Current techniques of neuroimaging, including electrical devices, are either
of low spatiotemporal resolution or invasive, impeding multiscale monitoring of
brain activity at both single cell and network levels. Overcoming this issue is
of great importance to assess brain's computational ability and for
neurorehabilitation projects that require real-time monitoring of neurons and
concomitant networks activities. Currently, that information could be extracted
from functional MRI when combined with mathematical models. Novel methods
enabling quantitative and long-lasting recording at both single cell and
network levels will allow to correlate the MRI data with intracortical activity
at single cell level, and to refine those models. Here, we report the
fabrication and validation of ultra-thin, optically transparent and flexible
intracortical microelectrode arrays for combining extracellular multi-unit and
fMRI recordings. The sensing devices are compatible with large-scale
manufacturing, and demonstrate both fMRI transparency at 4.7 T, and high
electrical performance, and thus appears as a promising candidate for
simultaneous multiscale neurodynamic measurements