Fig. 1.

Animal preparation and imaging timeline. (a) Cross-sectional schematic of window preparation above angled (20 deg to 30 deg relative to the brain surface) electrode insertion, which allows long-term visualization of vessels and neurons. The entire preparation is sealed permanently with dental cement. HB: head-bar. Inset shows 16-channel electrode diagram. (b) Timeline of chronic imaging and electrophysiological recording following window surgery and electrode implantation on day 0. For the first week, animals were imaged on day 1 (allowing a 24-h recovery following surgery) and day 4. Beginning with day 8, animals were imaged weekly for 6 months, then monthly from month 6 to the end of in vivo experiments. (c) Imaging and recording duration for each electrode-implanted and window-only control animal reported in this study. Of the 12 animals used for longitudinal imaging and electrophysiology (Ephys) recording, 10 were imaged for over 6 months ($n_{\text{electrode}}=5$, $n_{\text{window-only}}=5$) and four were imaged for over 1 year ($n_{\text{electrode}}=2$, $n_{\text{window-only}}=2$).