Beta-Blocker Influences on Inflammatory and Neural Responses to Stress

Inclusion Criteria:

* Ages 18-30 years
* Right-handed
* Fluent in English reading, writing, and speaking at least at a 10th grade level
* Body mass index (BMI) less than or equal to 35 kg/m\^2

Exclusion Criteria:

Assessed as screening, reassessed at Session I:

* Non-removeable metal devices/implants/objects in the body
* Severe claustrophobia (assessed by self-report)
* Currently pregnant
* Left-handed
* Body mass index (BMI) greater than 35 kg/m\^2
* History of fainting spells or any heart condition
* History of or present low resting heart rate (\< 60 BPM) and/or low blood pressure (systolic blood pressure \< 80mmHg)
* Self-reported physical illnesses: diabetes, cardiovascular diseases, high blood pressure, inflammatory bowel diseases, rheumatoid arthritis, asthma, autoimmune disease, Crohn's disease, ulcerative colitis, lupus
* Any self-reported diagnosed mental illness
* Current use of prescription medications (except hormonal contraceptives)
* Current or recent regular nicotine/tobacco use (cigarettes, e-cigarettes, vape, chewing tobacco, nicotine gum)
* Current regular (daily or almost daily) recreational drug use = 4 or more times per week

Instructed against during Session I, reassessed at Session II:

* Received any vaccine within the past two weeks
* Severe sleep disturbance (3-4 hours of sleep loss) the night before Session II
* Vigorous physical activity on the day of Session II
* Acute illness or allergy symptoms on the day of Session II
* Usage of over-the-counter medications on the day of Session II
* Usage of recreational drugs within 48 hours of Session II
* Usage of alcohol on the day of Session II