Sign up for email alert when new content gets added: Sign up
Visual performance of animals is usually characterized by the thresholds for visual acuity and contrast sensitivity. However, established behavioral and electrophysiological methods are often time consuming or require invasive surgeries. Here we describe a novel procedure to determine visual abilities in mice, using periodic optical imaging of intrinsic signals. This is a relatively fast and non-invasive procedure to obtain reliable topographic maps in sensory cortices. First, we determined the best anesthetic conditions to obtain primary visual cortex [V1] maps with high amplitudes and good quality. After this, we demonstrate that measuring V1 activity evoked by visual stimulation with sine wave gratings of different contrasts and spatial frequencies provides reliable data of V1 contrast and spatial frequency tuning. We then compared the optical imaging data with values of contrast sensitivity and visual acuity obtained using a well-established behavioral test, the visual water task [VWT]. We found a close correspondence between these different approaches. Finally, we first trained a group of mice in the VWT and subsequently used the same animals in optical imaging experiments. Strikingly, we found that our measurements of visual perception in the behavioral and physiological experiments were practically identical, also at the level of individual animals. Taken together, our results clearly demonstrate that intrinsic signal imaging enables determination of visual abilities in a fast and simple manner.
