Inclusion criteria for AD cohort:

1. adult ≥60 years old
2. diagnosis of AD by a neurologist (confirmed with imaging, spinal tap, behavioral testing)
3. no prior history of other neurological diseases (aside from stroke which has resolved with no current symptoms)
4. no prior history of respiratory diseases
5. no prior history of head and neck surgery/head and neck cancer/radiation to head and neck region
6. consuming some form of oral intake
7. able to follow basic directions
8. able/willing to provide consent/assent.

Exclusion Criteria for AD Cohort:

1. individual <60 years old
2. Diagnosis of another type of dementia
3. History of neurological/respiratory diseases
4. History of head and neck surgery/head and neck cancer/radiation to head and neck region
5. not consuming any oral intake
6. Unable to follow basic directions
7. Unable to provide consent based on the University of California, San Diego Brief Assessment of Capacity to Consent (UBACC), score <15 OR provide assent and a legal guardian/health care decision maker provides consent.

Inclusion criteria for care partners of individuals with AD will be:

1. care partner of an individual with AD
2. willing to complete questionnaires/participate in an interview.

Exclusion Criteria for Caregivers of Individuals with AD:

1. not the primary caregiver of an individual with AD
2. unwilling to complete questionnaires/semi-structured interview

Inclusion criteria for community-dwelling adults will be:

1. adult ≥60 years old
2. no prior history of neurological diseases (aside from stroke which has resolved with no current symptoms)
3. no prior history of respiratory diseases

3) no prior history of head and neck surgery/head and neck cancer/radiation to head and neck region 4) no prior history of swallowing difficulties based on participant report. 5) Score ≥25th percentile based on sex/age/education/race on the Montreal Cognitive Assessment (MOCA)

Exclusion Criteria for Healthy Cohort:

1. individual <60 years old
2. history of neurological disease
3. history of respiratory disease
4. history of head and neck surgery/head and neck cancer/radiation to head and neck region
5. history of swallowing difficulties
6. Score <25th percentile based on sex/age/education/race on the Montreal Cognitive Assessment (MOCA)

History of severe allergic reactions to study medication Currently pregnant or breastfeeding Recent participation in another clinical trial within the last 30 days Presence of uncontrolled medical conditions that could affect safety