collection of simultaneously active dendrites may be just detectable under the most ideal circumstances, but in almost every realistic case the field cannot be detected using current MRI technology.