6 research outputs found
Feasibility and resolution limits of opto-magnetic imaging of neural network activity in brain slices using color centers in diamond
We suggest a novel approach for wide-field imaging of the neural network
dynamics of brain slices that uses highly sensitivity magnetometry based
on nitrogen-vacancy (NV) centers in diamond. Invitro recordings in brain
slices is a proven method for the characterization of electrical neural
activity and has strongly contributed to our understanding of the
mechanisms that govern neural information processing. However, this
traditional approach only acquires signals from a few positions, which
severely limits its ability to characterize the dynamics of the
underlying neural networks. We suggest to extend its scope using NV
magnetometry-based imaging of the neural magnetic fields across the
slice. Employing comprehensive computational simulations and theoretical
analyses, we determine the spatiotemporal characteristics of the neural
fields and the required key performance parameters of an NV
magnetometry-based imaging setup. We investigate how the technical
parameters determine the achievable spatial resolution for an optimal 2D
reconstruction of neural currents from the measured field distributions.
Finally, we compare the imaging of neural slice activity with that of a
single planar pyramidal cell. Our results suggest that imaging of slice
activity will be possible with the upcoming generation of NV magnetic
field sensors, while single-shot imaging of planar cell activity remains
challenging
Precision temperature sensing in the presence of magnetic field noise and vice-versa using nitrogen-vacancy centers in diamond
We demonstrate a technique for precision sensing of temperature or the
magnetic field by simultaneously driving two hyperfine transitions involving
distinct electronic states of the nitrogen-vacancy center in diamond. Frequency
modulation of both driving fields is used with either the same or opposite
phase, resulting in the immunity to fluctuations in either the magnetic field
or the temperature, respectively. In this way, a sensitivity of 1.4 nT
Hz or 430 K Hz is demonstrated. The presented technique
only requires a single frequency demodulator and enables the use of
phase-sensitive camera imaging sensors. A simple extension of the method
utilizing two demodulators allows for simultaneous, independent, and
high-bandwidth monitoring of both the magnetic field and temperature.Comment: 5 pages, 4 figure