These are all non-visual regions. In one animal (animal no. 3), the posterior cingulate cortex was also removed from the bend of the splenial sulcus posteriorly to ~ A13 anteriorly. Inclusion of this cortex in the lesion did not change the effect of
lesion or the pattern of recovery, and we conclude that this cortex is probably unable to compensate for the effects of the lesion. A secondary evaluation was made by microscopic examination of the thalamus, which showed widespread gliosis and volumetric reduction in regions of the visual thalamus connected with the cerebrum. The laminae of the ipsilesional dorsal lateral geniculate nucleus had been reduced in volume and http://www.selleckchem.com/products/AZD6244.html were filled with small Topoisomerase inhibitor cells consistent with glia. Large cells characteristic of geniculate relay neurons were not observed. The lateral posterior and pulvinar nuclei were similarly devoid of large neurons and showed a decrease in volume that altered the morphology of the thalamus. Overall, no regions of sparing were identified in any animals after primary or secondary analysis, and we concluded that the lesions were complete. All animals exhibited perfect (100%) performance in the standard moving perimetry task prior to lesion. After lesion, performance to targets presented in the contralesional
visual hemifield fell to zero (Fig. 3). Performance to targets in the ipsilesional visual hemifield was
unaltered by lesion. Adenosine Animals were evaluated 2 months after the lesion to account for any spontaneous recovery of function to contralesional targets; none was observed. Control animals did not show any recovery of function for any task for 2 years after lesion (data not shown). Two months after lesion, a regimen of cathodal tDCS began. Stimulation was delivered to the intact hemisphere for 20 min per day for 5 days a week, and was centered on the posterior middle suprasylvian area. The stimulation strength was set at 2 mA and the size of the electrodes was 4 cm2 (2 × 2 cm), producing a current density of 0.5 mA/cm2. Stimulation was performed for 14 consecutive weeks. Stimulation had a beneficial effect on contralesional performance in the standard perimetry task in three out of four animals. The fourth animal did not show recovery of any kind and was not considered in any group analysis. An anova revealed a significant effect of time on performance to contralesional, but not ipsilesional, targets (contralesional, F17,36 = 7.610, P < 0.0001; ipsilesional, F17,36 = 0.5210, P = 0.9241). Tukey’s HSD post hoc tests between the pre-tDCS time point and subsequent points showed a significant improvement in contralesional performance at the week 10, 11, 12, 13 and 14 time points, and for the post-tDCS time points (assessed at post-tDCS days 5 and 11).