Recording of brain activity across spatial scales

- Brain activity is highly structured within local and distributed circuits.
- Understanding brain function requires simultaneous recording across spatial scales.
- Multi-electrode arrays allow targeted recording from local and distributed circuits.
- Wide sampling allows identification of distributed networks and topographic mapping.
- Targeted dense recording allows integration of local and distributed dynamics.

Brain activity reveals exquisite coordination across spatial scales, from local microcircuits to brain-wide networks. Understanding how the brain represents, transforms and communicates information requires simultaneous recordings from distributed nodes of whole brain networks with single-cell resolution. Realizing multi-site recordings from communicating populations is hampered by the need to isolate clusters of interacting cells, often on a day-to-day basis. Chronic implantation of multi-electrode arrays allows long-term tracking of activity. Lithography on thin films provides a means to produce arrays of variable resolution, a high degree of flexibility, and minimal tissue displacement. Sequential application of surface arrays to monitor activity across brain-wide networks and subsequent implantation of laminar arrays to target specific populations enables continual refinement of spatial scale while maintaining coverage.