Amyotrophic Lateral Sclerosis, also known as ALS, is a progressive neurodegenerative disease characterized by the death of both upper and lower motor neurons. This selective degeneration of these discrete cell types, caused by mutations expressed ubiquitously, is what causes research behind ALS to be incredibly difficult. In this study, we aim to use Adeno Associated Virus engineered for retrograde labeling (AAV-retro) to quantify cell density in both vulnerable and invulnerable populations in layer 5b of the motor cortex. When analyzed, it was revealed that on the 90th postnatal day of ALS, SOD mice showed a 4.12% decrease in cell density compared to that wild-type mice. Although this decrease may not seem significant, it begins to lay the framework for a more in-depth disease timeline for the SOD-mouse model in ALS.