Inclusion Criteria:
* Age 55-90 years old
* Self-identifying as generally medically healthy
* Able to read, write and speak English
* Able to provide informed consent and attend all testing sessions
* Willing to undergo the experimental pain paradigm, if selected
Exclusion Criteria:
* Resting heart rate \< 50 or \> 100 bpm
* Resting blood pressure \< 90/60 or \> 165/95
* Any history or current mental health condition, learning/developmental disability or cognitive impairment, including severe untreated ADD/ADHD, severe untreated anxiety, severe untreated depression, autism spectrum disorder, insomnia, mild cognitive impairment, etc. (Mild to moderate treated ADD/ADHD, anxiety, and/or depression are allowed.)
* Score on the Montreal Cognitive Assessment (MoCA) \<23
* Score on the Generalized Anxiety Disorder-7 Scale ≥ 10
* Score on the Patient Health Questionnaire-2 ≥ 2 and score on the Patient Health Questionnaire-9 ≥ 10
* Any current (within last 3 month) or chronic medical conditions, including any musculoskeletal, cardiovascular, pulmonary, metabolic, psychiatric or neurological diagnosis that affects activities of daily living or would confound testing or place the subject at risk by participating, such as a significant cardiovascular condition or event (e.g., heart attack \< 3 months ago, uncontrolled atrial fibrillation, uncontrolled angina, congestive heart failure, chronic obstructive pulmonary disorder, or peripheral vascular disease)
* Any impaired sensation or weakness in either lower extremity
* History of serious concussion or head injury, defined as a loss of consciousness for \> 5 minutes and/or requiring medical treatment, or \> 2 concussions over the lifespan
* Any history of acute or chronic problems with balance, any dizziness, or \> 1 fall in the last 12 months
* Currently or regularly using any analgesic medications, over-the-counter remedies, or any other treatment for the purposes of pain relief (i.e., baby aspirin for heart health is allowed)
* Any current or chronic pain condition during the last year, located anywhere in the body with an intensity of \> 2/10
* Allergy to capsaicin or hot peppers
* Any skin lesion, breakage or irritation in the area targeted for the painful stimulus
* Significant skin sensitivity to soaps/creams/perfumes or to heat
* Poor circulation in the area targeted for the painful stimulus
* Prior participation in a split-belt locomotor learning study in the Neuromotor Behavior Lab in the past 2 years
