Vagus Nerve Stimulation on Improving Sleep in Inpatient Rehab for Post-Acute Stroke

The goal of this clinical trial is to learn if a device which provides vagal nerve stimulation, applied to the tragus of the ear via an ear clip, can improve sleep in individuals recovering from stroke while they are treated in a rehabilitation hospital. The main questions this study aims to answer are: 1. Does using this device improve insomnia? 2. Does this device have any impact on the person's stroke severity, mobility, self-care, or ability to think? Researchers will compare this treatment to a sham (a look-alike device that will not deliver the stimulation). Participants will: * Complete questionnaires about insomnia and their ability to think * Use the device for 30 minutes every evening for at least 10 nights during their inpatient stay * Complete a log tracking their use of the device and any concerns

Inclusion Criteria: 1. Admitted to Casa Colina's acute rehabilitation service 2. Diagnosis of ischemic stroke 3. Age 18 years or older 4. English or Spanish speaking 5. Sufficient cognition to follow program instructions tested Mini Mental Exam (score \>17/30) 6. Confirmed sleep abnormalities based on the Insomnia Severity Index (ISI) meeting criteria for subthreshold or clinical insomnia (score \>7/28) Exclusion Criteria: 1. Hemorrhagic stroke or hemorrhagic conversion of ischemic stroke 2. Other confirmed neurological diagnoses 3. Previous surgical intervention on the vagus nerve 4. Any open wound or cancerous lesions at the ear within 1 inch of the ear tragus 5. Contraindication to the device, including patients with severe bradycardia, patients with a permanent implanted metallic or electronic device or jewelry at close proximity (2cm) to the ear tragus, patients with a recent (within 1 year) history of trigeminal neuralgia, pregnancy