This research study is investigating whether people with Alzheimer's disease (AD) experience more changes to swallowing than their healthy age-matched peers. The prevalence of swallowing impairments in moderate-severe AD is high (85-93%), yet little is known about how swallow function evolves throughout the disease course in people with AD. The overall objective of this study is to evaluate swallowing function in adults with and without Alzheimer's disease. The investigator will also be involving the primary caregivers of individuals with Alzheimer's that are enrolled in the study to better understand the impact of swallowing impairments on the primary caregivers of those with Alzheimer's Disease.

Healthy adults and individuals with Alzheimer's disease will:

• undergo tests of cough and swallow function
• undergo tests of grip and tongue strength
• complete questionnaires

Caregivers of individuals with Alzheimer's disease will also complete questionnaires.

This study will involve one in-person research visit that will last approximately 1-1.5 hours and will consist of a screening, cough testing, swallow function testing, assessments of hand grip and tongue strength, and completion of questionnaires. Caregivers of those with Alzheimer's disease will also complete questionnaires.

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)

The overall objective of this proposal is to evaluate swallow function in 80 healthy adults and 80 individuals with AD and to evaluate caregiver perceptions of swallow function and burden in 80 caregivers of individuals with AD. Thus, this study will enroll healthy adults, individuals with AD, and caregivers of individuals with AD.