A Study of LY3857210 in Healthy Participants

Inclusion Criteria: * Overtly healthy male or female participants as determined by medical evaluation * Have body weight ≥ 45 kilograms (kg) and body mass index (BMI) within the range 18.5 to 32.0 kilograms per square meter (kg/m²) (inclusive) * Are males and in agreement to follow contraceptive requirements, or women of non-child-bearing potential Exclusion Criteria: * Have contraindications to undergoing magnetic resonance imaging (MRI) examination including but not limited to implants such as implanted cardiac pacemakers or defibrillators, insulin pumps, cochlear implants, metallic ocular foreign body, implanted neural stimulators, CNS aneurysm clips, and other medical implants that have not been certified for head MRI * Have clinically significant findings on the screening MRI scan, as judged by the investigator * Suffer from claustrophobia and would be unable to tolerate the confined spaces of MRI or PET camera