The purpose of the study is to evaluate the usefulness of a new style of brain imaging for patients with amyotrophic lateral sclerosis (ALS), variants of ALS, and other neurological disorders. This type of brain imaging uses high-resolution, iron-sensitive magnetic resonance imaging (MRI) sequences. The goal is to identify a possible indicator of degeneration (deterioration) of brain cells called the “motor band sign” and understand its clinical significance. The study will compare data obtained from multiple brain MRIs over the course of 1 year with other measurements, such as questionnaires, neurological assessments, and muscle strength assessments. Information from this research could lead to earlier diagnoses of ALS, a better understanding of the disease, and provide a new marker of disease progression in neurodegenerative diseases. Participants will be patients with a neurological disorder of interest or healthy people who are willing to participate as a healthy control (comparison) subject.