In the first year of the award, we performed a comprehensive analysis of the anatomical and in vivo electrophysiological responses of V1 to central visual system TBI. These studies were published (Frankowski, Foik, et al., 2021) and form the basis from which we will test an interneuron cell therapy. Toward this goal, we performed initial cell transplants into V1 of control animals and 1 week after TBI. Transplanted cells display the expected characteristics, and we are currently evaluating their electrophysiological incorporation into the injured brain. During the next two years, we plan to continue progress toward developing interneuron cell therapy for V1 TBI. This work will provide new information about the plasticity of the injured visual system and advance our long-term goal of developing an interneuron cell therapy for TBI.