In this work visual functional improvement of amblyopic Long Evans rats treated with tDCS has been assessed
using the “slow angled-descent forepaw grasping” (SLAG) test. This test is based on an innate response that does
not requires any memory-learning component and has been used before for measuring visual function in rodents.
The results obtained show that this procedure is useful to assess monocular but not binocular deficits, as controls
and amblyopic animals showed significant differences during monocular but not during binocular assessment.
On the other hand, parvoalbumin labelling was analysed in three areas of the visual cortex (V1M, V1B and V2L)
before and after tDCS treatment. No changes in labelling were observed after monocular deprivation. However,
tDCS treatment significantly improved vision through the amblyopic eye, and a significant increase of parvoalbumin-positive cells was observed in the three areas, both in the stimulated hemisphere but also in the nonstimulated hemisphere. This effect occurred both in control and amblyopic animals. Thus, tDCS induced changes
are similar in controls and amblyopic animals, although only the last one showed a functional improvement.
