Figure 1.

Scheme of the experimental design. Two independent cohorts of mice were trained daily in the visual water task (VWT) until reaching binocular visual acuity (VA) based on established protocols (Prusky et al., 2000b, 2004). At the day of standard VA assessment, the two groups were also tested in the virtual-reality optomotor (OPT) system (optomotry) to determine the spatial frequency threshold of the OPT response (standard OPT threshold). One of the cohorts then obtained monocular deprivation (MD). Both cohorts were continued to be trained in the VWT. The monocular VA and OPT threshold of the VWT/MD group (during MD) was again determined after reaching the criterion (see Materials and Methods). In about half of the mice of the VWT/MD group, the MD was reopened and mice were continued to be trained daily in the VWT (VWT/MD-reopening). The binocular long-term VA and OPT threshold of both the VWT/no-MD and VWT/MD-reopening group was again tested after a comparable training time (see Materials and Methods). Instead of reopening the MD, optical imaging of intrinsic signals (OI) was performed with the other half of the deprived group (VWT/MD-OI). For comparison, a cohort of mice that had been deprived for a comparably long time but not VWT-trained was imaged (SC/MD-OI). As a control for the long-term trained VWT/MD group, we used the VWT/no-MD group after finishing the VWT (VWT/no-MD-OI). Likewise, we also tested an age-matched nondeprived, SC-housed cohort (SC/no-MD-OI).