Nanometric resolution magnetic resonance imaging methods for mapping functional activity in neuronal networks

•NV in diamond acts as an atomic size optically detectable spin probe.•The probe combines high magnetic field sensitivity and nanometric resolution.•Non-invasive mapping of functional activity in neuronal networks is one application.•Synapse scale resolution ∼10 nm but circuit scale FoV >1 mm is possible.

This contribution highlights and compares some recent achievements in the use of k-space and real space imaging (scanning probe and wide-filed microscope techniques), when applied to a luminescent color center in diamond, known as nitrogen vacancy (NV) center. These techniques combined with the optically detected magnetic resonance of NV, provide a unique platform to achieve nanometric magnetic resonance imaging (MRI) resolution of nearby nuclear spins (known as nanoMRI), and nanometric NV real space localization.•Atomic size optically detectable spin probe.•High magnetic field sensitivity and nanometric resolution.•Non-invasive mapping of functional activity in neuronal networks.